INVESTIGATION OF THE ASSASSINATION OF PRESIDENT JOHN F. KENNEDY APPENDIX TO HEARINGS BEFORE THE SELECT COMMITTEE ON ASSASSINATIONS OF THE U.S HOUSE OF REPRESENTATIVES NINETY-FIFTH CONGRESS SECOND SESSION VOLUME VIII ACOUSTICS, POLYGRAPH, HANDWRITING, AND FINGERPRINT REPORTS MARCH 1979 Printed for the use of the Select Committee on Assassinations U.S. GOVERNMENT PRINTING OFFICE 46-129 0 WASHINGTON: 1979 For sale by the Superintendent of Documents, U.S. Government Printing Office Washington. D.C. 20402 Stock No.. 052-070-04979-1 SELECT COMMITTEE ON ASSASSINATIONS LOUIS STOKES, Ohio, Chairman RICHARDSON PREYER, North Carolina SAMUEL L. DEVINE, Ohio WALTER E. FAUNTROY, STEWART B. MCKINNEY, Connecticut District of Columbia CHARLES THONE, Nebraska YVONNE BRATHWAITE BURKE, HAROLD S. SAWYER, Michigan California CHRISTOPHER J. DODD, Connecticut HAROLD E. FORD, Tennessee FLOYD J. FITHIAN, Indiana ROBERT W. EDGAR, Pennsylvania Subcommittee on the Subcommittee on the Assassination of Assassination of Martin Luther King, Jr. John F. Kennedy WALTER E. FAUNTROY, Chairman RICHARDSON PREYER, Chairman HAROLD E. FORD YVONNE BRATHWAITE BURKE FLOYD J. FITHIAN CHRISTOPHER J. DODD ROBERT W. EDGAR CHARLES THONE STEWART B. MCKINNEY HAROLD S. SAWYER LOUIS STOKES, ex officio LOUIS STOKES, ex officio SAMUEL L. DEVINE, ex officio SAMUEL L. DEVINE, ex officio STAFF G. ROBERT BLAKEY, Chief Counsel and staff Director GARY T. CORNWELL, Deputy Chief Counsel (II) (II) CONTENTS Page A Study of the Acoustics Evidence Related to the Assassination of President John F. Kennedy........................1 The Analysis of Yuri Nosenko's Polygraph Examination..............187 The Analysis of Jack Ruby's Polygraph Examination ...............197 The Examination of the Handwriting and Fingerprint Evidence ......... 223 Exhibits ............................................................ 251 (III) A STUDY OF THE ACOUSTICS EVIDENCE RELATED TO THE ASSASSINATION OF PRESIDENT JOHN F. KENNEDY Report to the Select Committee on Assassinations U.S. House of Representatives Ninety-fifth Congress Second Session March 1979 (1) CONTENTS Page An analysis of recorded sounds relating to the assassination of President John F. Kennedy by Mark R. Page Weiss and Ernest Aschkenasy........3 Analysis of recorded sounds relating to the assassination of President John F Kennedy by Bolt Beranek and Newman Inc.....................33 Analysis of earwitness reports relating to the assassination of President John F Kennedy by Bolt Beranek and Newman Inc....................128 Addendum A; Report on the temperature in Dallas, Tex. November 22, 1963 ................................................................171 Addendum B; Report on wind conditions in Dallas. Tex., November 22, 1963 .................................................................175 Addendum C; Memorandum from G. Robert Blakey to the Select Committee on Assassinations on the Mannlicher-Carcano firing test.............183 (2) (2) 3 AN ANALYSIS OF RECORDED SOUNDS RELATING TO THE ASSASSINATION OF PRESIDENT JOHN F. KENNEDY* (Prepared for Select Committee on Assassinations, U.S. House of Representatives, by Mark R. Weiss and Ernest Aschkenasy, Depart- ment of Computer Science, Queens College, City University of New York, February 1979) Page Acknowledgment ..................................................... 4 Foreword ........................................................... 4 Section 1.0 Introduction and summary............................... 5 1. 1 Background ................................. 5 1. 2 Materials provided for the examination ..... 5 1. 3 Characteristics and sources of the recorded sounds....................................... 6 1. 4 Basic principles and methods of analysis .... 6 1. 5 Results of the analysis ................... 10 1. 6 Findings .................................. 10 1. 7 Outline of the report ..................... 11 Section 2.0 Description of the recorded sounds .................. 11 Section 3.0 The nature of the problem and the method of solution.. 11 3. 1 Distortion of the relative intensities of the echoes ..................................... 11 3. 2 Waveforms of the sounds on the DPD recording 12 3. 3 Possible sources of the impulse sounds ..... 15 3. 4 Method of the analysis ..................... 15 Section 4.0 Implementation of the analysis ....................... 16 4. 1 Preliminary considerations ................. 16 4. 1. 1 Source of the gunshot sounds ............... 16 4. 1. 2 Placement of the gun on the grassy knoll ... 16 4. 1. 3 Placement of the microphone on Elm Street .. 16 4. 1. 4 Selection of the coincidence window ........ 18 4. 1. 5 Prediction of echo sequences ............... 18 4. 2 Information needed to predict echo-delay sequences................................... 19 4. 2. 1 Identification of echo-producing objects.... 19 4. 2. 2 Measurement of distances in Dealey Plaza ... 19 4. 2. 3 The speed of sound.......................... 21 4. 3 Accuracy of the echo prediction procedure .. 21 Section 5.0 Comparison of the sequence of impulses in the DPD recording with sequences of predicted echoes .................. 26 5. 1 Prediction of echoes for November 22, 1963.. 26 5. 2 Correction of time delay measurements....... 26 5. 3 Comparison of the impulse and echo sequences 27 5. 4 Factors affecting the selection of impulses and echoes for correlation .................... 30 5. 4. 1 Relative strengths of echoes near the microphone location .................................. 30 5. 4. 2 Effects of the DPD radio dispatching system on the relative strengths of recorded echoes... 30 5. 5 Correlation of impulse and echo sequences... 31 5. 6 The probability that the recorded impulses are not gunshot sounds ......................... 32 -------------------- *Materials submitted for this report by the committee's acoustics panel were compiled by HSCA staff member Gary T. Cornwell. (3) 4 LIST OF FIGURES Figure: Page 1 Waveforms of the sounds of a gunshot ..................... 8 2 Waveforms of sounds in the DPD recording ................. 13 3 Expanded graph of waveforms of sounds in the DPD recording ................................................ 14 4 Microphone locations at Dealey Plaza ..................... 17 5 Paths of muzzle blast echoes ............................. 20 6 Waveforms of gunshot sounds received at microphone 4 of array 3 .................................................. 25 7 Identified impulses on the DPD recording ................. 28 8 Locations of the gun and path of the microphone computed for November 22, 1963......................................... 29 LIST OF TABLES Table l.--List of structures in Dealey Plaza that would have produced echoes of sufficient strength to have been recorded on the DPD tape ..................... 23 Table 2.--List of echo paths used in predictions of echo-delay times ..................... 23 Table 3.--Measured and predicted delay times of echoes for a gunshot fired on August 20, 1978.......................................... 24 Table 4.--Measured delay times of impulses and predicted delay times of gunshot echoes for November 22, 1963.............................. 27 ACKNOWLEDGEMENT The authors gratefully acknowledge the support and cooperation of the New York Police Department in providing both the facilities and personnel needed to make test recordings of gunshot sounds. We particularly appreciate the assistance of Sgt. Eugene McDonnell, Officer Mario Buda, and Officer Steve Baymack of the NYPD communications division, and Lt. Frank McGee and Sgt. John O'Brien of the firearms unit. We wish also to express our appreciation for the generous assistance of Dr. Ali Ghozati of the Queens College Department of Computer Science during the preparation of this report. FOREWORD On September 11, 1978, Dr. James Barger of Bolt Beranek and Newman, Inc. (BBN) presented to the House Select Committee on Assassinations the results of a BBN analysis of a Dallas Police Department (DPD) recording that had been made on November 22 1963. One of the reported findings was that, with a probability of 50 percent, the recording contains sounds of a gunshot, or at ]east sounds as loud as a gunshot, fired from the so-called grassy knoll area of Dealey Plaza in Dallas; they were received by a microphone on a DPD motorcycle that was moving on Elm Street at a speed of about 11 mph in the same direction as the Presidential motorcade. On October 24, 1978, the committee authorized the authors of this report to conduct an independent examination of that portion of the recording to determine with more certainty whether the sounds in question were of such a shot. The analysis was completed by the middle of December 1978 and described in a public presentation to the committee on December 29, 1978. This report describes the method and results of that analysis. 5 1.0 INTRODUCTION AND SUMMARY 1.1 Background On November 22, 1963, in Dallas, Tex. at the time that shots were being fired in the assassination of President John F. Kennedy, a radio on a Dallas Police Department (DPD) motorcycle that apparently had stuck microphone was transmitting sounds over channel 1 of the DPD radio network that were being recorded at DPD headquarters. In an analysis of this recording, authorized by the House Select Committee on Assassinations, Dr. James Barger and his colleagues at Bolt Beranek and Newman, Inc. (BBN) isolated four groups of sound impulses and identified them as probable sounds of gunshots, and not merely random noise. They calculated that the statistical probabilities that these identifications were correct were, in order of increasing time occurrence of the sounds, 88 percent, 88 percent, 50 percent, and 75 percent. BBN found that the probable cause of the first, second, and fourth of these groups of impulses were noises as loud as gunshots originating in the vicinity of the sixth floor southeast corner window of the Texas School Book Depository (TSBD) in Dealey Plaza. The probable cause of the third group of impulses was a similarly loud sound from the vicinity of the so-called grassy knoll area of Dealey Plaza. BBN also found that all of the groups of sounds were picked up by the microphone on a DPD motorcycle and that at the time of the third probable gunshot, the motorcycle was on Elm Street in Dealey Plaza, moving at a speed of about 11 miles per hour in the same direction as the motorcade. On October 24, 1978, the committee authorized authors of this report to perform an independent examination of sounds on the DPD recording to determine with a higher level of certainty if the third group of impulses was caused by the sounds of a gunshot from the grassy knoll. 1.2 Materials Provided for the examination: At the time we began our analyses, we were provided with the following materials: 1. A high-fidelity tape-recorded copy of the original DPD recording. 2. A high-fidelity tape-recorded copy of the DPD tape recording that had been examined by BBN. 3. A high-fidelity tape-recorded copy of the sounds of gunshots that were recorded by BBN during an acoustical reconstruction experiment conducted in Dealey Plaza on August 20, 1978. 4. A topographical survey map of Dealey Plaza, plotted at a scale of 1 inch equal to 10 feet. 5. A map of Dealey Plaza, plotted at a scale of 1 inch equal to 40 feet, on which the locations of microphones used in the reconstruction experiment were indicated. 6. Aerial and ground level photographs of Dealey Plaza and relevant surrounding structures. In addition, the committee staff provided to us various necessary items of informations, such as the heights of buildings in Dealey Plaza, the distance to objects not shown on the maps, the location of the DPD shooter during the BBN reconstruction experiment and the air temperature in Dealey Plaza at the time of the assassination and during the reconstruction experiment. 6 1.3 Preliminary review of the characteristics and sources of the recorded sounds During 1963, communications that were transmitted on channel 1 of the DPD radio dispatching system were recorded continuously on a Dictabelt recorder. On November 22, 1963, a microphone on a mobile transmitter that was set to channel 1 apparently became stuck in the position at about 12:28 p.m. and for about 5 minutes continuously transmitted sounds that it picked up. When we first listened to this interval on the DPD recording, we found that it contained a nearly continuous noise, with occasional speech, whistles, and clicks. Also recorded on the Dictabelt in this interval were the sounds that BBN identified as probable gunshots. To the ear, these sounds resembled static much more than they did a gunshot. However, as Dr. Barger testified in September, and as we independently verified, the equipment that was used in the DPD radio dispatching system was not designed to handle sounds as intense as a gunshot, and it was therefore likely to have recorded such sounds with very poor fidelity. Consequently, we recognized that these static-like sounds could be distorted gunshot sounds. On the other hand, such static-like sounds, theoretically could have been generated by a number of other sources, some acoustic, some related to electrical or mechanical disturbances in the DPD radio transmission, reception or recording equipment. Some test more discerning than the human ear was required to determine the probable cause of the sound impulses. 1.4 Basic principles and methods of analysis To answer the basic question, "Was the third group of recorded sounds generated by a gunshot from the grassy knoll? With a high level of certainty, these sounds needed to be examined for some characteristic that they would have had if they had been generated by such a gunshot, and would not be likely to have had if they had not been. Of the several characteristics that can be used, the most effective and most reliable one is the sequence of delay times of the muzzle-blast echoes. The firing of a gun generates a very loud, very brief explosive blast at the muzzle of the gun. This sound, which typically lasts about five one-thousandths of a second (0.005. seconds, or 5 milliseconds), spreads out in all directions from the gun. If the muzzle blast strikes 7 a wall of a structure, it will be reflected from the surface and will move away from it in a new direction. If the muzzle blast strikes the corner of a structure, it will be diffracted, that is, it will spread out from the corner in many directions. These reflected and diffracted sounds are the echoes of the muzzle blast. Like the muzzle blast, which they closely resemble, the individual echoes are very short in duration. The strengths of the echoes tend to diminish with time, the earliest ones, being very loud and the later ones growing progressively weaker as they arrive from increasingly distant locations. The time taken for the muzzle blast to be heard at some location depends solely on how fast the sound travels and how far the listener is from the gun. For example, at 65 deg F. the speed of sound is 1123 ft/sec. A listener 112.3 feet away from a gun would hear its muzzle blast 0.1 second after the gun was fired. The time taken for the muzzle blast echoes to be heard also depends on the speed of sound and on the total distance each echo must travel, which is the total of the distance from the gun to the echo-producing object and then to the listener. Since the distance traveled by the muzzle blast to a listener must be less than the distance traveled by one of its echoes, the bang of the muzzle blast is always heard first. Then the echoes that are produced by the muzzle blast bouncing off the corners and surfaces of structures are heard. If we now assume that the sound source (the gun) and the listener are located in a typical urban environment, with a number of randomly spaced echo-producing structures, it is possible to see that the pattern of sounds a listener will hear will be complex and unique for any given pair of gun and listener locations. For example, assuming a fixed location of a listener, the echoes that he hears and the times at which he hears them will be related uniquely to the location of the gun, since for each different location of the gun, even though the distances from the listener to the various echo-producing objects are the same the distances from these objects to each gun location are different. Consequently, the times at which the echoes are heard will be different for each location of the gun. Similarly, assuming a fixed location of the gun, any change in the location of the listener will change the distances between him and the echo-producing structures, and thus the timing of the pattern of sounds he hears. If the listener is in motion as the muzzle blast and the various echo sounds reach him, the times at which he hears the muzzle blast and its echoes will be related uniquely to his location when he hears each sound. A listener cannot tell, from the sounds of a gunshot, when the gun was fired. He can determine only the times that elapse between the muzzle blast and each of its echoes. These elapsed times are called the echo-delay times. Because the echo travel times are uniquely related to the locations of the gun and the listener, the echo-delay times are unique to any given pair of those locations. Hence, if we know the temperature (and thus, the speed of sound) and the location of the echoproducing structures, echo-delay times can be used to characterize the sounds of a gunshot for any pair of shooter and listener locations. The "listener" that we have discussed, of course, could be either a human ear or a microphone. If a microphone receives the sounds and they are subsequently recorded, the recording becomes a picture of the event, not unlike a "fingerprint," that permanently characterizes the original gun and microphone locations. Echo-delay times in such recordings can be measured easily and precisely by producing a graph of their waveforms on an oscillogram, or oscillograph. Such a graph is shown in figure 1. The narrow peaks represent individual sounds of brief duration (that is, impulse-sounds). The heights of the peaks correspond to the loudness of the impulsesounds; the spacing between peaks corresponds to the time that elapses between them. The largest of the impulse peaks is the muzzle blast. The peaks that follow it are its individual echoes. The distance between the peak that is identified as the muzzle blast and each peak that repre- 8 sents an echo is a measure of the delay time of the echo. To convert this distance to a time measurement, it is multiplied by the time-scale of the graph. For example, the muzzle blast impulse in figure 1 and the sixth peak identified as an echo are 47 millimeters apart. Since the time-scale is 1 millisecond per millimeter (1 msec/mm), the measured echo-delay time is 47 milliseconds. FIGURE 1 WAVEFORMS OF THE SOUNDS OF A GUNSHOT 9 It is easy to see how such a graph may be used for identification purposes. It provides a picture of the complex, random spacings of the echo-delay times. When the temperature of the air and the locations of the echo-producing objects are known, the graph is uniquely related to a particular pair of gun and microphone locations. This complex picture can be compared to other such graphs. If the random pattern of echo-delay times (the spacings between peaks) matches in any two such graphs, it may be concluded that the sounds and listener locations that produced both graphs were the same. Of course, it may be that no second graph can be found that matches the first. Using the fingerprint identification process as an analogy, if a latent fingerprint taken from a knife found protruding from a murder victim's body is given to the FBI for identification, it may be that no matching "known" print is on file at FBI headquarters and that the murderer cannot be immediately identified. Furthermore, the police may proceed to take fingerprint samples from all of the suspects in the case and find that none match the one found on the murder weapon. In the end, the latent fingerprint may not be identified. Applying the analogy to the graphs of sounds, our problem was to see if any of a number of assumed pairs of shooter and microphone locations would produce a pattern of sounds whose graph would match the graph of the sounds in question on the DPD tape. Before beginning the search, we knew that, just as in fingerprint identification cases, in the end we might find no match. If that occurred, of course, either of two conclusions would be required: (1) The real shooter and microphone locations could not be identified, or (2) the sounds on the tape were not produced by a gunshot in Dealey Plaza. On the other hand, if we found a shooter and microphone location that in combination would cause the same unique, random pattern of echo-delay times that were contained on the DPD tape recording, those sounds could be identified as probably being caused by such a gunshot. For the sounds on the DPD recording, we knew what two of the four conditions that determine echo-delay time were at the time of the assassination. We knew what the speed of sound was and we knew where the major echo-producing objects were (and still are). We did not know exactly where to locate the gun, nor did we know through which sequence of locations on Elm Street to move the microphone. Therefore, we had to determine numerous hypothetical sequences of echo-delay times for gunshots that may have been fired from a variety of locations on the grassy knoll and picked up by microphones that moved through a variety of locations on Elm Street. This was accomplished in the only practical way possible--by predicting (i.e., mathematically calculating) the echo-delay time sequences that would be obtained for the various locations of a gun and a microphone. After numerous comparisons between the echo-delay times for the sounds on the DPD recording and various predicted patterns for assumed motorcycle and shooter locations that did not match, a combination of motorcycle and shooter locations was found which mathematically produced a predicted pattern that showed strong similarities to the pattern of impulses on the DPD tape. However, to determine with a high level of certainty if these two sequences of echodelay times, which were derived from different data, represented the same source, it was not enough to show that the sequences looked alike. 10 They had to be shown to be alike in an objective sense, that is, by use of a method of comparison that disregarded potentially misleading appearances. Such a method was provided by a computation of the binary correlation coefficient of the two sequences. The binary correlation coefficient of two sequences is a number that is exactly 1.0 if the sequences are identical and that rapidly approaches zero as they grow more dissimilar. As used in this analysis, the binary correlation coefficient takes into account the number of echo-delay times in each of the sequences and the number of echoes that coincide. Echoes in the two sequences are said to coincide if their delay times differ by a small amount. The smaller this amount, or "coincidence window," can be made while maintaining a high binary correlation coefficient, the greater will be the probability that the DPD sequence represents a gunshot from the grassy knoll. 1.5 Results of the analysis Two different comparisons were made between the sequence of echodelay times on the DPD tape and the most similar sequence of predicted echo-delay times. One of the comparisons was between those recorded sounds that were significantly louder than the average background noise and those predicted echoes that would have been recorded with comparable loudness. In the other comparison, the delay times of all of the recorded sounds and of all of the predicted echoes, up to a total delay of 50 milliseconds from the muzzle blast, were compared. The computed binary correlation coefficient was found to be 0.79 for the first comparison and 0.75 for the second. In both of the comparisons described chore, the coincidence window was set at -+1 millisecond. That is, a menanted echo-delay time and a predicted one were said to coincide only if they were no more than 1 millisecond apart. For sequences that correlated at levels greater than 0.7 with a coincidence window of a millisecond. the statistical probability was 95 percent or more that the sequences represented the same source--a sound as loud as a gunshot from the grassy knoll. Put alternative]y, the probability that the sounds on the DPD recording were generated by sources other than a sound as loud as a gunshot originating from the grassy knoll is 5 percent or less. 1.6 Findings The results of our analysis of sounds on the DPD recording permit the following findings: 1. The recording very probably contains the sound of a gunshot that was fired from the grassy knoll. The probability of this event is computed to be at least 95 percent. 2. The microphone that picked up the sounds of the probable gunshot was on Elm Street and was moving at a speed of about 11 miles Der hour in the same direction as the motorcade. At the time the probable gunshot was fired, the microphone was at a point about 97 feet south of the TSBD and about 27 feet east of the southwest corner of the building. (For both distances, the uncertainty is about +- 1 foot.) 3. The probable gunshot was fired from a point along the east-west line of the wooden stockade fence on the grassy knoll, about 8 feet (-+-5 feet) west of the corner of the fence. 11 1.7 Outline of the Report The method and results of this analysis are described in detail in the sections of the report that follow. The sounds on the DPD recording are described in section 2. Following in section 3, is a discussion of the nature of the problems in this analysis and of the considerations that underlie the method of solution. Section 4 discusses the steps that were taken to implement the procedure for predicting echo-delay times and describes the method and results of a test of this procedure. Section 5 discusses the methods that were used to determine and to compare echo-delay times for the recorded and predicted sequences. 2.0 DESCRIPTION OF THE RECORDED SOUNDS The DPD recording contains a wide range of sounds--speech, clicks, whistles, motor noises, sirens and even the sound of a carillon bell. Mostly, the recording contains sounds generated during normal communications on channel 1 of the DPD radio dispatching system. The speech transmissions usually were preceded and followed by sharp clicks. These were keying transients, probably generated by the switch on the transmitter microphones when they were turned on or off. Occasionally, a transmission was attempted while another one was in progress. When this occurred, the interference between the two transmitters usually generated a brief whistle, known as a heterodyne tone, that immediately followed the keying click of the oncoming microphone. At a time that the BBN analysis estimates to have been about 12:28 p.m., a microphone on a mobile unit apparently became stuck in the "on" position and began to transmit a continuous noise that is believed to be the sound of a motorcycle engine. For the first 2 minutes of the stuck-microphone transmission, the sound level of this noise is fairly constant. Occasionally, clicks and whistles can be heard through the noise, indicating attempts by other transmitters to use the channel. At several points, voices can be heard, but, being obscured by the noise, they cannot be understood. At 133 seconds after the start of the stuck-microphone transmission, the level of the noise drops by about 6 decibels (that is, to about one-fourth of its previous level). At almost the same moment a voice can be heard, communicating a brief but unintelligible message. This is followed about 3 seconds later series of randomly spaced, loud clicks and pops that lasts for at least 10 seconds. Some of the clicks occur singly, some in groups. Only one of them is accompanied by a heterodyne whistle and by an audible but unintelligible voice. 3.0 THE NATURE OF THE PROBLEM AND THE METHOD OF SOLUTION 3.1 Distortion of the relative intensities of the echoes The sounds on the DPD recording that are thought to be those of gunshots begin about 5 seconds after the decrease in the level of the continuous noise and last for about 8 seconds. To the ear, these sounds resemble static, not gunshots. However, the equipment that was used in the DPD radio dispatching system in 1963 would have distorted the sounds of gunfire. The effect would have been to compress the peak amplitude of the sounds of the muzzle blast and of its strongest echoes, making them only slightly louder than those of some of the weaker 12 echoes. Furthermore, if the microphone was on a DPD motorcycle in the motorcade, most of the many very weak echoes of the muzzle blast would have been obscured by the noise of the motorcycle engine (which is possibly the source of the continuous noise on the DPD recording). Consequently, the sounds of a gunshot would have been recorded as a sequence of very brief impulse-sounds (the muzzle blast and its loudest echoes), only a few of which would have been larger than the accompanying engine noise, and none of which would have sounded to the ear like gunshots after being distorted by the limiting circuitry of the DPD radio and recording equipment. 3.2 Waveforms of the sounds on the DPD recording The waveforms of sounds in the DPD recording are shown in figure 2. The waveforms in the bracketed region include the group of impulse-sounds that the BBN analysis identified as a probable, gunshot from the grassy knoll. This segment of the recording begins 144.9 seconds after the start of the stuck-microphone transmission and lasts for 0.36 seconds. The noise thresholds shown in the figure indicate the average peak levels of noise (mostly motorcycle noise) that can be heard immediately before and after this segment. 13 FIGURE 2 WAVEFORMS OF SOUNDS IN THE DPD RECORDING 14 Figure 3 shows the bracketed region in greater detail. The narrow peaks that exceed the thresholds, as well as many of those that do not, are the waveforms of the impulse-sounds that may be the sounds of a gunshot. Impulse peaks that are less that 1 millisecond apart are consid- ered to be part of the same impulse. Altogether, 15 impulses exceed the thresholds. Five of them occur in the first 85 milliseconds following the one that is labeled as the muzzle blase. The remaining tone impulses occur in the 100-millisecond wide interval that begins about 280 milli- seconds after the assumed muzzle blast. FIGURE 3 EXPANDED GRAPH OF WAVEFORMS OF SOUNDS IN THE DPD RECORDING 15 3.3 Possible sources of the impulse sounds While it was possible that the louder impulse noises were the distorted sounds of a gunshot, it also is possible that they could have been generated in other ways. For example, they could have been the sounds of misfiring of the motorcycle engine. They could have been static-like impulse noises generated by the motorcycle's ignition system and picked up by the transmitter. The microphone that was stuck in the "on" position could itself have been the cause of impulses if from time-to-time it became unstuck and turned off briefly and then immediately turned on again. Impulse noises in the recording could also have resulted from scratches in the dictabelt on which the recording was made. Other components of the communication system could have been malfunctioning, producing electrical or mechanical disturbances that would have been recorded as clicks. 3.4 Method of the analysis The essential questions to be answered were:"What is the source of the impulse-sounds in the DPD recording? Are they derived from the sounds of a gunshot that was fired from the grassy knoll and picked up by a microphone that was moving on Elm Street, or are they derived from one or more of the many other possible sources?." These questions could be answered with a high degree of certainty if the impulses could be shown to exhibit a characteristic that they would be expected to exhibit if they had been generated by a gunshot, and would not be likely to exhibit if they had not been. As explained in 1, such a characteristic is found in the unique pattern of time delays of echoes that buildings and other structures in Dealey Plaza would generate for a gunshot fired from the grassy knoll. If the impulse noises are the distorted sounds of a gunshot, their spacing should closely match that predicted for a shot fired from some location on the grassy knoll and "heard" by a microphone traveling along some path on Elm Street at 11 miles per hour. The closer the match between the actual and the predicted sequences, the greater the probability that the impulses are the sounds of a gunshot. If no shooter and microphone can be found that can produce a sequence of echoes that closely matches the sequence of impulses on the tape recording, then it would have to be concluded that the impulses were not generated by sounds received by a microphone moving on Elm Street from a gun fired on the grassy knoll. The procedure for determining the probable cause of the specified group of impulses on the DPD recording thus consisted of three steps. First was to calculate the pattern of echo delays that would be pro duced by a gunshot from a variety of locations on the grassy knoll and recorded by a microphone moving along a variety of paths on Elm Street. Then, select the sequence of predicted echoes that most closely matched the actual recorded sequence of impulses. Finally, compute the probability that impulse sounds generated by sources other than the predicted gunshot could occur by chance in a sequence that would match the selected echo sequence as closely as did the actual DPD recording. 16 4.0 IMPLEMENTATION OF THE ANALYSIS 4.1 Preliminary considerations The implementation of the three-step procedure of the analysis required the consideration of a number of questions. Each of these affected either the results of the analysis or the method by which the required echo-delay time sequences were obtained. 4.1.1 Source of the gunshot sounds If a gun was fired from the grassy knoll during the assassination, the would-be assassin reasonably could have used either a rifle or a pistol, since the target would have been less than 150 feet away. Since rifles typically fire bullets that travel faster than the speed of sound, the firing of it rifle generates two intermixed echo sequences composed of the echoes of the muzzle blast and the echoes of the continuously generated shock wave that is created by a bullet in supersonic flight. On the other hand, most pistol bullets do not fly at supersonic speeds. A pistol that fires a subsonic bullet generates only the set of echoes of the muzzle blast. Since we did not know what type of gun, if any, had actually been used on November 22, 1963, we sought only to compare the DPD tape with predicted sequences of echoes of muzzle blasts which would have been present regardless of the type of weapon fired.* 4.1.2 Placement of the gun on the grassy knoll The BBN analysis indicated that the gun was in the vicinity of the grassy knoll. During the acoustic reconstruction experiment that was conducted by BBN in Dealey Plaza on August 20, 1978, shots were fired from behind the wooden stockade fence on the grassy knoll. This location was consistent with available eyewitness and earwitness testimony. It was a reasonable one since it afforded good visibility of Elm Street while providing good cover for the shooter of a gun. At any other location on the grassy knoll either the visibility or the cover would have been substantially poorer. However, it is uncertain exactly where a shooter would have stood behind the fence, since equally good locations can be found up to 25 feet along the fence either north or west of its corner. 4.1.3 Placement of the microphone on Elm Street The BBN analysis placed the stuck microphone on Elm Street in the vicinity of the fourth microphone in the third array of microphones that were set up in Dealey Plaza during the acoustic reconstruction experiment. As illustrated in figure 4, the microphones were located in the center of the street at points 18 feet apart along the route of the Presidential motorcade, from the intersection of Houston and Main Streets to the location of the Presidential limousine on Elm Street in Zapruder frame 312. The sounds of a gunshot from the grassy knoll received by each of these microphones were recorded during the experiment. Later, BBN determined the degree of match between the ----------------------------------- *The DPD recording does contain a series of impulses that precede the large impulse ultimately determined to be the muzzle blast. The probability that these earlier impulses were the sounds of supersonic shock wave was discussed by Dr. Barger in his testimony before the committee on Dec. 29, 1978. See Vol. V of the hearings before the select committee, 94th Cong. 2d session (Washington, D.C.: U.S. Government Printing Office, 1979). 17 recordings from each of these microphones and the impulse noises on the DPD recording by calculating their binary correlation coefficients. A coincidence window of _+_ 6 milliseconds was used for these comparisons. Only one of the 36 comparisons yielded a correlation coefficient greater than 0.5 when compared with the segment of the DPD tape that is here at issue. That one--for the sounds received by microphone 4 in array 3--was at a level of 0.8, indicating a strong similarity between the echo sequence that was heard at that test loca- FIGURE 4 MICROPHONE LOCATIONS AT THE DEALEY PLAZA tion in Dealey Plaza and the impulse sequence on the DPD recording. The low values of the binary correlation coefficients that were calculated for all of the other microphones indicate that there is no other microphone location either on Elm Street or on Houston Street at which a sequence of echoes caused by a shot from the grassy knoll could 18 be heard that was even moderately similar to the sequence of impulses on the DPD recording. It was therefore clear that for the purpose of analysis the microphone location in Dealey Plaza for which echo sequences had to be obtained was in the vicinity of microphone 4 of array 3. This region extends along Elm Street from halfway between microphones 3 and 4 to halfway between microphones 4 and 5, and from curb to curb (since the presumed motorcycle with the stuck microphone could be anywhere to the right or left of the center of the street). 4.1.4 Selection of the coincidence window To compare sequences of impulses and echoes by use of the binary correlation coefficient, it was necessary first to determine how many echoes coincided with impulses. Ideally, if the microphones that were used in the acoustic reconstruction experiment could have been spaced very closely along the route of the motorcade, say, 1 foot apart, and spread from curb to curb, impulses and echoes that were within 1 millisecond of one another could have been considered coincident. For practical reasons, the microphones were located in the middle of the street and spaced 18 feet apart. Also, only one of many possible shooter locations was used. To take into account these practicalities, the coincidence window for BBN's analysis was made -+6 milliseconds. If a window of -+ 1 millisecond had been used, there would have been few points of coincidence in any comparison, and all of the calculated binary correlation coefficients would have been small, since the chances would have been small that a microphone and a shooter would (have) been arbitrarily located in precisely the correct positions to receive a sequence of echoes that. coincided with the sequence of impulses to within 1 millisecond. By increasing the coincidence window to +6 milliseconds, the number of coincident impulses and echoes was increased. However, so was the possibility that an impulse generated by a source other than a gunshot would appear to coincide with an echo. The major consequence of this was the value of 50 percent computed as the statistical probability that the impulses under examination were caused by the sounds of a gunshot. To increase the certainty in our findings above a 50-percent level, we had to be able to reduce the coincidence window to as low a value as possible, preferably to -+-1 millisecond or less. Theoretically, this could be accomplished by placing microphones l foot apart in the region of interest and conducting additional test firings in Dealey Plaza from various locations on the grassy knoll With respect to the microphone location problem along the relevant area on the street would be 720 square feet. Therefore, if, as in the BBN acoustic reconstruction experiment, microphones were placed in arrays of 12 each, a total of 60 arrays would be required for each position of a gun fired on the grassy knoll. Clearly, this approach was impractical. 4.1.5 Prediction of echo sequences The only practical way to obtain the needed echo sequence was to predict them analytically. Using fundamental principles of acoustics, it was possible to compute the time it would take for the sound of a muzzle blast to travel from a gun at any assumed point on the grassy knoll to a microphone at any assumed point on Elm Street. Knowing where the echo-producing objects were in Dealey Plaza, it was also 19 possible to compute the time it would take for echoes of the muzzle blast to travel from the gun to the microphone. Subtracting the muzzle-blast travel time from the echo travel times yielded the required sequence of echo-delay times. The principles of acoustics that underlie this approach are described in detail in BBN Report. No. 3497 that was submitted to the committee in January 1979.* The essential principles can be summarized as follows: 1. Most sounds spread out in all directions from the source of the sound. 2. If the medium (in this case, air) through which sound travels is uniform, sound will travel in straight lines from the source and the same constant velocity in all directions of travel. 3. The time taken for sound to travel from one point to another can be computed by dividing the distance between the points by the speed of sound. For example, at a speed of 1,100 feet per second, it will take 0.5 second for sound to travel a distance of 550 feet. Conversely, the distance traveled by a sound can be computed by multiplying the travel time by the speed of sound. 4. Sound traveling through air will reflect from the surfaces and diffract from the corners of structures such as buildings, walls and columns. 4.2 Information needed to predict echo-delay sequences Before the echo travel times could be calculated, it was necessary to determine three things: (1) Which objects in Dealey Plaza would produce echoes in the region of interest, on Elm Street for a gun fired from the vicinity of the grassy knoll; (2) how far these objects were from the locations of the gun and of the microphone; and (3) what was the speed of sound under the conditions for which the echo travel times were to be predicted. When the required information had been obtained, it was used first to determine the accuracy of the echo procedure. Then it was used to predict echoes for comparison with the impulses in the DPD recording. 4.2.1 Identification of echo-producing objects The objects in Dealey Plaza that would generate relevant echoes were identified with the aid of a topographical survey map of the plaza that was drawn to a scale of 1 inch equal to 10 feet. Most of these objects were corners of buildings or of walls that, as illustrated in figure 5, produced muzzle blast echoes in the selected region on Elm Street by diffracting the incident sound of a muzzle blast that was generated in the vicinity of the grassy knoll. Two of the objects, the wall of the DCRB and the curved wall at the reflecting pool, produced echoes by reflecting such a sound. In all, we were able to identify 22 objects that would generate echoes of sufficient strength that, they would have been recorded on the Dictabelt recording. (See table 1.) 4.2.2 Measurement of distances in Dealey Plaza The distances of the echo-producing objects from positions of a gun and a microphone were determined by direct measurement on the -------------------------------------- *This report follows the present report. 20 survey map. By comparing the known widths of buildings in Dealey Plaza with measurements made on the map, we found the distances measured on the map to be accurate to about 0.5 foot. We measured distances on the map in millimeters, to the nearest half-millimeter. This simplified the making of measurements by providing a decimal FIGURE 5 PATHS OF THREE MUZZLE BLAST ECHOES scale. To simplify the calculation of the travel time of the echoes, we converted the speed of sound to an equivalent value for map distances that were measured in millimeters. For example, a speed of sound of 1,123 feet per second was converted to 2,852 millimeters per second for map measurements made in millimeters. 21 4.2.3 The speed of sound The speed of sound in air is primarily a function of the temperature of the air. At a temperature of 65(deg) Fahrenheit, it is 1,123 feet per second, and at 90(deg) Fahrenheit it is 1,150 feet per second. To a first order approximation, in this temperature range the speed of sound increases at a rate of 1 foot per second per degree Fahrenheit. By comparison, humidity has a negligible effect on the speed of sound in air. Similarly, small variations in the temperature at different locations in Dealey Plaza would have a negligible effect on the average speed of sound over the path lengths of the echoes. According to records of the weather bureau in Dallas, as obtained by the committee staff,* the temperature in Dallas at 12:30 p.m. on November 22, 1963 was 65(deg) Fahrenheit. This was substantially confirmed by a photograph that was taken in Dealey Plaza at about that time. In it, a sign on top of the TSBD can be seen on which the time is indicated as 12:40 and the temperature in Dealey Plaza as 68 (degree) Fahrenheit. Even if the temperature that was supplied by the weather bureau varied from the temperature in Dealey Plaza by 3 (degree) Fahrenheit, the resulting error of 3 feet per second is less than 0.27 percent of the speed of sound at 65 (degree) Fahrenheit. For most of the echoes, the resulting error in the computed echo-delay time would be less than 0.25 millisecond. Even for the echoes that travel the longest echo paths, the error would be less than 1 millisecond. In either case, the error is within the accuracy required for the echo prediction procedure. As is explained later in this report, temperature differences up to 10 (deg) Fahrenheit would have had negligible effect on the final results and would not substantially have changed the final conclusion nor the degree of confidence (the final statistical probability) that can be appropriately assigned to it. Wind also will affect the speed of sound, increasing or decreasing it by an amount that depends on the speed of the wind and on the angle between the direction of the wind and the direction the sound travels. However, the delay time of an echo, which is determined by subtracting the muzzle blast travel time from the echo travel time, will be affected by wind only to the extent that the wind affects the echo and muzzle blast travel times differently. This in turn depends on the difference between the direction of the echo path and the direction of the direct muzzle blast path. For a gunshot fired from the grassy knoll and heard on Elm Street, the travel of most echoes is in approximately the same direction as the directly received muzzle blast. Consequently, the effect of wind on the delay times of these echoes is comparatively small, becoming significant only for windspeeds greater than 40 miles per hour. The weather bureau recorded winds in Dallas on November 1963, as ranging only between 13 knots and 17 knots, which is roughly equal to 15 to 20 miles per hour.** 4.3 Accuracy of the echo prediction procedure Before proceeding to predict sequences of echoes for comparison with the sequence of impulses on the DPD recording, the accuracy of --------------------------------------- * See addendum A to the acoustics reports. ** The actual recordings made at Dallas Love Field were 13 knots at 11:55 a.m., 13 knots at 12:30 p.m., and 17 knots at 1:00 p.m. See addendum B to the acoustics report. 22 the echo prediction procedure was tested. Given the estimated accuracy of the map, we expected to be able to predict echo-delay times to within - + 1 millisecond for specified locations of a gun and a microphone. However, it was essential to verify that this accuracy would be achieved in practice and that the identified echo-producing objects would generate significant echoes in the region of interest on Elm Street. To test the procedure, we predicted the delay times of the echoes that would be received by a microphone at the location of microphone 4 of array 3, as shown in figure 5, for a shot fired from the grassy knoll by the DPD shooter during the acoustic reconstruction experiment. We then compared the predicted echo-delay times to echo-delay times actually recorded on the BBN tape recording of the shot that was fired by the DPD shooter. At the time that the test shot was fired, the temperature in Dealey Plaza was approximately 90(deg) Fahrenheit. Accordingly, the value used for the speed of sound was 1,150 feet per second. As discussed in section 4.1.5, the echo-delay time is computed by subtracting the muzzle blast travel time (185.2 msec.) from the echo travel time. The muzzle blast travel time is obtained by dividing the distance between the gun and the microphone in Dealey Plaza (213 feet) by the speed of sound. For echoes produced at the corners of structures, the measurement procedure was simple and direct. For example, the path of echo 2 in figure 5 consisted of two segments. As measured on the map, the segment. from the shooter to the diffraction point was 499 millimeters and from that point to the microphone was 92 millimeters. The total path length, 591 millimeters, when divided by the sound-speed constant (2921 mm/sec) yielded an echo travel time of 0.2024 second (202.4 msec). Subtracting the muzzle blast travel time from the echo travel time yielded an echo-delay time of 17.2 milliseconds. For an echo produced by a specular reflection, it was necessary first to locate the point at which the reflection would occur. Such reflections occur at that point on an echo-producing surface at which the total length of the echo path to that surface is a minimum. At that point, the reflecting surface will be tangent to an ellipse for which the locations of the gun and the microphone are the locii and the total length of the echo path is equal to the sum of the radii. The required ellipse was easily generated by the following procedure. First, a nonextensible string was cut to a length greater than the probable length of the echo path on the topographical map. One end of the string was tied to a pin at the location of the gun and a portion of the string near its other end was wrapped tightly around a pin at the location of the microphone. The string was then pulled toward the reflecting surface by the point of a pencil. With the string drawn taut, the pencil was moved so that its point drew an arc on the map in the region of the line that represented the reflecting surface. The length of the string was then adjusted until the arc was just tangent to the line. The point at which the arc touched the line was the desired point of reflection. The path from the gun to the point of reflection and then to the microphone (the echo path) was then measured. The total distance of the echo path divided by the speed of sound was the echo travel time. Subtracting from it the muzzle blast travel time yielded the echo-delay time. 23 TABLE 1.-- List of structures in Dealey Plaza that would have produced echoes of sufficient strength to have been recorded on the DPD tape Object No. Identification 1 .......... South shelter: South door, east post. 2 .......... South shelter: East door, south post. 3 .......... South shelter: East door, north post. 4 .......... North shelter: South door, west post. 5 .......... North shelter: South door, east post. 6 .......... North shelter: East door, south post. 7 .......... North shelter: East door, north post. 8 .......... Wall "A." 1 9 .......... Wall "A": Corner 1. 10 .......... Wall "A": Corner 2. 11 .......... Column "A"2 Southwest corner. 12 .......... Wall "B"3 Corner 1. 13 .......... Wall "B": Corner 2. 14 .......... Column "B"4: West corner. 15 .......... Wall at the north end of the reflecting pool. 16 .......... DCRB: Southwest corner. 17 .......... DCRB: Northwest corner. 18 .......... DCRB: West wall (front of building). 19 .......... DCRB: Roof edge on west wall. 20 .......... DCRB: Southwest corner. 21 .......... New DCCCB: Northwest corner. 22 .......... DCRB--New DCCCB: Alley wall between buildings. [1] Wall "A" is a concrete wall on the north side of Elm St. that runs in an eastwest direction. Corners 1 and 2 are at the east end of the wall. The direction of the wall changes from east to northeast at corner 1, and from northeast to north at corner 2. [2] Column "A" is a concrete column on the north side of Elm St. near the intersection with Houston St. [3] Wall "B" is a concrete wall on the south side of Elm St. near the reflecting pool. It runs in a generally north-south direction. Corners 1 and 2 are at the northern end of the wall. The direction of the wall changes from north to northeast at corner 1 and from northeast to east at corner 2. [4] Column "B" is a concrete column on the south side of Elm St., at the northern end of Wall "B." TABLE 2.--List of echo paths used in the predictions of echo-delay times Echo producing objects Path No.: (Identification numbers) 1 ............................................................. 1 2 ............................................................. 2 3 ............................................................ 9 4 ............................................................ 2,8 5 ............................................................ 10 6 ............................................................ 5 7 ............................................................ 4 8 ............................................................ 6 9 ............................................................ 7 10 ............................................................ 12 11 ............................................................ 13 12 ............................................................ 14 13 ............................................................ 3,13 14 ............................................................ 3,14 15 ............................................................ 3,15 16 ............................................................ 16 17 ............................................................ 8,13 18 ............................................................ 19 19 ............................................................ 18 20 ............................................................ 21 21 ............................................................ 22 22 ............................................................ 4,19 23 ............................................................ 6,19 24 ............................................................ 20 25 ............................................................ 17 26 ............................................................ 23 24 TABLE 3.--MEASURED AND PREDICTED DELAY TIMES OF ECHOES FOR A GUNSHOT FIRED ON AUG. 20. 1978 [in milliseconds] ---------------------------------------------------------------------- Echo-delay time [1] Echo-------------------------- Echo path travel time Predicted Measured Deviation ---------------------------------------------------------------------- 1......... 192.3 7.0 7.3 0.3 2......... 196.0 10.8 11.2 .4 3......... 198.6 13.4 13.1 .3 4......... 201.7 16.5 16.9 .4 5......... 202.4 17.2 16.9 .3 6......... 213.0 27.8 28.3 .5 7......... 213.0 27.8 29.8 2.0 8......... 215.4 30.1 29.8 .3 9......... 218.1 32.9 32.9 0 10........ 228.4 43.2 42.3 1.1 11........ 229.4 44.7 45.6 .9 12........ 232.5 52.3 52.9 .6 13........ 243.4 58.2 60.0 1.8 14........ 252.7 67.5 68.3 .8 15........ 259.9 74.7 76.9 2.5 16........ 267.1 81.9 82.5 .6 17........ 267.4 82.2 83.1 .9 18........ 451.6 266.7 266.6 .1 19........ 455.0 269.8 269.2 .6 20........ 458.1 272.9 272.2 .7 21........ 469.2 284.0 282.3 1.7 22........ 482.8 297.6 297.7 .1 23........ 482.8 297.6 297.7 .1 24........ 487.2 302.0 303.2 1.2 25........ 497.8 312.6 313.0 .4 26........ 541.3 356.1 354.0 2.1 ---------------------------------------------------------------------- [1] For the calculated locations of the gun and the microphone, the muzzle blast travel tive is computed to be 185.2 ms. Using the methods described above, 96 echo paths were defined for echo-producing objects."' For some of these paths, the muzzle blast sound bounced on more than one echo-producing object. The echo-producing objects and echo paths are listed in tables 1 and 2. The travel times and the delay times for the predicted echoes are listed in table 3. Also listed are the echo-delay times determined by analysis of the time waveforms of the sounds received at microphone 4 of array 3 for the shot fired by the DPD shooter from the grassy knoll. These waveforms, which are shown in figure 6, were obtained by playing back the recording of the sounds that were picked up by the microphone, modifying the reproduced signal so as to approximate the effect that a microphone of the type used by the DPD in 1963 would have had on the signal, and then graphing the resulting signal. A 60-Hz tone that was recorded in one segment of the recording made during the testing in August 1978 made it possible to calibrate the time scale of the graph at 1 millisecond per millimeter. The first waveform appearing in the graph, the large peak at the left-hand side, corresponds to the supersonic shockwave of the rifle bullet. The second large peak is the waveform of the muzzle blast. Following it, with generally diminishing heights, are the waveforms of the echoes of the muzzle blast. The delay time of each echo was determined by direct measurement of the distance from the leading edge of the muzzle blast waveform to that of the echo. The numbered peaks shown in this figure correspond to the predicted echoes identified in table 3. The deviations between the predicted and measured echo-delay times listed in table 3 were in part due to small errors in the locations of the -------------------------------------- *At the time of the presentation of our findings on Dec. 28, 1978 22 echo paths had be defined. After that date, four additional paths were defined. 25 gun and the microphone. The microphone location was determined from a map of Dealey Plaza that showed where microphones were to be placed during the reconstruction experiment. However, the scale of the map, 1 inch equal to 40 feet, limited the measurement accuracy to about plus or minus 2 feet. Therefore, the actual location of the microphone may have deviated from the indicated one by a foot or two. Similarly, there were no measurements taken of the exact location where the DPD shooter stood as he fired each shot from the grassy knoll. Consequently, it was likely that the gun and the microphone locations FIGURE 6 FILTERED WAVEFORMS OF GUNSHOT SOUNDS RECEIVED AT MICROPHONE 4 OF ARRAY 3 that were used for the echo-delay time predictions were slightly in error and that if these positions were adjusted correctly, the resulting predictions would be closer to the measured echo-delay time. An analysis of the data listed in table 3 shows that the assumed locations were sufficiently accurate for the purpose of this test. The average absolute difference between the predicted and measured echodelay times was 0.8 millisecond. The standard deviation of predicted 26 delay times about this average was 0.7 millisecond. These results are well within the accuracy required of the echo prediction procedure. 5.0 COMPARISON OF THE SEQUENCE OF IMPULSES ON THE DPD RECORD- ING WITH SEQUENCES OF PREDICTED ECHOES 5.1 Prediction of echoes for November 22, 1963 Using the techniques described in section 4, we predicted echoes and echo-delay times for gunshot sounds that would have been heard in Dealey Plaza at 12:30 p.m. on November 22, 1963. The predictions were made given the following conditions: (1) The air temperature was 65(deg)F (with a possible error of 3(deg )F); (2) the gun was somewhere along the wooden stockade fence on the grassy knoll; (3) the microphone was somewhere in the region of interest on Elm Street (see section 4.1.3) and moving with the motorcade at a speed of about 11 miles per hour; and (4) the echo-producing objects were the same as those identified in table 1. The procedure that was used to predict echoes required a few more steps than the method described in section 4. Since the conditions required the microphone to be moving on Elm Street at a speed of 11 miles per hour, the location of the microphone on the map had to be moved in a similar manner. First, a location was specified on the map at which the microphone received the muzzle blast. Then, the microphone was moved along a path corresponding to the path it would have traveled on Elm Street during the time it received all of the predicted muzzle blast echoes. The location of the microphone at the time it would have received each particular echo was determined by calculating the distance the microphone would have moved from the initial position at a constant speed of 11 miles per hour during an interval equal to the echo traveltime. Small deviations about this estimated distance (for example, - +1 millimeter) did not materially affect the predicted echo travel time. The predicted echo-delay times were then obtained by the procedure described in section 4. 5.2 Correction of time delay measurements. The delay times of the impulse sounds on the DPD recording were measured directly from a graph of the sequence of impulse waveforms, such as the one shown in figure 3. To simplify the measurement of time intervals, the graph was plotted with a time scale of 1 millisecond per millimeter (1 msec/mm). However, before the measurements could be used, they had to be multiplied by a time-correction factor to correct for an error in the speed of the DPD Dictabelt. machine. As was shown in the BBN analysis, the DPD recorder was running slow at the time the recording was made. Consequently, when the recording is played back at the faster, correct speed, the recorded impulse sounds will be heard closer together than they actually were at the time the recording was made. This error could be corrected by multiplying the time intervals measured on the graph by a time-correction factor. The BBN analysis showed that between 12:22 p.m. and 12:37 p.m., the average speed of the recorder was 0.95 of correct speed. The actual speed at any time during this interval could have been from 0.94 to 0.96 of true speed. Accordingly, the time-correction factor could range from 1.04 to 1.06. An adjustment in the measurement of impulse delay times would also be necessary if the temperature in Dealey Plaza at, 12:30 p.m. on 27 November 22, 1963, was not 65 F, as was initially assumed. The computed delay time of each predicted echo would be in error by about 0.1 percent for each 1 F difference between the true temperature and the assumed value of 65 F. The effect on the predicted echoes would be to scale their spacing from what they should be. For example, if the temperature was more that 65 F, the computed echoes would be spaced more widely than they should be. Since it was not likely that the assumed temperature differed from the true temperature by more that 10 F, the factor for correcting temperature errors would range only from 0.99 to 1.01. Assuming that the differences in temperature and recorder speed occured in such a way as to compound on another, the combined factor that would correct for both recorder speed and temperature at the same time could range from 1.03 to 1.07. Because we knew that the range of the correction was 1.03 to 1.07, theoretically we could use any value between 1.03 and 1.07 to adjust the measured time intervals between the impulses on the DPD recording. Because any value between 1.03 and 1.07 was theoretically valid, it was permissable to choose the value between those livits that created the best match between the impulse and echo sequences. By fitting the DPD tape recorded impulse sequence to our predicted echo sequences, we found that a time-correction factor of 1.043 gave the best match, and we therefore used that factor. TABLE 4.--MEASURED DELAY TIMES OF IMPULSES AND PREDICTED DELAY TIMES OF GUNSHOT ECHOES FOR NOV. 22, 1963. [in milliseconds] ---------------------------------------------------------------------- Echo Echo Impulse Echo path travel time delay time delay time Deviation ---------------------------------------------------------------------- 1......... 202.4 6.5 6.3 0.2 2......... 206.8 10.9 10.5 .4 3......... 211.0 15.1 14.7 .4 4......... 214.7 18.8 19.3 .5 5......... 217.0 21.1 20.1 1.0 6......... 224.3 28.4 27.4 1.0 7......... 225.2 29.3 30.3 1.0 8......... 227.1 31.2 31.6 .4 9......... 230.6 34.7 34.1 .6 10........ 244.1 48.2 48.7 .5 11........ 241.5 45.6 45.4 .2 12........ 250.3 54.4 54.2 .2 13........ 255.2 59.3 59.7 .4 14........ 266.0 70.1 69.4 .7 15........ 273.4 77.5 77.4 .1 16........ 281.8 85.9 85.3 .6 17........ 276.7 80.8 80.2 .6 18........ 473.9 278.0 278.6 .6 19........ 479.8 283.9 283.7 .2 20........ 479.8 283.9 283.7 .2 21........ 489.1 293.9 292.1 1.1 22........ 506.8 310.9 310.5 .4 23........ 507.9 312.0 312.4 .4 24........ 509.6 313.7 313.1 .6 25........ 524.0 328.1 327.5 .6 26........ 565.0 369.1 369.2 .1 ---------------------------------------------------------------------- [1] For the calculated locations of the gun and the microphone, the muzzle blast travel tive is computed to be 195.9ms. 5.3 Comparison of the impulse and echo sequences The sequence of predicted echo-delay times that best matched the sequence of impulse-delay times, computed as described above, is listed in table 4. The numbered peaks shown in figure 7 correspond to the 28 predicted echoes identified in table 4. The average absolute difference between the impulse-delay times and the corresponding echo-delay times is 0.5 millisecond, and the standard deviation of impulse-delay times about this average is 0.3 millisecond. The location of the gun and the path of the microphone for which these predicted echoes were obtained are shown in figure 8. The microphone is initially located 97 feet south of the TSBD. and 27 feet east of the southwest corner of the TSBD. The path of the microphone, as it received the muzzle blast and its echoes, extends for about 6 feet FIGURE 7 IMPULSES ON THE DPD RECORDING ASSOCIATED WITH ECHOES 29 FIGURE 8 LOCATION OF THE GUN AND PATH OF THE MICROPHONE COMPUTED FOR NOVEMBER 22, 1963 along Elm Street. The uncertainty in the initial position is +/- 1 foot, which corresponds to the accuracy of measurements made on the topographical survey map. The gun is located about 8 feet to the left of the corner of the wooden stockade fence on the grassy knoll. If the gun is moved along the fence from this location, the delay times of the muzzle blast echoes changes. However, for movements up to +/- 5 feet, these changes can be reduced to less than 1 millisecond by making a small adjustment in the initial location of the microphone. The data in table 4 suggest that the sequence of impulses on the DPD recording is very similar to the sequence of predicted echoes. A visual comparison indicates that almost all of the impulses and echoes coincide within a window of +/-1 millisecond. However, such an examination can be deceptive. It does not take into account the impulses that 30 do not coincide with echoes, or the echoes that are not matched by impulses of even minimal amplitude. For these reasons, a more appropriate method of comparison was to compute the binary correlation coefficient of the sequences. 5.4 Factors affecting the selection of impulses and echoes for correla- tion Ideally, a correlation of the impulses and the predicted echoes would have included all of the impulses evident in the waveforms of figure 7 and all of the predicted echoes. However, some of the impulses must have represented components of the background noise. To minimize the number of noise impulses that might be included in the correlation calculation, only those impulses that were greater than the average peak level of the background noise were counted. This required limiting the predicted echoes that were included in the correlation calculation to those that, would have been recorded at a level above that of the background noise. To identify these echoes and impulses, it was necessary to consider, first, the relative strengths of predicted echoes near the microphone, and then the way in which the DPD radio dispatching system would have altered both the relative strengths of the echoes as recorded and the recorded level of the background noise. 5.4.1 Relative strengths of echoes near the microphone location. The relative strengths of the predicted echoes at locations along the path traveled by the microphone would be similar to those of the actual echoes of a muzzle blast that were recorded during the acoustical reconstruction experiment at the nearby location of microphone, 4 in array 3 (see fig. 5). The strengths of echoes received at these nearby locations would not differ by more than a few decibels. Therefore, the relative strengths of the predicted echoes in the vicinity of the moving microphone could be taken to be the same as those received by microphone 4. 5.4.2 Effects of the DPD radio dispatching system on the relative strenghts of recorded echoes. The DPD radio dispatching system contained a circut that would have greatly affected the relative strengths of the recorded echoes of a muzzle blast. This circuit, the automatic gain control (AGC), limited the range of variations in the levels of signals by reducing the levels of received signals when they were too strong and increasing their levels when they were, too weak. It responded very rapidly to a sudden increase in the level of a signal, but comparatively slowly to q, sudden reduction in a signal level. Consequently, the response of the AGC to the sound of a muzzle blast would greatly reduce the recorded levels of echoes and background noise received shortly afterward. Progressively during the next 100 milliseconds, the AGE would allow the recorded levels of received signals to increase until full amplification was finally restored. The effect on the predicted echoes would be to make the recorded levels of late-arriving echoes very nearly the same as those of the early ones. Concurrently, the recorded background noise would gradually rise to its level before the muzzle blast was received. A different but also significant effect on the relative strengths of the recorded echoes would have been caused by the motorcycle windshield. On the DPD motorcycles, the microphone was usually mounted on a 31 bar directly behind the windshield. Sounds arriving from the front of the motorcycle would have diffracted around the windshield and in doing so would have lost strength. As determined by experiment, the windshield of a 1960's Harley Davidson motorcycle attenuated gunshot sounds received from in front of the motorcycle by from 3 decibels to 6 decibels. The amount of attenuation depended on how close the microphone was to the windshield. Obviously, sounds received from the sides and rear of the motorcycle would not be affected by the windshield. 5.5 Correlations of impulse and echo sequences The selection of impulses for the calculation of the binary correlation coefficient depends directly on the noise level to which the heights of the impulses are compared. This level can be set, as in figure 2, at the average peak level of the recorded noise immediately adjacent to the recorded impulses. This approach, however, presumes that the noise level is the same during the impulse segment as it is in the adjacent segments of the recording. As was discussed above, the level of the noise recorded during the first 50 milliseconds following a muzzle blast will be greatly reduced. Consequently, an alternative would be correspondingly to lower the level to which the impulses are compared during this 50-millisecond period. Both approaches to setting the amplitude comparison level were used, each in a separate calculation of the binary correlation coefficient. For the first calculation, the amplitude comparison level was set as in figure 2. Taking all of the factors discussed in section 5.4 into account, we found that 13 gunshot sounds (the muzzle blast and 12 of the predicted echoes) would have been loud enough to have been recorded at a level above the background noise. Eleven of these sounds coincided, within a millisecond window, with impulses that exceeded the amplitude comparison level. Including the leading impulse, which was identified as the muzzle blast, a total of 15 impulses exceeded this level. The binary correlation coefficient was calculated as the number of gunshot sounds and impulses that coincided (11) divided by the square root of the product of the number of selected impulses (15) and the number of selected gunshot sounds (13). For these data, the binary correlation coefficient was calculated to be 0.79. For the second calculation of the binary correlation coefficient, the delay time range over which impulses and echoes were compared was limited to the first 50 milliseconds following the muzzle blast, since this was the range in which the AGC would have had greatest effect. (It is also the range in which most of the echoes arriving from the front of the motorcycle occurred.) In this calculation, the amplitude comparison level was reduced to one-fourth of its value during the previous calculation, which placed it at a level just above that of very small peaks among the waveforms of the recorded impulses. Eighteen impulses exceeded this level. So would have the muzzle blast and all echoes that were predicted to occur in the delay time range up to 50 milliseconds. Eleven of these sounds coincided, within +-1 millisecond, with one or another of the selected impulses. These coincident impulses and echoes, 12 gunshot. sounds, and 18 impulses-resulted in a computed binary correlation coefficient of 0.75. 32 5.6 The probability that the recorded impulses are not gunshot sounds. The high degree of correlation between the impulse and echo sequences does not preclude the possibility that the impulses were not the sounds of a gunshot. It is conceivable that a sequence of impulse sounds, derived from nongunshot sources, was generated with time spacings that, by chance, corresponded within one one-thousandth of a second to those of echoes of a gunshot fired from the grassy knoll. However, the probability of such a chance occurrence is about 5 percent.* This calculation represents a highly conservative point of view, since it assumes that impulses can occur only in the two intervals in which echoes were observed to occur, these being the echo-delay range from 0 to 85 milliseconds and the range from 275 to 370 milliseconds. However, If the impulses in the DPD recording were not the echoes of a gunshot, they could also have occurred in the 190-millisecond timespan that separated these two interva]s. Taking this timespan into account, the probability becomes considerably less than 5 percent that the match between the recorded impulses and the predicted echoes occurred by chance. Thus, the probability is 95 percent or more that the impulses and echoes have the same source a gunshot, or a sound at least as sound as a gunshot, from the grassy knoll. Stated differently, the odds are less than 1 in 20 that the impulses and echoes were not caused by a gunshot from the grassy knoll, and at least 20 to 1 that they were. ----------------------------------------------- *See the BBN report No. 3947. 33 Report No. 3947 Analysis of Recorded Sounds Relating to the Assassination of President John F. Kennedy James E. Barger, Scott P. Robinson, Edward C. Schmidt, and Jared J. Wolf January 1979 Prepared for: Select Committee on Assassinations Bolt Beranek and Newman Inc. 50 Moulton Street Cambridge, MA 02138 34 FOREWORD On May 12, 1978, the House Select Committee on Assassina- tions asked Bolt Beranek and Newman Inc. (BBN) to conduct a preliminary review of the following material: - Tape recordings reportedly made of the sounds in Dealey Plaza around 12:30 pm on November 22, 1963 - Transcripts of the testimony of earwitnesses who were in the Plaza at that same time. The purpose of this review was to determine which, if any of this material constituted potential evidence with respect to the gunfire associated with the assassination of President John F. Kennedy. The review established that (1) only two of the recordings constituted potential evidence and (2) a statistical analysis of the earwitness testimony could reveal whether the concept of one rifle is consistent with these individual accounts. The two tapes found to be made of the events surrounding the assassination were records from Channels 1 and 2 of the Dallas Police Department's (DPD) radio dispatching system. The Channel 1 tape contains a continuous record of the sounds transmitted between 12:28 and 12:34 pm over a DPD motorcycle radio stationed in Dealey Plaza. The Channel 2 tape is an particular, communications between the Chief of the Dallas Police Department, who occupied the car immediately preceding the Presidential limousine in the motorcade, and the Channel 2 Dispatcher at DPD headquarters. iii 35 An initial analysis of a portion of the Channel 1 tape did not rule out the possibility that the recording contained the sounds of gunfire. The House Committee therefore authorized BBN to conduct studies both of the DPD tapes and of the ear- witness testimony. This report describes the results of an analysis of the tapes. The study of earwitness testimony is reported under separate cover.* ______ *Green, D.M., "Analysis of Earwitness Reports Relating to the Assassination of President John F. Kennedy," BBN Rep. 4034, January 1979. iv 36 ACKNOWLEDGMENT The authors gratefully acknowledge the fine contributions made to this study by Joseph F. Colaruotolo, Daniel N. Kalikow, Nancy M. McMahon, Theodore L. Rhyne, and Leo A. Sledjeski. v 37 TABLE OF CONTENTS page FOREWORD .................................................. iii ACKNOWLEDGMENT ............................................ v LIST OF FIGURES ........................................... ix SECTION 1. INTRODUCTION AND SUMMARY ................... 1 1.1 Initial Analysis ...................... 2 1.2 Screening Tests ....................... 4 1.3 Further Analysis ...................... 5 1.4 Conclusions Based on Results of the Acoustical Reconstruction.............. 7 1.5 Independent Analytical Extension of the Reconstruction Test ................... 8 1.6 Findings .............................. 9 2. NATURE OF RADIO-TRANSMITTED SOUNDS OF GUNFIRE 12 2.1 Overview .............................. 18 2.2 Propagation Over the Direct Path....... 18 2.3 Propagation Over Reflected Path........ 18 2.4 Propagation Over Diffracted Paths...... 19 2.5 Propagation Over Scattered Paths....... 20 3. RESULTS OF EXAMINING AND PROCESSING THE DPD CHANNEL 1 TAPE.............................. 22 3.1 The Unprocessed Waveform Data.......... 22 3.2 Spectrographic Analysis................ 25 3.3 The Filtered Waveform Data............. 25 4. SCREENING TESTS............................. 30 4.1 Time of Occurence...................... 30 4.2 Uniqueness of the Impulse Patterns..... 33 vii 38 TABLE OF CONTENTS (Cont.) 4.3 Time Span of the Impulse Patterns...... 35 4.4 Shape of Impulses...................... 35 4.5 Amplitude of Impulses.................. 37 SECTION 5. ACOUSTICAL RECONSTRUCTION IN DEALEY PLAZA... 40 5.1 Nature of the Test..................... 40 5.2 Problems To Be Solved by the Acoustical Reconstruction Test.................... 56 5.3 Results of the Acoustical Reconstruction Test................................... 60 5.4 Conclusions about the Acoustical Restruction Test....................... 62 6. ADDITIONAL RELEVANT SOUNDS ON THE DPD CHANNEL 1 TAPE.............................. 70 6.1 Bell................................... 70 6.2 Sirens................................. 72 6.3 Voice and Other Remote Transmissions... 72 7. REVIEW OF AN INDEPENDENT ANALYSIS OF THE POSSIBLE THIRD SHOT......................... 74 APPENDIX A. COMPUTER SIGNAL PROCESSING.................. A-1 B. RADIO TRANSMISSION OF GUNFIRE SIGNALS....... B-1 C. ANALYSIS OF FALSE ALARMS IN THE CORRELATION DETECTION TEST.............................. C-1 viii 39 LIST OF FIGURES page Figure 1. Loci of muzzle blast and shock waves at two times after firing of bullet................. 13 2. Echo patterns caused by direct, reflected, diffracted, and scattered impulsive sounds in an urban environment......................... 14 3. Muzzle blast and shock waveforms for Mannlicher- Carcano and M-1 rifles....................... 17 4. Waveforms record from Channel 1 transmitter with stuck microphone........................ 24 5. Spectorgrams from waveforms recorded from Channel 1 transmitter with stuck microphone.. 26 6. Adaptive filtered waveforms recorded from Channel 1 transmitter with stuck microphone (130 to 141 sec)............................. 28 7. Adaptive filtered waveform recorded from Channel 1 transmitter with stuck microphone (141 to 150 sec)............................. 29 8. Least-square error fits to Channel 2 Dispatcher's time annotations showing times of DPD Chief's radio transmissions.......................... 32 9. Least-square error fit to Channel 1 dispatcher's time annotations showing time of first set of gunfire-like events.......................... 34 10. Muzzle-blast and shock waveforms transmitted by a police radio similar to the one used by DPD motorcycles for several different loudnesses.. 36 11. Level of transmitted waveforms as a function of waveform level at the microphone.............. 39 12. Microphone locations at Dealey Plaza.......... 41 13. Comparison of test echo patterns produced by both Western and Norma ammunition fired from TSBD (muzzle withdrawn) at target no. 3 and received at array 3, microphones 7, 8, and 9........... 42 ix 40 LIST OF FIGURES (Cont.) page Figure 14. Echo pattern for shot 2 (TSBD, muzzle with- drawn, target no. 1) received at array 2, microphones 4, 5, and 6....................... 45 15. Echo pattern for shot 7 (TSBD, muzzle with- drawn, target no. 3) received at array 2, microphones 4, 5, and 6....................... 46 16. Echo pattern for shot 8 (knoll, target no. 3) received at array 3, microphones 4, 5, and 6.. 47 17. Echo pattern for shot 6 (TSBD, muzzle exposed, target no. 3) received at array 3, microphones 4, 5, and 6................................... 48 18. Impulse pattern from stuck-transmitter recording beginning at time 137 sec........... 50 19. Impulse pattern from stuck-transmitter recording beginning at time 139 sec........... 51 20. Impulse pattern from stuck transmitter recording beginning at time 145 sec........... 52 21. Impulse pattern from stuck transmitter recording beginning at time 145.5 sec......... 53 22. Microphone positions along motorcycle route where high correlations were obtained, as a function of time. Estimated trajectories of motorcycle and of the Presidential limousine are shown from their positions indicated by the Hughes felm at the time the limousine turned down Elm St............................ 63 x 41 1. INTRODUCTION AND SUMMARY The House Select Committee on Assassinations authorized Bolt Beranek and Newman Inc. (BBN) to study two tape recordings made by the Dallas Police Department (DPD) on November 22, 1963 on Channels 1 and 2 of the DPD's radio dispatching system. Channel 1 is the channel ordinarily used to handle DPD radio traffic, and this channel is recorded continuously on a Dictabelt recorder. Channel 2, an auxiliary channel generally used to handle the additional radio traffic necessitated by special events, is recorded intermittently on a Gray Audograph recorder, as actuated by voice communications and time annotation. Frequent time annotations -- usually at 1-minute intervals are made by the radio dispatchers handling each of these channels. On November 22, 1963, during the time of President Kennedy's assassination, the radio of a DPD motorcycle, which may have been in the motorcade, was stuck in the transmitting mode on Channel 1 for approximately 5 minutes. During this time, the Chief of the Dallas Police Department, whose car immediately preceded the President's limousine in the motorcade, transmitted several messages concerning the progress of the motorcade over Channel 2. Channel 2 had been designated for use by DPD officers in the motorcade on November 22, 1963. Therefore, if the Channel 1 recording were to contain sounds of gunfire associated with the assassination, then at least one of the motorcycle radios used in the motorcade must have been incorrectly switched to Channel 1. Voice transmissions on both tapes were monitored for the call numbers of the 18 motorcycle officers in the motorcade. Six of the officers were heard to transmit on Channel 2; three on Channel 1.* The other nine did not make any transmissions, so cannot be determined which channel their radios were set for. ---------------------------------------------- *These three transmissions were made at about 2:10 pro, 4:39 pm, and 522 pro, all later times than the assassination. 1 42 1.1 Initial Analysis The questions to be addressed in the analysis of these tapes were: * Does the 5-minute segment recorded on Channel 1 contain the sound of gunfire? * If so, how many shots were recorded and from what location (or locations) did the shots originate? To begin with, if gunfire had been recorded on Channel 1, the analysis of that tape could be expected to reveal patterns of transient waveforms that would be generally characteristic of the shock wave produced by the bullet, of the loud and impulsive noise of the muzzle blast, and of echoes of each. It could further be expected that the major components of the shock wave would appear in the 1-kHz to 3.2-kHz frequency band. The initial analysis of the Channel 1 tape therefore con- sisted of filtering and recording the entire 5-minute segment through each of two filters designed to reveal the presence of any transient impulsive waveform patterns that might be masked by the repetitive loud noise of the motorcycle. The first was a bandpass filter that filtered out all sounds not contained within the frequency range extending from 1 kHz to 3.2 kHz. This range was known to contain the principal frequency com- ponents of the shock wave produced by the bullet and to contain relatively few components of motorcycle noise. The second filter was an adaptive Widrow LMS filter, which studies the repetitive nature of noise, estimates what it will be a short time later, and subtracts these noise components out, leaving transient events not anticipated by the filter. 2 43 The recorded outputs from both filters for the full 5 minutes were compared, examined, and plotted on a scale where 5 in. equals 1/10 sec. These plots revealed five impulse, patterns introduced by a source other than the motorcycle. Upon closer examination, all but one of the these patterns were sufficiently similar .to have had the same source, and the impulses contained in these patterns appeared to have shapes similar to the expected characteristics of a shock wave and of a muzzle blast. The remaining pattern was sufficiently differ- ent in amplitude and duration as to have been caused by a different source. The hypothesis to be tested, then, was that these four impulse patterns were caused by gunfire. Initially this hypothesis was subjected to five simple, but necessary, screen- ing tests: 1. Time of occurrence 2. Uniqueness of patterns 3. Time span between patterns 4. Shape of impulses within the patterns 5. Amplitude of impulses. Should the hypothesis then pass these tests, a sixth, more rigorous, est would be applied. This final test would require an acoustical reconstruction of the circumstances of the original gunfire in Dealey Plaza to reveal the relative times that muzzle blast and shock wave impulse, together with their echoes, would arrive at microphones located where the motorcycle radio might have been. 44 1.2 Screening Tests The five screening tests were designed to determine whether the characteristics of the four impulse patterns corresponded both to other evidence and to the characteristics of actual gunfire. 1 Did the impulse patterns occur at the same time the shots were actually fired? Yes. Stopwatch timing and examination of both tapes placed the time of the shot and the time of onset of the first pattern of waveforms within 35 sec of each other. The margin of acceptable time difference was 60 sec, since the two time clocks used by the two dispatchers were synchronized to within Just 1 minute. 2 Were these impulse patterns unique? Yes. Examination of the entire 5-minute segment did not reveal sufficiently similar impulse patterns elsewhere on the tape to discount gunfire as the source of these four patterns. 3. Did the time span between the patterns correspond to other evidence of intervals between shots? Yes. The intervals between the onset times of the four impulse patterns on the DPD tape with the frames on the Zapruder film showing bullet impact were compared. According to the Zapruder film, the time span between the earliest and the latest gunfirelike events recorded on Channel 1 had to be no less than 5.6 sec. The span between onset times of the first and the fourth patterns was 8.3 sec. 45 4. Did the shape of the impulse patterns resemble those generated by actual rifle fire? Yes. Tape recordings of test shots made with a MannlicherCarcano rifle were put through electrical circuits that mimicked those through which the 5-minute segment had been recorded. The shape of the impulse patterns on the Channel l tape approximates those produced by the test shots. 5. Did the range of amplitude (loudness) of the impulse patterns resemble that of the echo patterns produced by the test shots? Yes. Processing the echo patterns of the test shots through a radio receiver like that used in the DPD recording system showed similar compression of the range of amplitude of recorded signals with respect to the range of the signals fed into the receiver. The answers to these five questions neither proved nor disproved the possibility that the four impulse patterns on the Channel l tape had been caused by gunfire. A more rigorous analysis was required to determine with some confidence whether or not these patterns had been caused by gunfire. 1.3 Further Analysis The gunfire and the potential motorcycle radio positions on November 22, 1962 were acoustically reconstructed on August 20, 1978 in Dealey Plaza. The sounds were subsequently processed into echo patterns, each one representing the unique "fingerprint" of gunfire sounds as heard at one location when a weapon is fired from one place to one target. The Channel 1 recording made at the time of the assassination had been similarly processed into sound impulse patterns. However, the 46 Channel 1 impulse patterns were like badly smudged "fingerprints," because of the extremely noisy environment in which the original recording had been made. The echo patterns were compared to the impulse patterns to see if any of the clear "fingerprints" obtained during the reconstruction matched any of the smudged "fingerprints" on the Channel l recording. The matching process was a binary correlation detector, a simple but powerful signal-detection scheme that is conducted mathematically. Several echo patterns from the acoustical reconstruction matched sufficiently well with the four impulse patterns that we were able to place the motorcycle behind the Presidential limousine, at distances varying from 120 ft to 160 ft. The correlation detector indicated that four shots may have been fired, as follows: l. time 0.0 sec --one shot from the Texas School Book Depository (TSBD) aimed between the limousine positions seen in frames 160 and 313 of the Zapruder film 2. time 1.6 sec -one shot from the TSBD aimed near the limousine position seen in frame 313 3. time 7.8 sec - one shot from behind the fence on the knoll aimed near the limousine position seen in frame 313 4. time 8.3 sec -one shot from the TSBD aimed between the limousine position seen in frame 313 and the triple underpass. 47 1.4 Conclusions Based on Results of the Acoustical Reconstruction The conclusions drawn from the results of the matches obtained by our analysis were presented at the public hearing before the committee on September 11, 1978. Essentially, we had concluded that the motorcycle had indeed been in the motorcade and that possibly four shots had been fired at President Kennedy. The reason that our findings with respect to the four shots were stated in terms of probabilities is as follows. The correlation detector produced several false alarms that could be identified as such. These false alarms are spurious matches caused by uncertainty of the exact motorcycle position with respect to the known positions of microphones used in the reconstruction test. Therefore, some of the correlations that indicated the four shots must also be suspected as false alarms. This uncertainty introduced by the suspected false alarms can be expressed as a set of probabilities on the possible true outcomes. These probabilities were calculated from the judgment that each match has a 50% probability of being a false alarm and from the assumption that each match is an independent observation. Thus, the individual probabilities that the shots occurred at each of the four times are: Shot 1. 88% based on three matches Shot 2. 88% based on three matches Shot 3. 50% based on one match Shot 4. 75% based on two matches The probability that the four possible shots found by the correlation detector include at least two correct detections is high, about 96%. The probability that there are three correct 7 48 detections is lower, about 75%. The probability that all four are correct is only about 29%. The combined probability that there are three correct detections, and that the third (knoll) shot is among them is about 47%. 1.5 Independent Analytical Extension of the Reconstruction Test. The Committee sought to have the uncertainty in the test results reduced, particularly with respect to the 50% probability of the third (knoll) shot. Professor Mark Weiss and Mr. Ernest Aschkenasy of Queens College were authorized by the Committee to conduct an analytical extension of our acoustical reconstruction test. They first identified the objects in Dealey Plaza that caused each echo that appeared in the echo pattern we had found to indicate the possible third (knoll) shot. Next, they calculated how this echo pattern would be modified for receivers in the neighborhood of the microphone from which the echo pattern was obtained. Finally, they were able to show that 10 echoes of 12 in one of their calculated echo patterns matched with 10 sound impulses of 14 on the DPD tape recording each one to an accuracy of +/- l ms. The first of the 10 matching impulses was found to occur 7.6 sec after the first impulse indicating the first shot. We examined the results of this independent study and Judged both the technique and the parameters they used to be correct in every detail. We further concluded that the odds were only about 1 in 20 that their very precise match could have been achieved by chance - i.e., if the 14 sound impulses on the DPD tape were all noise and did not include echoes from a knoll gunshot. For this reason, We conclude that there is a 95% probability that there was a gunshot fired from the knoll at about 7.6 sec after the first one. 49 1.6 Findings The results of our analysis of the tape-recorded evidence, together with the independent analysis of the echo-pattern match with the third (knoll) shot, permit the following findings: 1. The recorded sounds on Channel 1 of the Dallas Police radio dispatch system probably include the sounds of four gunshots fired in Dealey Plaza at about 12:30 pm on November 22, 1963. 2. The recorded gunshot sounds were sensed and transmitted by a police radio mounted on a motorcycle in the motorcade and positioned at distances ranging from 120 ft to 160 ft behind the Presidential limousine. 3. The first probable shot was fired at about 12:30:47 from the TSBD. The motorcycle position was then On Houston St. having only about 3 sec earlier slowed in preparation for the left turn onto Elm St. No shock wave indicating a supersonic projectile is seen as a precursor to the sounds of the muzzle blast, and none is expected, owing to the position of motorcycle with respect to the expected trajectory of the bullet. Therefore, no conclusion can be drawn about whether this first acoustic disturbance was due to a rifle orto a sound impulse as loud as the report of a rifle. However, the sound did originate in the vicinity of the sixth floor of the TSBD. 4. The second probable shot was fired about 1.6 sec after the first one(,) also from the TSBD. At this time the motorcycle was just at the corner of Houston and Elm. Again, no shock wave is seen as a precursor to the sounds of the muzzle, and, again, none is expected. 50 5. The third probable shot was fired about 7.6 sec* after the first one, and it was fired from behind the fence upon the "grassy knoll". At this time, the motorcycle was proceeding westward on Elm St. about 80 ft west of the intersection with Houston St. An apparent shock wave is seen as a precursor to the sounds of the muzzle blast. In as much as a supersonic projectile would show such a precursor when the motorcycle is in this position, the third shot is probably from a rifle. 6. The fourth probable shot was fired about 5.3 sec. after the TSBD. The motorcycle was on Elm St. about 90 ft west of the intersection with Houston St. An apparent shock wave is seen as a precursor to the sounds of the muzzle blast. Since the trajectory of the bullet would have been over the motorcycle, such a precursor would be expected for a rifle shot. Therefore, the fourth shot is probably from a rifle. 7. Additional police radio transmissions are intermittently probable shots. These transmissions contribute a few electrical impulse to the noise background in which the impulses of gunfire are set. However, these noise impulses are too few in number to have a material effect o n the accuracy by which the echo patterns of the acoustical reconstruction match the impulse patterns on the DPD tape. ----------------------------------------- *This time was obtained from the independent study of Weiss and Aschkenasy, and it differs by about 0.2 sec From the time obtained by our correlation detector. 51 These findings were presented at public hearing before the Committee on December 29, 1978. At that hearing, Officer H.B. McLain of the DPD testified that he had been riding his motorcycle on the left-hand side of Houston St., approaching Elm St. when he heard a single shot. After the hearing, he said that he remembered that he had turned on his siren shortly after the assassination and moved with the motorcade to the hospital. However, the appearance of McLain in photographs taken in Dealey Plaza Just after the assassination suggests he did not leave the area with the motorcade. Unless McLain turned on his own siren, the absence of the siren sound on the tape is consistent with McLain's behavior as documented in photographs and it may have been his motorcycle. Section 2 of this report describes the acoustical nature of gunfire -- i.e., what could be expected after appropriate filtering of the Channel 1 tape, if it did indeed contain the sound of gunfire. Section 3 reports the procedures used to process the tape and the results of this processing. Section 4 describes the five screening tests, and Sec. 5 reports the results of the acoustical reconstruction of gunfire in Dealey Plaza. Section 6 discusses additional relevant sounds on the Channel 1 recording. Finally, Sec. 7 describes our review of independent analysis of the match between our acoustical reconstruction and the sounds of the probable third shot. 11 52 2. NATURE OF RADIO-TRANSMITTED SOUNDS OF GUNFIRE 2.1 Overview The discharge of a rifle creates two sources of impulsive sound - the sound of the muzzle blast and the sound of the shock wave shed from the supersonic bullet as it travels at a speed greater than the speed of sound. Figure 1 illustrates the difference in how these two impulsive sounds travel through the air. The shock wave, for example, has a direct path of travel that resembles a cone, while the sound of the muzzle blast spreads spherically from the source. In addition to traveling at different speeds and in different ways, these impulsive sounds travel over several different paths before arriving at a receiver -- in this case, a microphone. Figure 2 illustrates these paths. The first sound impulses to arrive travel in a straight line from the source to the microphone; this sound path is called the direct (D) path. It includes reflections (D2) from impulses traveling the direct path and striking the ground very near the microphone. Later sound impulses arrive at the microphone after first reflecting from large surfaces, such as building facades and the ground; these sound paths are called reflected (R) paths. Even later sound impulses arrive at the microphone after first diffracting from the corners of buildings and the edges of other large objects; these sound paths are called diffracted (T, M, L) paths. A weaker set of sound impulses, arriving at the microphone just after the direct arrival, are scattered first by small objects such as poles, people, and automobiles. After striking these scattering objects, these weaker sound impulses arrive at the microphone over the scattered (S, P) paths. Finally, reflections 12 53 Fig. 1. LOCI OF MUZZLE BLAST AND SHOCK WAVES AT TWO TIMES AFTER FIRING OF BULLET. 54 Fig. 2. ECHO PATTERNS CAUSED BY DIRECT, REFLECTED, DIFFERACTED, AND SCATTERED IMPULSIVE SOUNDS IN AN URBAN ENVIRONMENT 55 from distant objects (U) arrive over various reflected paths, but these signals appear much later than those arriving by all the previously described paths. All sound impulses arriving at the microphone that are loud enough to be heard over the environmental noise would be transmitted over the radio connected to the microphone. In this case, the environmental noise consisted primarily of the very loud, repetitive noise made by the engine of a moving motorcycle. This noise was found to be only about 10 dB lower than the loudest gunfire impulse "recorded. Thus, only the very loudest gunfire sound impulses would actually be detectable above the engine noise. The loudest sound impulses from gunfire are considerably louder than the loudness of speech, for which the radio was designed to operate. These loud impulses overdrive the radio circuitry. Because of the limiting circuits in the radio transmitter, very loud sounds are recorded in distorted fashion and appear as much weaker signals than they really are. In fact, despite the difference in loudness of signals traveling over the several paths illustrated in Fig. 2, each is recorded as having about the same amplitude. After the sounds that were picked up at the microphone had been transmitted to the DPD radio receiver, the output of the receiver was recorded on a Dictabelt recorder. The circuitry of the receiver and the characteristics of the recorder also affected the transmitted signals. The recorded loudness of the sounds transmitted from the motorcycle radio with the stuck microphone were additionally affected somewhat by simultaneous transmissions from other officers in the motorcade. An FM radio receiver, such as the one in DPD headquarters, receives 15 56 best from the transmitting radio having the strongest transmitted signal and can accommodate at the same time all receivers whose transmitted signal strengths differ by less than the receiver capture ratio. Thus, the effects of severe environmental noise, Of the limiting circuitry of the radio transmitter, of simultaneous radio transmissions, and of the recording characteristics of a Dictabelt recorder were such that any waveforms that would emerge from an analysis of the tape would be severely distorted. What these waveforms would look like without such distortion is illustrated in Fig. 3. the upper portion of The waveforms shown in/this figure were produced by a Mannlicher-Carcano with Western Cartridge Co. ammunition and picked up by a microphone positioned 30 ft from the muzzle and 10 ft to one side of the bullet's trajectory. The muzzleblast waveform reveals a peak pressure impulse having a sound pressure level of 137 dB re 2x10 -5N/m2. For comparison, Fig. 3 also shows the corresponding waveforms for an M-1 rifle. Despite the differences in loudness (amplitude) from one weapon to the other, the shock wave and the muzzle blast can be seen to have characteristic shapes. Sounds processed from the Channel 1 tape could be expected to contain these shapes, but in distorted fashion. The shapes could be expected to be compressed in amplitude and to be accompanied by indications of overdriving of the radio circuits. They would also be accompanied by waveforms produced by the arrival of sound echoes from several sources, as described in the rest of this section. 16 57 FIG. 3. MUZZLE BLAST AND SHOCK WAVEFORMS FOR MANNLICHER-CARCANO AND M-1 RIFLES. 17 58 2.2 Propagation Over the Direct Path The distance from the muzzle in the TSBD to the nearest possible location of the motorcycle microphone is 60 ft and to the farthest possible location (at Houston and Main) is 260 ft. Loss in amplitude of the sound of the muzzle blast over the direct path is due principally to the spherical spreading of the sound as it travels outward from the source of gunfire. This weakening (attenuation) is accounted for by the quantity 20 log(D/30), where D is the length, in ft, of the path of travel. The estimated loudness of the muzzle blast at the nearest possibly motorcycle location is 137 - 20 10g(60/30), which is equal to 131 dB re 2x10 -5N/m(2). The estimated loudness of the muzzle blast at the farthest possible location is equal to 118 dB re 2x10 -5N/m(2). Thus, both the muzzle blasts and the shock waves would be received over the direct path with sound pressure levels greater than the approximately 100-dB limiting sound pressure levels of the motorcycle radio. The result would be both an indication of overdriving the system and a compression of the recorded amplitude. 2.3 Propagation Over Reflected Paths Ground reflections will always occur from below the microphone at the specular reflection point. Since the path length of the reflected path is only a few feet longer than for the direct path, the amplitude of ground-reflected sounds will nearly equal the amplitude of sounds arriving over the direct path. 18 59 Building reflections occur only when a building facade includes a specular reflection point for the source and microphone. This condition is met by the buildings on Houston St. for microphones located on Houston near Main St., and it is also met by the Post Office Annex for microphones located on Elm St. The path length for these reflections is the total distance from the source to the specular reflection point and then to the microphone. For microphones on Elm, the path length for reflections off the Post Office is about 1100 ft. The amplitude of such echoes is, therefore, estimated to be 137 - 20 log(1100/30) (= )106 dB re 2x10 -5N/m(2 )-- still loud enough to cause limiting by the radio. All reflected sounds, regardless of the reflecting surface, arrive at the microphone T seconds later than sounds traveling the direct path. T can be expressed as the ratio AD/C, where is the difference between path lengths in ft, and c is the speed of sound in ft/sec. At 65 deg F, c is 1123 ft/sec, and at 90 deg F, c is 1150 ft/sec. Sounds reflected from the Post Office occur about (1100-100)/1100, or about 0.9 sec later than the direct sounds. 2.4 Propagation Over Diffracted Paths The amplitude of sound diffracted by a corner of a building can be estimated as follows.* The ratio of diffracted sound pressure Pd to direct sound pressure Po can be written as: ------------------------ *See J.J. Bowman, T.B.A. Senior, P.L.E. Uslenghi, Electromagnetic and Acoustic Scattering by Simple Shapes, North-Holland Publishing Company, Amsterdam, 1969 (p. 274). 19 19 60 where 6 = r/r0, the distances from the corner to the source and from the corner to the microphone, respectively. The angle between arriving and diffracted rays of sound is 0 and k is the acoustic wavenumber. The function F is a number generally between 1 and 2. There are many corners that can cause diffractions. The corner of the Records Building is typical. The amplitude of a sound impulse diffracted from its corner and received at Houston and Elm would be about 30 dB lower than that of an impulse arriving directly from the source. Since the amplitude of the direct-path sound of the muzzle blast near Houston and Elm is about 131 dB re 2x10 -5N/m2, the amplitude of the diffracted impulse will be about lOl dB re 2x10 -5N/m2, still loud enough to be somewhat limited by the radio and to be quite audible. The total path lengths of diffracted sounds vary continuously between limits set by the direct path length and by the longest reflected path length. Thus, diffracted sounds should occur between the time of the direct arrival and the time of the arrival of the reflection from the Post Office. 2.5 Propagation Over Scattered Paths Objects small enough so that kd=2, where d is the nominal diameter of the object, will scatter sound in all directions. Substantial energy in the muzzle blast impulse is contained at frequencies near 500 Hz, where k = 2.8 ft -1. Thus, objects having a diameter of about l ft satisfy the scattering requirement. Such objects could be light poles, people, and motorcycles. 20 61 The loudness of scattered sound diminishes rapidly with increased distance from the scattering object. For this reason, only sounds scattered from objects fairly close to the microphone would be loud enough to be recorded. Scattered sounds loud enough to be picked up by the microphone would arrive just following strong direct, reflected, and diffracted sounds. These scattered arrivals tend to increase the apparent time interval in which the primary signals arrive. 21 62 3. RESULTS OF EXAMINING AND PROCESSING THE DPD CHANNEL 1 TAPE The first tape we received on May 12 from the Committee had a very scratchy overlay of needle noise, indicating that it was a very poor or multiple-generation dub of a recording. In july, the Committee gave us an electromagnetic tape recording that was identified as an original dub made by the DPD, as well as the original Dictabelt record. We then made our own dub on magnetic tape from the original Dictabelt record and compared our dub with that reportedly made by the DPD. We digitized both dubbed tapes - ours and that made by the DPD, plotted the outputs of the digitizing process, and found them to be virtually identical. In this way, we determined that the Dictabelt record was really the source of the data on the DPD-dubbed tape that we were using for analysis. On the DPD Channel 1 tape, there is an interval of about 5-minute duration, beginning a little after 12:28 pm, in which the radio traffic on this channel is disrupted by a continuous transmission by some remote transmitter, presumably because its transmit button was stuck in the "on" position. As described in Appendix A, we input this entire interval into a digital computer, for subsequent detailed listening, viewing, and processing. This section describes the results of that examination. 3.1 The Unprocessed Waveform Data First, we made a high-resolution graphical plot of the waveform of this signal, at a scale of 5 in. per 1/10 sec, for detailed visual examination. The plot of the entire interval 22 63 comprises a roll of paper 12 in. wide by 234 ft long. Reductions of excerpts of this plot are reproduced in Fig. 4. In this figure and in the following discussion, time is noted in seconds from the beginning of the interval. The first region to be noted in Fig. 4 is the area around 131 sec. This region is typical of the high level of motorcycle noise that characterizes the first 2 minutes of the data. In the region of 132 to 133 sec, we can see the amplitude of the noise slowly drop. Later, when we discover the trajectory of the motorcycle as a by-product of detecting the sounds of shots, we find that the motorcycle was approaching the corner of Houston and Elm Sts. at this time. Therefore, this diminution of motorcycle noise is probably due to the slowing necessary to negotiate the 120(deg) left turn at the corner. At about 36.5 sec, we note a single large impulse of relatively long duration. Because of its length and because the region following this impulse is largely free of other impulses, such as the echoes normally associated with loud impulsive sounds, we feel that it is unlikely that this impulse represents the sound of gunfire. The regions around 137.3 to 138.7 and 139.2 to 140.9 sec are notable for a number of brief, loud impulses. These impulse patterns, the first to appear in the data up to this time, were judged as potentially representing gunfire. The region from 144.8 to 147.2 sec, which does not appear in Fig. 4, also contains a large number of impulses of similar character. Because this region is about twice as long as the 23 64 FIG. 4. WAVEFORMS RECORDED FROM CHANNEL 1 TRANSMITTER WITH STUCK MICROPHONE. 24 65 preceding ones. it was identified as possibly representing two separate impulse patterns, and, therefore, as potentially conraining the sounds of two shots. 3.2 Spectrographic Analysis Another way of portraying acoustical data is in the form of a spectrogram, in which the short-term spectrum of the signal is dispalyed as a function of time. Two example spectrograms from the region 141 to 148 sec are shown in Fig. 5. In this figure, time runs from left to right across the figure, and frequency from bottom to top. The energy at a given time and frequency is depicted by the blackness of the paper at that point. The region from 141 to 144 sec is only noise. Just after 144 see, a single loud click occurs, followed by a region of very faint speech (faint diagonal and horizontal smudges that change rapidly), clicks (thin vertical lines), and keying heterodynes (steady horizontal bars). The analysis into characteristic frequency components performed by the spectrograph permits us to recognize these events in a way not possible in the waveform patterns. 3.3 The Filtered Waveform Data To be sure that the 137- to 147-sec region of the transmission contained the only transients of potential importance with respect to gunfire, we attempted to remove the effect of the motorcycle engine noise to see if it was obscuring other transients. For this purpose, we implemented on a high-speed digital computer a noise-canceling filter program that adapts to and subsequently cancels sound components that appear to 25 66 FIG. 5. SPECTROGRAMS FROM WAVEFORM RECORDED FROM CHANNEL 1 TRANSMITTER WITH STICK MICROPHONE. 26 67 be non-random (in this case, the periodic noise of the engine). This filtering algorithm is described in Appendix A. It was tested on a high-fidelity recording of motorcycle engine noise and was found to be very effective in removing it. The adaptive filtering algorithm, when applied to the entire 5-minute segment of transmission, was not so effective. Figures 6 and 7 show the effect of filtering the waveform from 130 to 150 sec (overlapping the period for which the unprocessed waveform is shown in Fig. 4). The adaptive filtering removed hum and some low-frequency noise components, but the overall effect was not dramatic. Evidently, the distortions introduced by the radio transmitter, the original Dictabelt recording system, and the subsequent multiple playings of the Dictabelt had added nonrandom noise components that the adaptive filter was unable to remove. Appendix A also describes other signal-processing techniques that were applied to these data in attempts to remove the motorcycle noise and to detect and track motorcycle engine speed. The results in both cases were negative. 27 68 FIG. 6. ADAPTIVE FILTERED WAVEFORMS RECORDED FROM CHANNEL 1 TRANSMITTER WITH STUCK MICROPHONE (130 to 141 sec.) 28 69 FIG. 7. ADAPTIVE FILTERED WAVEFORMS RECORDED FROM CHANNEL 1 TRANSMITTER WITH STUCK MICROPHONE (141 to 150 sec). 29 70 4. SCREENING TESTS As described in Sec. 1, the four impulse patterns on the DPD tape were subjected to five simple but necessary screening tests. If the patterns did not pass any of these simple tests, then they could safely be assumed to have been caused by something Other than gunfire. If they were to pass these tests, they could not be assumed to be gunfire, but further analysis would be warranted. Essentially, the screening tests were designed to answer the following questions: l. Did the impulse patterns occur at the same time as the assassination? 2. Were the patterns unique? In other words, were they caused by the same source, and did they appear only at this time and nowhere else on the tape? 3. Did the time intervals between the impulse patterns match that of other evidence of gunfire? 4. Did the shape of the impulses resemble the shape of impulses of recorded gunfire? 5. Was the amplitude of the impulses similar to that of recorded gunfire? This section of the report describes how these questions were answered. 4.1 Time of Occurrence To determine the time Of day when the impulse patterns were recorded on Channel l, we examined the Channel l and the Channel 2 tapes. It is usual DPD practice for the Dispatchers on both channels to make frequent time annotations. In doing so, they 30 71 refer to two different clocks, which are synchronized at the beginning of each month and which are read out in full minutes only. An FBI study concluded that, towards the end of the month, the clocks could differ by as much as 1 minute. The allowable difference in the timing of events on Channels l and 2, therefore, was 60 sec. The Channel 1 segment was a continuous recording that had no time annotations during the period of stuck transmission, but time annotations preceded and followed this period. The Channel 2 segment was an intermittent recording with frequent time annotations throughout. A stopwatch was used to time the events on both channels. Figure 8 illustrates the results of stopwatch timing of the Gray Audograph record of Channel 2 events. Time annotations made by the Channel 2 Dispatcher are plotted against time on the stopwatch for the interval extending from 12:22 pm to 12:40 pm. Lines representing the least-square error fit are drawn through the time annotations. Note that the clock used by the Dispatcher is read out only in full minutes, and occasionally there is more than one annotation for the same minute. For the events occurring before 12:30 pm on the Channel 2 tape, the slope of the least-square error fit is only 0.4, indicating intermittent operation of the recorder, which stops recording when there are no Voice transmissions. At about 12:30 pm, the voice traffic picked up, and the Gray Audograph began recording continuously, as indicated by a least-square error fit slope of 1.0. 31 72 FIG. 8. LEAST -SQUARE ERROR FITS TO CHANNEL 2 DISPATCHER'S TIME ANNOTATIONS SHOWING TIMES OF DPD CHIEF'S RADIO TRANSMISSIONS. 32 73 The stopwatch time of two successive transmissions from Chief Curry are noted at the left of the illustration between the period extending from 6 minutes to 8 minutes. In the first, he notes that the motorcade is "approaching the triple underpass." After the Dispatcher notes the time as being 12:30, the Chief announces, "We are going to the hospital, officers." The assassination must have occurred sometime between Chief Curry's two voice transmissions. Since the slope of the least-square error fit changes at about 12:30, it is impossible to determine precisely the time on the Channel 2 clock when the assassination occurred. The best estimate is 12:30:12 pm. Figure 9 illustrates the results of stopwatch timing of the Dictabelt record of the events on Channel 1. Here, the slope of the least-square error fit is 0.95, indicating that the recorder was running 5% too slow and, therefore, was compressing time slightly.* The fact that the slope does not change over the course of the entire segment shows that the recorder operated continuously. The onset of the first impulse pattern, or gunfire-like event, on Channel 1 occurred at 12:30:47, Channel l time. Thus, the events on Channels l and 2 occurred within 35 sec of each other, well within the time difference allowable for this screening test. ------------------------------------- *Frequency analysis of the power hum on the tape recording also indicated that the recorder had been about 5% slow. Since the hum could have been added when the tape was recorded from the dictabels, this is not a reliable indication of the original recording speed. 74 FIG. 9. LEAST - SQUARE ERROR FIT TO CHANNEL 1 DISPATCHER'S TIME ANNOTATIONS SHOWING TIME OF FIRST SET OF GUNFIRE - LIKE EVENTS. 34 75 4.2 Uniqueness of the Impulse Patterns If impulse patterns similar to those occurring at the time of the assassination were to be found anywhere else during the 5-minute recording of stuck transmission, then the patterns could safely be assumed to have been caused by something other than gunfire. Thus, we examined processed waveforms for the entire segment of stuck transmission, looking for impulse patterns similar to those already identified. During the course of this examination, only one other pattern was found. It began about 30 sec after the other four patterns and was comprised mostly of impulses apparently caused by radios keying in, attempting to transmit. This sequence, which lasted for approximately 4 sec, did not resemble the earlier impulse patterns well enough to have been caused by the same source. 4.3 Time Span of the Impulse Patterns If the impulse patterns were caused by the gunfire of the assassination, the time span they occupy would have to be at least as long as the evidence of time between bullet impacts as seen on the Zapruder film. On that film, bullet impact is Judged to occur before frame 210 and again at frame 313, an interval of 103 frames. Since Zapruder's camera was judged to be operating at 18.3 frames per sec, the time span between these two events is 5.6 sec. The time span between the onset of the first impulse pattern and the onset of the fourth impulse pattern on the Channel 1 tape is 7.9 sec. When corrected for the fact that the tape recorder was running about 5% too slowly, the real time span is 8.3 sec, 76 FIG. 10. MUZZLE-BLAST AND SHOCK WAVEFORMS TRANSMITTED BY A POLICE RADIO SIMILAR TO THE ONE USED BY DPD MOTORCYCLES FOR SEVERAL DIFFERENT LOUDNESSES. 36 77 4.4 Shape of Impulses If the impulse patterns recorded on the DPD tape were gunfire, the shape of the waveforms would have been distorted by the limiting circuitry of the radio transmitter. Figure 10 shows the nature of these distortions. At the left of the figure is a muzzle-blast waveform obtained from the test firing of a Mannlicher-Carcano rifle. This waveform has a double peak showing the direct arrival of the muzzle blast with a strong ground reflection immediately following. A tape recording of these impulses was fed through a transmitting and recording system similar to that used by the DPD. The characteristics of both these systems are discussed in Appendix B. The series of five photographs of transmitted muzzle-blast waveforms shows the effect of the system's circuitry on impulse shapes --essentially, the louder the input signal, the greater the distortion. For example, the top photograph shows how the loudest signals, those arriving over the direct path, would be recorded. The signal that was input at 109 dB is a good example of what the reflection from a large and distant surface, such as the Post Office, would look like. Similar analysis of the shock-wave impulse at the right of the figure illustrates how the simple N-wave of the bullet is severely distorted when the input signal greatly exceeds the 100-dB limiting circuitry of the transmitter. Comparison of these waveforms with the impulse patterns obtained from the DPD tape showed sufficient similarity that the possiblity that the impulse patterns were caused by gunfire could not be ruled out. 37 78 4.5 Amplitude of Impulses Another characteristic of the waveforms that would have been affected by the circuitry of the radio transmitter if the input signal was as loud as gunfire was their amplitude. The recorded amplitudes of the sounds would be compressed in such a way that strong signals would appear to be weaker than they actually were, and weak signals in the same pattern would, therefore, appear stronger. As can be seen in Fig. il, this compression is greatest for very loud signals, especially those with high-frequency content. For example, although all the signals were compressed, the amplitude compression of muzzleblast waveforms above 100 dB was in every case less than that of the shock waves that are of higher frequency. When the peak-to-peak difference in amplitude between two signals was 30 dB, they were recorded as having only a 20-dB difference (muzzle blast) or only a 10-dB difference (shock wave). As the amplitude of the input signal decreased, the difference in peak-to-peak level became more noticeable. This analysis gave us greater insight into the characteristics of the sounds originally recorded on the DPD tape. The signals on that tape also appeared to be compressed in amplitude, indicating that the sounds, as originally picked up at the motorcycle microphone, may have been loud enough to have been caused by gunfire. 38 79 FIG. 11. LEVEL OF TRANSMITTED WAVEFORMS AS A FUNCTION OF WAVEFORM LEVEL AT THE MICROPHONE. 80 5. ACOUSTICAL RECONSTRUCTION IN DEALEY PLAZA Because the five screening tests described in Sec. 4 had failed to disprove the possibility of gunfire having been recorded on the Channel 1 tape, a more rigorous test was required. The objective of the acoustical reconstruction, therefore, was to obtain several "acoustical fingerprints" of the sound of gunfire in Dealey Plaza to compare with the impulse patterns found on the Channel l tape. If any of the "fingerprints" matched, then the reconstruction would result in determining both the timing of the shots and the locations of the weapon and the target for each shot. Only those weapon and target locations indicated by available testimony were to be tested. 5.1 Nature of the Test The most powerful test for the presence of weak signals that have many known features, but that are not clearly detectable because of background noise, is the correlation detection test. There are six distinct steps required to conduct this test. Step 1: Obtain acoustical measurements called test patterns, of the signals to be detected. These test patterns are uniquely determined by weapon- target-microphone locations for each shot. There were 12 combinations of weapon-target locations, and they are listed in Table T. There were 36 microphone locations (3 arrays of 12 microphones), which, along with the four target locations, are illustrated in Fig. 12. Thus, 432 (12 x 36) unique test patterns were obtained. Six of these are illustrated in Fig. 13, where the logarithm of sound-pressure amplitude is displayed as a function of time, on a scale 16 in. to 1 sec. 40 81 FIG. 12. MICROPHONE LOCATIONS AT DEALEY PLAZA. 82 FIG. 13. COMPARISON OF TEST ECHO PATTERNS PRODUCED BY BOTH WESTERN AND NORMA AMMUNITION FIRED FROM TSBD (MUZZLE WITHDRAWN) AT TARGET NO. 3 AND RECEIVED AT ARRAY 3, MICROPHONES 7, 8, AND 9. 83 TABLE I. SEQUENCE OF TEST SHOTS Weapon Location Target 1 Target 2 Target 3 Target 4 -------------------------------------------------------------------------- TSBD (Muzzle in plane of Shot 1 Shot 3 Shot 6 Shot 10 window) TSBD (Muzzle 2 ft inside Shot 2 Shot 4 Shot 7 Shot 11 plane of window) Knoll (Rifle) Shot 5 Shot 8 Shot 12 Knoll (Pistol) Shot 9 Step 2: Process the 432 unique test patterns into a like number of unique echo patterns or "fingerprints." Since the radio receiver compresses the amplitude of loud gunfire sounds into a narrow range of amplitudes, for comparison with the compressed impulse patterns, test-shot echoes that differ greatly in loudness must be compressed so as to differ only slightly in loudness after transmission by the radio. To achieve this compression, we selected only those echoes in a pattern having sufficient loudness to render them distinct from their neighboring weaker echoes. This echo selection process is illustrated in Figs. 14 through 17, for test patterns of individual shots as recorded by three adjacent microphones. For each of these figures, the geometry of the test shot -- i.e., the weapon-target microphone location sequence -- can be reconstructed by referring to Fig. 12. As can be seen from that figure, 12 microphones were placed in 3 successive arrays along the route of the motorcade, beginning at the right of the figure at the corner of Houston and Main. The outputs of the microphones were recorded on channels having the same numbers as the microphones. Thus, the echo patterns 84 in Fig. 14 represent the sound of gunfire made by a MannlicherCarcano rifle, withdrawn 2 ft within the plane of the TSBD window, fired at the target located closest to the TSBD, and picked up by microphones 4, 5, and 6 located on Houston St. before the turn onto Elm. In each of these four figures, 14 through 17, very loud echoes were selected from the echo patterns recorded by the three adjacent microphones. Those echoes Judged to have been caused by some feature in Dealey Plaza -- e.g., direct arrivals of shock wave and muzzle blast, ground and building reflections, etc. were identified by dots that are connected by nearly vertical lines. The reason the lines are not vertical is that the microphones were far enough apart to receive the same sound at dif ferent times. When Fig. 14 is again used as an example, the slope of the vertical lines at the left of the figure indicates that microphone 6 was closest to the weapon location and was, therefore, the first microphone to pick up sound arriving by the direct path and by other short paths. The slope of the lines at the right of the figure indicates that microphone 4 was closest to a major reflecting surface, such as the Post Office, and was the first to pick up those echoes. From the four groups of echo patterns shown in Figs. 14 through 17, we selected as "fingerprint" material the following number of echoes: 15, 14, 9, and 10. Again, selection of these echoes was based on their strength and on an understanding of how all the echoes would be compressed in amplitude by the limiting circuitry of the DPD dispatching system. The same procedure was used to select echo patterns from each of the 432 test patterns. Each echo pattern consisted of dots placed at 85 FIG. 14. ECHO PATTERN FOR SHOT 2 (TSBD, MUZZEL WITHDRAWN, TARGET NO. 1) RECEIVED AT ARRAY 2, MICROPHONES 4, 5, AND 6. 45 86 FIG. 15. ECHO PATTERN FOR SHOT 7 (TSBD, MUZZLE WITHDRAWN, TARGET NO. 3) RECEIVED AT ARRAY 2, MICROPHONES 4, 5, AND 6. 46 87 FIG. 16. ECHO PATTERN FOR SHOT 8 (KNOLL, TARGET NO. 3) RECEIVED AT ARRAY 3, MICROPHONES 4, 5, AND 6. 47 88 FIG. 17. ECHO PATTERN FOR SHOT 6 (TSBD, MUZZLE EXPOSED, TARGET NO. 3) RECEIVED AT ARRAY 3, MICROPHONES 4, 5, AND 6. 48 89 the time of each echo on a scale of 16 in. per sec, and there was an average number of 12 echoes on each echo pattern. Most echo patterns were of about l-sec duration, or 16 in. long. Step 3: Process into impulse patterns the segment of the tape recording that passed all five screening tests. The amplitude of the sounds on each segment was displayed in dB as a function of time, with each second of data occupying 16 in. of the display. The tape segment was subdivided for convenience into six separate segments of about 1-sec duration, each segment containing numerous sound impulses.* About 4 sec of data were discarded, because there were no impulses occurring within them. All impulses louder than a threshold value were selected as members of the impulse pattern. This process is illustrated in Fig. '18, where 17 impulses were selected in a 1.2-sec-long segment of the DPD tape that begins at 137 sec from onset of the stuck microphone. Above each numbered impulse in Fig. 18 is a pair of vertical lines separated from the time of impulse by 6 msec. The 12 msec between this pair of lines represents a window in which an echo from an echo pattern recorded during the reconstruction might acceptably occur. The reason for establishing such an acceptance window for the comparison between impulse and echo patterns is that the precise motorcycle position and, therefore, its position relative to the actual test microphone locations, was not known. This subject is addressed further in Sec. 5.2. Three other impulse patterns are illustrated in Figs. 19 through 21. These correspond to DPD tape segments that begin at 139, 145, and 145.5 sec, and they contain 15, 11, and 8 -------------------------------------------- *These segments included the four impulse patterns that passed the screening tests, with the fourth pattern divided into two segments, and one pattern that did not pass the tests. 90 FIG 18. IMPULSE PATTERN FROM STUCK-TRANSMITTER RECORDING BEGINNING AT TIME 137 SEC. 91 FIG 19. IMPULSE PATTERN FROM STUCK-TRANSMITTER RECORDING BEGINNING AT TIME 139 SEC. 92 FIG 20. IMPULSE PATTERN FROM STUCK-TRANSMITTER RECORDING BEGINNING AT TIME 145 SEC. 93 FIG 21. IMPULSE PATTERN FROM STUCK-TRANSMITTER RECORDING BEGINNING AT TIME 145.5 SEC. 94 impulses, respectively. The two impulse patterns not illustrated contained 4 and 8 impulses, so that all six of the l-sec segments averaged 10.5 impulses each. Step 4: Correlate each of the 432 echo patterns with each of the six impulse patterns for a total of 2592 separate correlation coefficients. The process of correlation, which obtains the measure of goodness of match between an echo pattern and an impulse pattern, is the essence of the correlation detector. The process is carried out by sliding the impulse pattern along the echo pattern until the maximum number of echoes occurs within the acceptable windows of corresponding impulses. This maximum number is called the number of matches. The correlation coefficient is the number of matches divided by the square root of the product of the number of echoes and the number of impulses; i.e., correlation coefficient If there is an equal number of echoes and impulses, and if they all match when the two patterns are positioned at one relative time, then the match is perfect and the value of the correlation coefficient is unity (1.0). If there are extraneous impulses or echoes, such as may be caused by noise on the DPD tape or by an echo-acceptance threshold too low for the reconstructed sounds, then the match cannot be perfect and the correlation coefficient will be less than unity. If the echo pattern is not at all similar to the impulse pattern, there will be only one or two matches. and the correlation coefficient will be only a little larger than zero. 95 The correlation coefficients for all 2592 matches were calculated by determining the maximum correlation coefficient possible for each, after sliding each pair of echo patterns and impulse patterns relative to one another. The time of the first impulse on the impulse pattern was noted with respect to the instant that the microphone button became stuck. Step 5: Select all correlation coefficients having values greater than the detection threshold value. The detection threshold concept is necessary because we have observed that noise and experimental uncertainty tend to prevent any perfect correlations (unity value of the correlation coefficient). Whenever an echo pattern matches sufficiently well with an impulse pattern to produce a correlation coefficient higher than the threshold value, that echo pattern is said to pass the detection test. There are two possible meanings to be assigned to each passing of the test. First, if the impulse pattern was truly caused by gunfire, the passing is called a detection. Second, if the impulse pattern was not caused by gunfire -- but rather by any other event capable of introducing noise in the radio -- then the passing is called a false alarm. Since impulse patterns that are truly caused by gunfire and mixed with radio noise cannot be expected to correlate perfectly with the test patterns, the detection threshold must be set low enough to ensure that no detections are missed. But the lower the detection threshold is set, the more false alarms that can be expected to occur. The analysis described in Appendix C indicated that random noise on one l-sec segment of the DPD tape having about 12 impulses per sec will cause 55 96 fewer than 3.3 false alarms out of 432 echo patterns, provided the detection threshold is 0.6. This rate of false alarms was Judged acceptable and was considered necessary to prevent misses. Step 6: Eliminate from the set of detections and false alarms the false alarms that can be identified. Since false alarms are caused by noise (unexplainable events), they may occur with echo patterns that represent weapon, target, and microphone positions that are obviously disjoint from actual detections and from false alarms that mimic actual detections. These events can be correctly identified as false alarms and eliminated from further consideration. Only independent (non-DPD tape) evidence can be used to identify those false alarms that may be mimicking detections. 5.2 Problems To Be Solved by the Acoustical Reconstruction Test The acoustical reconstruction test had to be conducted in a safe and timely manner. Therefore, all conceivable weapon, target, and microphone locations could not be reconstructed. Five problems arising from this fact, and their solutions, are discussed here. 1. Where in the motorcade was the motorcycle during the time span of the assassination, assuming that it was in the motorcade? The motorcycle would need to be within the confines of Dealey Plaza in order to pick up the sound of gunfire, From the corner of Main St. and Houston St. to the position of the President's limousine at the time the President's head wound was inflicted is a distance of about 460 ft. Since the pavement 56 97 widens greatly at the corner of Houston and Elm, about 150 ft needed to be covered twice, for a total linear distance of 610 ft. It was judged that there would be time from sunrise until noon to conduct four complete firing sequences. One of these would need to be a repeat to test for the similarity of two types of ammunition. Only 12 microphones could be used simultaneously, because of the need to keep 2 channels of a 14-channel tape recorder in reserve for annotation. Therefore, 36 microphone positions would have to cover a distance of 610 ft. Also, the streets in Dealey Plaza are about 40 ft wide, meaning that a motorcycle would likely be no more than about 18 ft from the center of a street. For these reasons, the microphones were spaced 18 ft apart, as illustrated in Fig. 12. Because of the spacing of the microphones and lack of knowledge of the precise position of the motorcycle within the motorcade, it was Judged that the motorcycle would, in the worst case, have been no more than 18 ft away from a microphone location. The most likely separations were accounted for in Sec. 5.1, Step 3, by the establishing of a -+6-msec acceptance window for matching echo and impulse patterns. 2. Is live ammunition necessary in the acoustical reconstruction, and does the type of weapon and ammunition make a difference? In Sec. 2, we described how the shock waves generated by rifle bullets would be sufficiently loud at some microphone positions to become a significant part of an echo pattern. The speed of the bullet is important, because it determines the difference in time between perception of the shock waves and perception of the muzzle-blast waves. Therefore, it would 57 98 be best to use the same type of rifle and the same type of ammunition in the reconstruction as was used in the assassination. Evidence dictated use of a Mannlicher-Carcano rifle from the sixth floor of the TSBD, firing Western Cartridge Co. ammunition. The Committee supplied a similar rifle, but only 15 WCC rounds. It was necessary to use Norma ammunition for the first three sequences of rifle fire, while the fourth sequence was a duplicate of the third, with the exception of substituting WCC rounds for Norma rounds. No significant difference due to the type of ammunition was observed, as can be seen in Fig. 13. Gunfire from behind the fence on the knoll had been alleged by some, although there was no evidence to indicate what type of weapon or ammunition might have been used. The greatest difference between echo patterns caused by two different weapons occurs whenever one fires a supersonic projectile and the other a subsonic one. For this reason, a Mannlicher-Carcano was used to produce the supersonic projectile and a 38-caliber pistol was used to produce the subsonic projectile. Since the knoll-to-target distances were only about lOO ft, it was not necessary to obtain great accuracy in matching test weapons with alleged assassination weapons in this case. 3. Where should the targets be located? Photographic evidence indicated that shots struck the President when his limousine was at the locations indicated approximately in Zapruder frames 200 and 313. Also, evidence indicated that a bullet may have struck the curb on the south side of Main St., near the triple underpass. Finally, our initial investigation of the tape indicated a shot may 58 99 have been fired when the limousine was near frame 160. For these reasons, four targets were selected, and their positions are marked on Fig. 12. 4. Had any significant physical changes been made in Dealey Plaza? An important factor to be considered was the change over 15 years in the physical, and therefore acoustical, characteristics of Dealey Plaza. The absence of the crowd and cars was Judged insignificant, because reflections of sound from these sources would constitute sufficiently weaker signals than those that would be selected for analysis. Thus, only two changes of importance had taken place: the introduction of the Hyatt Regency building a couple of blocks away as a possible reflector of sound and the absence of the building formerly located at the southeast corner of Commerce and Houston Sts. Travel time for a sound wave to reach the Hyatt Regency and be reflected back to the microphone was estimated at 2 sec. Since the four impulse patterns had durations of no more than 1.1 sec each, the echo from the Hyatt Regency would not distort the data. The sound waves that originally hit the missing building would have been diffracted by the corner of the building itself, with much of the sound energy being scattered. The reflected signal from this building would, therefore, have been sufficiently weak to have been swamped by the very strong reflection coming off the Post Office Building located at the southwest corner of the same streets. 59 100 For the purposes of reconstruction, therefore, Dealey Plaza was judged to have the same acoustical characteristics in 1978 that it had in 1963. However, when the test was being set we found that to shoot from the TSBD at Target No. 2, it was necessary to shoot between two overhead signboards on a sign above Elm St. that was not there during the assassination. This sign could not be moved. The secondary echoes generated by the projectile shock waves impinging on these two signs apparently reduced the correlation coefficients for matches with test shots at this target, for only three were ever found to exceed the detection threshold, and these were identified as false alarms. 5. How could the listening tests be accommodated? The experts used by Dr. Green* to determine how earwitness accounts of the sounds of gunfire might be explained needed to hear each of the various test shots from at least four different locations. This requirement was met by our use of four identical sequences of test shots. 5.3 Results of the Acoustical Reconstruction Test Of the 2592 maximum correlation coefficients determined by correlating the 432 echo patterns with the impulse patterns on six tape segments, 15 correlation coefficients exceeded the detection threshold value of 0.6. The time and weapon-target microphone locations for each of these coefficients are listed in Table II. Inspection of the table shows that no correlations exceeded the threshold value for the two segments beginning at 136.20 sec and 146.30 sec after the time the microphone button became stuck. Fourteen of the 15 correlations that did exceed the -------------------------------------- *See footnote, p. iv. 101 TABLE II. LIST OF ALL 15 CORRELATIONS BETWEEN IMPULSE PATTERNS OCCURRING IN SIX SEGMENTS OF THE DPD RECORD AND ECHO PATTERNS FROM 432 TEST SHOTS (2592 SEPARATE CORRELA- TIONS) HAVING A CORRELATION COEFFICIENT HIGHER THAN 0.5. 102 threshold value occurred at four different instants of time, those beginning at 137.70 sec, 139.27 sec, 145.15 sec, and 145.51 sec. This result shows the possibility of four shots having been fired, each at One of the four times listed. The fifteenth correlation value to exceed the detection threshold occurred at 140.32 sec after the time the microphone button became stuck. This lone correlation will be identified as a false alarm in the next section and, therefore, does not indicate the possibility of a fifth shot. These times are all about too small, because the tape-recording process was found to be about 5% slow (see Sec. 4.1). 5.4 Conclusions about the Acoustical Reconstruction Test It becomes clear upon examination of the weapon, target, and microphone locations for the several echo patterns that passed the correlation detection test at each of the four different times, that some are inconsistent with each other. Thus, some or perhaps all represent false alarms. Deciding which are false alarms was greatly facilitated by plotting the microphone locations for each of the 15 echo patterns against the time on the DPD tape when it correlated highly. This plot appears in Fig. 22, where zero on the time scale is taken to be the time on the DPD tape where high correlations were first detected. Zero on the distance scale is taken at the point where the Hughes film(1 )shows a motorcycle to be, just as the Presidential ------------------------------------- *Frames from the film taken by Robert Hughes, an amateur photographer, were introduced as evidence at the December 29 Hearing. This film was taken from the left-hand edge of Houston St., near Main St. With the camera pointed north up Houston St., the limousine is seen Just disappearing around the corner after a left turn onto Elm St. A few frames later a motorcycle passes through the field of view, moving from right to left, proceeding north on Houston St. 62 103 FIG. 22. MICROPHONE POSITIONS ALONG MOTORCYCLE ROUTE WHERE HIGH CORRELATIONS WERE OBTAINED, AS A FUNCTION OF TIME. ESTIMATED TRAJECTORIES OF MOTORCYCLE AND OF THE PRESIDENTIAL LIMOUSINE ARE SHOWN FROM THEIR POSITIONS INDICATED BY THE HUGHES FILM AT THE TIME THE LIMOSINE TURNED DOWN ELM ST. 63 104 limousine is seen to disappear around the corner from Houston St. onto Elm St. This motorcycle position is marked M in Fig. 12. Distance is measured in feet from this point along the motorcade route. Even a brief glance at Fig. 22 shows that the microphone locations that correspond to correlations at the three times after the first impulse tend to progress uniformly forward along the motorcade route. This conclusion can be quantified statistically by the chi-square test. If the motorcycle were not moving through Dealey Plaza at the time of the assassination, the distance along the motorcade route would be a meaningless coordinate, and the microphone locations for the correlations that exceed the detection threshold would occur at random. When the chart in Fig. 22 is partitioned into a 2 x 2 table by separating time at 5 sec and distance at 250 ft, we find l, 6, 8, and 0 correlations in the four sections reading from left to right, top to bottom. But the expected number of correlations to be found in these four sections, if the correlations occurred at random, are 4.2, 2.8, 4.8, 3.2. The value of chi-square for the observed and expected values is equal to 11.4. There is only 1 degree of freedom in this 2 x 2 table, and the probability that this large value of chi-square could occur at random is less than 1%. Therefore, there is little doubt that the distance coordinate is meaningful, and we conclude that the motorcycle was moving through Dealey Plaza and did, in fact, detect the sounds of gunfire. Looking at the information in Table II and in Fig. 22, we can determine that at least 6 of the 15 correlations above the detection thresholds are false alarms. These six false alarms are indicated in Fig. 22 with an X drawn over them, and they are: 64 105 l. The fourth entry in Table II that occurred at 137.70 sec is a false alarm, because it represents a rifle shot fired from the knoll at Target 4 near the triple underpass at a time when the limousine was near the position seen in frame 171. Thus, this shot was fired in a direction opposite to that of the logical target. 2. The entry in Table II that occurred at 140.32 sec is a false alarm, because it occurred only 1.05 sec later than earlier correlations also obtained from the TSBD. The rifle cannot be fired that rapidly. Since there are three correlations plausibly indicating the earlier shot, the one occurring 1.05 sec later must be a false alarm. 3. The fourth entry in Table II that occurred at 139.27 sec is a false alarm, because the motorcycle would have had to travel 130 ft in 1.6 sec (55 mph) to gain that position. 4,5,6. The second and third entries at 145.15 sec and the third entry at 145.61 sec are false alarms, because the motorcycle would have had to travel at 16 mph to gain the indicated position of only 70 ft behind the limousine at the time of the last shot. The motorcycle noise level (see Fig. 4) decreased by about 10 dB Just 3 sec before the time of the first correlations, indicating a slowing to negotiate the 120 deg. turn onto Elm St. The motorcycle noise level did not increase for the next 13 sec, so it could not have increased speed to 16 mph and maintained it. 65 106 There remain nine correlations that exceeded the detection threshold, and they occur at four different times: Group 1. 137.70 sec -- four correlations with test shots from the TSBD at Targets 1 and 3.* Group 2. 139.27 sec --three correlations with test shots from the TSBD at Target 3. Group 3. 145.15 sec -- one correlation with a test shot from the knoll at Target 3. Group 4. 145.61 sec -- two correlations with test shots from the TSBD at Targets 3 and 4. There is no other acoustical evidence that would help to determine which of the remaining nine correlations are false alarms, if any. Clearly, at least one of the first two groups of correlations and at least one of the second two groups of correlations must contain detections, because the order found in the data would not likely have occurred by chance. The probability that two detections have been achieved and that one is near 138 sec and the other near 145 sec is at least 95%. However, the expected number of false alarms to be found when testing four different impulse patterns is 13 (see Appendix C), and only six have been found. Therefore, it is not unreasonable to expect that there are seven more, although that would be the largest number possible since at least two of the remaining nine are probably detections. The best that can be safely assumed is that each of the nine remaining correlations is equally likely to represent a detection or a false alarm. --------------------------------------- *Possibly because of the presence of an overhead sign that Enterfered with test shots at Target 2, no correlations were found with that target. 66 66 107 On the basis of this judgment and the assumption that each of the 15 events are independent, the probabilities of several different Outcomes can be calculated. The probability that at least two shots have been detected is 96%, the probability that at least three shots have been detected is 75%, and the probability that four shots have been detected is 29%. The individual probabilities that shots occurred at each of the four times at which correlations exceeded threshold are 88%, 88%, 50%, and 75%, listed in order of increasing time. The combined probability that there were three shots and that the third (knoll) shot was one of them is 47%. Our correlation detector that located the origin of gunfire also located the position of the radio that transmitted the gunfire sounds. It is important to show that the motorcycle trajectory determined by the detections is compatible with independent evidence about a motorcycle trajectory. The necessary independent evidence to show this compatibility is partially obtained from the positions of the Presidential limousine and a motorcycle shown in the movie taken by Hughes (see footnote on p. 62). This movie shows the limousine just turning Onto Elm St. just before a motorcycle passes that has turned onto Houston St. from Main St. We estimate that the motorcycle was at point M (Fig. 12) at that sighting. We estimate that the limousine was at the position of microphone 2(9) (Fig. 12) at that sighting, 215 ft north on Houston St. The position of the limousine at the instant of the President's head wound is shown in Fig. 22 at two different times, assuming that either the third or the fourth shot 67 108 struck. Photogrammetric determination of the limousine speed on Elm St. was about 11 mph. The limousine's positions at times before the head wound is shown by the two parallel lines proJected backward, having a slope equal to 11 mph. The two times at which the limousine position is equal to its assumed position when the motorcycle was at point M are shown in Fig. 22. We find that these times were either 6.5 sec or 7.2 sec before the first shot was fired. The motorcycle position at either one of these two times was 180 ft away from its position when the first shot was fired, according to the results of our correlation detector. Therefore, its average speed north On Houston St. would be either 15.9 mph or 18.6 mph, depending upon whether the third or fourth shot caused the head wound. These two trajectories are shown in Fig. 22 also. A precise motorcycle location at the time of the third shot, calculated by Weiss and Aschkenasy, was found to be 5 ft southwest of microphone position 3(4). This location is marked in Fig. 22. The straight line that passes through this point, and best fits the eight other microphone locations that produced echo patterns indicating the other three shots, plotted in Fig. 22. This line is the estimated motorcycle trajectory on Elm St., and it indicates an average speed of 10.6 mph. The complete motorcycle trajectory shows that the motorcycle traveled north on Houston St. at about 17 mph. It slowed to about 10 mph at a point about 40 ft south of the corner at Elm St., and then continued west on Elm St. at about 10 mph. This single diminution of speed is compatible with the single 68 109 diminution of motorcycle noise about 3 sec before the first shot is heard (see Fig. 6). We conclude that the motorcycle trajectory determined by the gunfire detections is compatible both with the positions of a motorcycle shown in the Hughes film and With the loudness of the motorcycle noise as transmitted to the Dispatcher. 69 110 6. ADDITIONAL RELEVANT SOUNDS ON THE DPD CHANNEL 1 TAPE In an attempt to gain as much acoustical evidence as possible, the Channel l tape was examined for other relevant sounds. These other sounds consisted primarily of the tolling of a bell, the noise of sirens, and voice and other transmissions. 6.1 Bell The toll of a bell can be heard faintly at about 152.5 sec. It was hoped that the location of the bell, and therefore of the radio transmitter, could be obtained by acoustically identifying the bell. The energy spectrum of the 1/3-sec segment containing the bell sound is shown in Fig. 23. Several peaks evident in the spectrum are harmonically related. The fundamental frequency of this series of spectral peaks is 210 Hz. The spectral peaks are marked according to the usual nomenclature used to describe overtones of a carillon bell. The fundamental tone is called the hum note. The second harmonic, called the strike note, is at the nominal pitch of the bell -- in this case, 420 Hz. The third harmonic is a fifth above the strike note. Higher harmonics are strong at 1050 Hz and 1470 Hz. The minor third above the strike note is strong, and this fact is characteristic of carillon bells. The tape-recording system was found to be about 5% slow, when the time annotations were measured with a stopwatch (see Fig. 9). Therefore, the apparent pitch of the tone would have a frequency of (1.05) (420) = 441 Hz. 70 111 FIG. 23. ENERGY SPECTRUM OF TAPE SEGMENT CONTAINING THE SOUND OF A BELL. 71 112 Careful investigation by the Committee staff did not discover any such bell within earshot of Dealey Plaza. During the acoustical reconstruction tests in Dealey Plaza, the sounds of railroad locomotive bells were recorded and subsequently analyzed. These sounds bore no similarity to the carillon-like sounds of the original recording. We concluded that the bell sound on the Channel 1 tape recording must contain sounds from at least one transmitter not in Dealey Plaza at a time near 152.5 sec. 6.2 Sirens The region from 263 to 300 sec of the stuck transmission contains the sounds of a number of sirens. The effect is not that of a microphone being carried on a vehicle with a wailing siren, but rather of many vehicles with sirens coming and going around the microphone. 6.3 Voice and Other Remote Transmissions Starting just after 264 sec, a voice transmission says, "Anybody know where 56 is?" The quality of this voice is such that it sounds as if it may have been picked up by the open microphone of the stuck transmitter, rather than having come from a second transmitter on the same channel, but it is impossible to tell for sure. In many other cases, there are brief voice signals from other remote transmitters. Sometimes these signals are too faint to be understood (such as the voice signal shown in the spectrograms in Fig. 5), sometimes they are loud but very distorted, and sometimes they are quite intelligible. These 72 113 competing transmissions are often, but not always, accompanied by heterodynes, which are tones caused by slight differences in frequency among the competing transmitters. Many times these remote transmissions are very brief (around O.l sec) "beeps" with no voice, signifying attempts to make one's desire to use the channel known. This beeping is common practice on a shared radio channel. 73 114 7. REVIEW OF AN INDEPENDENT ANALYSIS OF THE POSSIBLE THIRD SHOT Owing to the uncertainty about the possible third shot found in our study, the Committee sought an independent analysis. Professor Mark Weiss and Mr. Ernest Aschkenasy of Queens College conceived of an analytical extension to our work that could determine with more certainty whether or not the match between one echo pattern from our acoustical reconstruction with one impulse pattern on the DPD tape indicated a third shot. At a meeting on October 24, we contributed to the design of this analytical work. Their analysis was conducted as follows. First, they made a graph of the waveform of the echo pattern we recorded on microphone 3(4), when a rifle was fired from the knoll at target no. 3 (see Table II). From this graph, they identified the 22 loudest individual echoes within the pattern. Then, they identified the 22 echo-producing objects within Dealey Plaza by noting which objects corresponded to observed echo delay times - i.e., by identifying rifle-to-object-to-microphone sound paths that would account for the times each of the 22 echoes were received by microphone 3(4). Next, they analytically moved the position of microphone 3(4) several times by calculating for each time what the echo pattern would have looked like if that microphone used in the acoustical reconstruction had been located in these other positions. After a time, they found that a position about 5 ft southwest of the actual location of microphone 3(4) represented the true location of the motorcycle at the instant the muzzle blast would have been received by its radio. Then they calculated the delay times for each of the 22 echoes received at 74 115 that point as it moved down Elm St. at 11 mph. The resulting series of echoes was found to match with the sound impulses on the DPD tape beginning at about 144.9 sec (see Table II). Weiss and Aschkenasy found that 12 Of the 22 echoes were loud enough to exceed a threshold that they felt excluded most of the weak echoes that would not be audible in the DPD tape. They found that 10 of these 12 echoes occurred within -+1 msec of the occurrences of 10 of the 14 impulses on the DPD tape that were loud enough to exceed a threshold. The value of the correlation coefficient that represents this match is 0.77. This value exceeds the threshold value of 0.60 for which we accept a correlation as possibly indicating a shot. The probability that a false alarm will be produced by the correlation scheme used by Weiss and Aschkenasy is much lower than it is by our correlation scheme, because in our analysis we counted echoes that occurred within +/- 6 msec of the occurrence of impulses on the DPD tape. We were required to count echoes occurring within this larger time interval, because of our initial uncertainty of the true motorcycle location. We computed the probability that Weiss and Aschkenasy could have obtained by chance their good match between their calculated echo pattern and the impulse pattern on the DPD tape. We observed that they obtained 10 matches, to a precision of +/- 1 msec, out of 12 test echoes, with 14 impulses in a 320 msec time span. We note, however, that the 12 test echoes were contained in two time intervals of 90-msec total duration. These two intervals were separated by a span of about 230 msec in which no echoes appeared. Because an echo was counted if 75 116 it occurred within a 2-msec time window, there were 45 possible windows in which echoes may occur. Since one of the 10 occurrences can always be matched simply by adjusting the origin of the time scale, there are only 9 independent occurrences. The probability of obtaining by chance 9 or more out of 12 echoes occurring within any specific 14 time windows out of a possible 45 is equal to 3.13x10(')-4. This probability of obtaining by chance as good a match as was obtained on a single try is given by the hypergeometric probability function. However, they were required to try not once, but about 180 times. This is because the motorcycle could have been anywhere in a 40-ft by 18-ft rectangular space. Since a significantly different pattern would be calculated by them for each different 2-ft by 2-ft square, they were required to examine about 180 different patterns. The probability of obtaining )Just one match by chance in any of 180 independent tries is equal to 5.3x10(')-2, or about 5%. Therefore, the probability that they obtained their match because the two matched patterns were due to the same source (gunfire from the knoll) is about 95%. 76 117 APPENDIX A. COMPUTER SIGNAL PROCESSING Many of the analyses of the acoustic data were performed on digital computers. In this appendix, we describe these processing methods. A.I Digitizing When played from a magnetic tape, sound is in the form of a continuous electrical signal. For it to be amenable to processing by a digital computer, its voltage must be sampled, or read, at frequent intervals. The voltage must then be expressed as a digital quantity. The sampling rate must be sufficiently rapid to preserve the high-frequency components of the signal; sampling rates of 10,000 times per sec and 20,000 times per sec were used in this work. The signal must then be digitized with an analog-to-digital converter; the resulting series of numbers is stored on a computer diskfile. A.2 Interactive Playback and Display Once the signals have been digitized, waveforms can be graphically plotted on a computer display; the signals may also be reconverted to sound by a digital-to-analog converter. Interactive signal display, editing, and playback programs make it possible to display any time interval of the signal and to convert it back to a sound signal for listening. This interactive process of observing portions of the signal waveform and simultaneously listening to it is very valuable. A-1 118 A.3 Plotting In addition to showing portions of the signal waveform on the computer display, we also used the computer and a graphical plotter to make pen-and-paper drawings of the signal waveforms. These high resolution plots, usually made with a scale of 5 in. per 1/10 sec, provide a permanent record of the signal. Examples of these plots are shown in Sec. 3 of this report. A.4 Signal Enhancement Computations performed on the digitized signal can produce filtered versions and other representations of the signals. Digital signal processing can accomplish the same kinds of filtering that can be performed in the analog domain, and it can accomplish new kinds of filtering that are impossible by conventional means. Several different kinds of signal processing were performed on the data. Enhancement by Adaptive Noise-Cancelling Filter An adaptive noise-cancelling filter differs from fixed filters in that it automatically adjusts its signal-processing characteristics by means of an algorithm that allows it to predict certain noise components. The particular filtering process* used for the Channel 1 tape allows the filter to separate periodic components of the noise from random components. Periodic components are those elements of an input signal that repeat at regular intervals -- for example, the ticks of a clock and a 60-Hz powerline voltage hum. -------------------------------------- *Widrow, B., Glover, J.R., Jr., McCool, J.M., Kaunitz, J., Williams, C.S., Hearn, R.H., Zeidler, J.R., Dong, E., Jr., and Goodlin, R.C., "Adaptive Noise Cancelling: Principles and Applications," Proc. IEEE 63, 1692-1716 (December 1975). A-2 119 One property of periodic components is that, given sufficient past history, they can be predicted; indeed, a perfectly periodic signal can be predicted perfectly. The filter "learns" from the past history of the signal, estimates the signal for the next time period, and subtracts its estimate from the input. What is left are those portions of the signal that the filter cannot estimate -- i.e., the random components. A time delay was inserted into the processing system, Just ahead of the adaptive filter, to assist in controlling the separation of periodic and random components. Random components having time duration less than that of the time delay pass through essentially unaffected by the filter. These random components form the primary output of the filter. A second output was the periodic component that was being subtracted out; this subtracted information was also saved in digital form on disk. Examination of this subtracted signal, by aural and visual means, yields considerable insight into filter performance. Several test signals were fed into the filter to verify proper operation and to adjust the various filter parameters. The filter performed very well on the various test signals. On the DPD Channel 1 tape, anticipated periodic and undesirable interferences included components of motorcycle cylinder firing, powerline hum, heterodyne "squeals.," and occasional speech. Sections of this tape were played into the filter with a wide range of filter parameter values. Filter action was monitored by listening to both the primary and the secondary outputs. The filter removed residual powerline hum, some speech, and heterodyne "squeals" of time duration longer than that of the time delay. However, it A-3 120 accomplished little with respect to what had been believed to be motorcycle noise. We therefore performed an autocorrelation analysis, as described below. Autocorrelation Analysis of Motorcycle Engine Noise Our interpretation of the sounds on the Channel 1 tape would have been made much easier if we had had some knowledge of the movements of the motorcycle carrying the microphone. For example, if we had had information on when the motorcycle was moving steadily (along a straight street), slowing down and possibly shifting gears to turn a corner, or stopping, we might have been able to infer whether these movements were consistent with travel into or through Dealy Plaza. However, we did not have this information. Thus, to determine the engine speed with greater accuracy than is possible from engine loudness, we wrote a computer program that would compute the short time autocorrelation function of the motorcycle noise signal. This function assesses the similarity of a signal with itself shifted in time; if the signal is periodic, this similarity will peak when the signal is shifted by one period. This autocorrelation analysis program was applied to the stuck transmission period on the Channel 1 tape. The results showed no periodicity that we could attribute to motorcycle engine firing. As a test case, this program was also applied to a high-fidelity recording of motorcycle engine noise, and it clearly showed the known periodicity of the test signal. Although our failure to detect the motorcycle engine periodicity is puzzling, it is consistent with our inability to perceive the engine firing clearly when we are listening to the tape, and it is also somewhat consistent with the failure of the adaptive noise-canceling filter to filter out a coherent motorcycle engine sound signal. A-4 121 Enhancement by Spectral Subtraction A third method applied to enhance the Channel 1 signals was the subtraction of a noise spectrum estimate. This method is currently under development at BBN, under U.S. Government sponsorship, for the enhancement of speech signals in the presence of stationary flat-spectrum additive noise.* It is similar to, but somewhat more general than, the INTEL enhancement method developed by Weiss et at We could not tell whether this method would be effective with nonstationary non-flatspectrum noise, but since the program was already available, we tried it. In this method, the signal is converted by a Discrete Fourier Transform to a magnitude spectrum and a phase spectrum. A previously computed estimated noise spectrum is subtracted from the magnitude spectrum; the altered magnitude spectrum is then recombined with the phase spectrum converted back to a waveform by an Inverse Discrete Fourier Transform. Several parameter settings for this filtering method were used with a portion of the Channel 1 tape. None were successful in reducing the motorcycle noise without introducing noise transients attributable to the filtering process. ----------------------------------- *Berouti, M., Schwartz, R., and Makhoul, J., "Enhancement of Speech Corrupted by Acoustic Noise," IEEE Int. Conf. on Acoustics, Speech, and Signal Processing, Washington, DC, April 2-4, 1979. +Weiss, M.R., Aschkenasy, E., and Parsons, T.W., "Study and Development of the INTEL Technique for Improving Speech Intelligibility," Nicelet Scientific Corp., Report RADC-TR75-108, 1975. A-5 122 APPENDIX B. RADIO TRANSMISSION OF GUNFIRE SIGNALS The 1963 DPD Channel 1 radio link and recording system contained the following components: microphones, radio transmitters, an RCA Fleetline radio receiver (Model C9F350), and a Dictabelt recorder. Radio systems such as this are designed to carry speech signals and therefore incorporate signal modifiers to optimize the dynamic range and bandwidth of the system with respect to voice transmissions. Since these signal modifiers are usually incorporated in the transmitter, rather than in the receiver or the recording device, we focused our efforts to simulate the radio link on the transmitter/microphone combination. Among the radio transmitters in use by the DPD in 1963, House Committee researchers found that five different models were used on motorcycles. These were * Motorola Model FMT-41 * Motorola Model T-31BAT * Motorola Model U-41GGT * Motorola Model T-41GGT * General Electric Model MT-13-N. At the time of this study, it was very difficult to find manuals for these models and even more difficult to obtain access to a working unit. With the manuals-we were able to find and with assistance from Motorola factory personnel, we discovered that the microphone used with the T-31BAT would have been Motorola NMN 6006A and that microphones used with the Other Motorola transmitters would have had similar B-1 123 characteristics; i.e., they would have been dynamic cardioid types with internal preamplifiers. We have no information about the GE radio model and its microphone. We eventually located a T-3lBAT owned by the Boston Metropolitan District Commission Police Department. The MDC kindly made this radio and a GE Model ERSlA receiver available to us. The basic scheme used in this and other Motorola radio transmitter/microphone systems of the same vintage is sketched below. This type of circuit limits the slope of the audio DIAGRAM signal rather than its amplitude. Therefore, it will limit highfrequency signals more than low-frequency signals, as shown in Fig. 11 of this report. The frequency response of the system rolls off at 36 dB/octave above 3 kHz and at 6 dB/octave below 2.3 kHz. The signal, in effect, is differentiated and low-pass filtered. The smoothed, calculated frequency response of the system is plotted in Fig. B.1. Our procedure for obtaining the data shown in Figs. 10 and 11 was to play tape recordings of gunfire, made anechoic by time gating, through a circuit designed to simulate the frequency response and amplitude-limiting characteristics of the Motorola 6006A microphone into a second tape recorder. We then took the second tape to the MDC Police radio shop. There, we played this tape through a variable attenuator (to control the level of the signal being put into the transmitter), through the Motorola B-2 124 FIG. B.1 TRANSMITTER/MICROPHONE SYSTEMS FREQUENCY RESPONSE. B-3 125 transmitter, through the GE receiver, and onto another tape recorder. This third tape recording was played back into an oscilloscope and photographed producing the waveforms shown in Fig. 10. Peak-to-peak amplitudes of these waveforms were measured and plotted to produce Fig. 11. In addition to having had similar effects on the waveforms recorded on Channel 1, the DPD recording shows evidence of a time constant in the O.1 to 1.0 sec range. This AGC does not occur in any of the Motorola transmitters. It could, therefore, have been caused by the GE transmitter, by the receiver, or by the recorder. B-4 126 APPENDIX C. ANALYSIS OF FALSE ALARMS IN THE CORRELATION DETECTION TEST The process of binary correlation that was used to detect gunfire echo patterns among the impulse patterns on the DPD tape can, like any other detector, produce false alarms. This analysis determines the number of false alarms to be expected from random noise impulses on the DPD tape. Each echo pattern contains an average of M = 12 echoes in a 1/2-sec span. But, we consider each echo to have a +/- 6-msec acceptance window to account for echo time differences introduced by not knowing the motorcycle position relative to the test microphone positions. Therefore, there are about N = 40 different time slots in which the 12 echoes may exist. Each impulse pattern contains some number of impulses ranging from n = 8 to n = 17, also in a 1/2-sec span. The matching process seeks to find the number of impulses, that lie within the acceptance windows of the echoes that comprise the echo pattern. If the impulses are caused by a random noise source, then the number of matches, i, is what would be expected from random sampling n times a population of N that contains M echoes. The probability of getting I matches at random is given by the hypergeometric probability distribution p(N, M, n, i). The correlation coefficient is defined to be equal to i/mn. The probability of obtaining a correlation coefficient equal to 0.6 or greater was calculated for N = 40, M = 12, and n = 8, 10, 12, 13, 14, 17. The results for the six successive values of n were: 4.8x10-3, 6.0x10(-3), 8.5x10(-3), 1.0x10(-2), 1.2x10(-2), 1.5x10(-2). C-1 127 For an impulse pattern having 10 impulses (n=10), there are expected (6.0x10-3x432) = 2.6 false alarms, because there ave 432 echo patterns to correlate with. There were four impulse patterns that were correlated with all 432 echo patterns, and they had n = 8, 10, 12, 17 impulses on them. The total number of false alarms to be expected works out to 13. This number was Judged to be acceptably small, so the detection threshold value was set at 0.6. C-2 128 Report No. 4034 Analysis of Earwitness Reports Relating to the Assassination of President John F. Kennedy D.M. Green January 1979 Prepared for: Select Committee on Assassinations Bolt Beranek and Newman Inc. 50 Moulton Street Cambridge, MA 02138 129 TABLE OF CONTENTS page LIST OF FIGURES AND TABLES iv SECTION 1. INTRODUCTION....................................1 2. LOCALIZATION OF SOUND...........................2 3. STATISTICAL SURVEYS............................9 3.1 Origin of Shots..........................9 3.2 Number of Shots.........................11 4. REPORTS OF TRAINED OBSERVERS...................14 4.1 Test Conditions.........................16 4.2 Analysis of Observers' Localization Responses...............................17 4.3 Loudness and Apparent Size of Acoustic Image...................................18 5. CONCLUSIONS..................................20 APPENDIX A. TRANSCRIPTION OF OBSERVERS' NOTES.........A-l iii iii 130 LIST OF FIGURES AND TABLES page Figure 1. Muzzle blast and shock waveforms from Mannlicher-Carcano....................................2 2. Loci of muzzle blast and shock waves at two times after firing of supersonic bullet...............4 3. Observers localizing source of sound along path of bullet........................................6 4. Observer location at Dealey Plaza....................15 Table I. Thompson's analysis of origin of shots..................9 II. House Committee analysis of origin of shots....10 III. Number of people reporting various origins as a function of the number of shots reported.......12 IV. Accuracy of forced-choice responses as to origin (TSBD or knoll).........................17 iv 131 1. INTRODUCTION The analysis of witness reports comprised (1) an examination of two compilations of testimony given by witnesses present in Dealey Plaza on November 22, 1963, (2) an analysis of how the sounds of gunfire in Dealey Plaza would be perceived by witnesses located at different areas in the Plaza, and (3) the reports of trained listeners who were present during the acoustical reconstruction on August 20, 1978. The two compilations examined were those by J. Thompson, in his book, Six Seconds in Dallas, and by members of the staff of the House Select Committee on Assassinations. All earwitness reports, whether of those present in Dealey Plaza in 1963 or of the experienced listeners in 1978, must be examined with an understanding of the characteristic acoustical behavior of gunfire in a reverberant space. Section 2 of this report explains how listeners can misjudge the source and number of shots in such a space. Section 3 reports the analysis of the two compilations mentioned above; Sec. 4 details the observations of trained listeners stationed in the Plaza during the acoustical reconstruction. 1 132 2. LOCALIZATION OF SOUND The nature of gunfire is such that three basic errors in Judgment relating to the source and the number of shots are possible: * confusion of the shock wave and the muzzle blast * front-back reversals * misjudgment of interfering echoes. The acoustic stimulus, or shot, has two primary components: the shock wave and muzzle blast (illustrated in Fig. 1); and several echoes, or reflections. FIG. 1. MUZZLE BLAST AND SHOCK WAVEFORMS FROM MANNLICHER-CARCANO. 2 133 Because a rifle bullet travels at supersonic speed, it generates a shock wave that spreads acoustically in the shape of a cone, with the bullet as the tip of the cone. The muzzle blast, which propagates at the speed of sound, spreads out spherically from the source. Both of these sounds are very loud. The shock Wave has a peak sound pressure level of about 135 dB re 2x10-5N/m2, and the muzzle blast, a peak of 157 dB re 2x10-5N/m(2), at l m. The time between arrivals of these two sounds at a given listener location can vary considerably, depending on the listener's position with respect to the location of the rifle and the path of the bullet. Since the amplitude of the shock wave diminishes as one over the distance from the source and the amplitude of the muzzle blast diminishes as one over the square of the distance from the source, the relative intensity of these two sounds also varies considerably from one listener location to another. At any reasonable distance, both the conical and spherical waves are essentially plane waves with respect to a small object such as an observer's head. Thus, to determine the apparent locus of the source, we need only take a perpendicular to the appropriate wavefront as it sweeps over the observer. Figure 2 shows the geometry of the two waves at two different times. The shock wave, at time 1, has just reached the observer; its apparent locus is along the path of the bullet on a perpendicular to the shock wave. At this time, the wave from the muzzle blast has not reached the observer. At time 2, when the blast wave has reached the observer, the apparent source of the shot is on a perpendicular to the plane of the spherical blast wave and, therefore, at the muzzle of the rifle. 3 134 FIG. 2. LOCI OF MUZZLE BLAST AND SHOCK WAVES AT TWO TIMES AFTER FIRING OF SUPERSONIC BULLET. 4 135 Dr. George Gariner confirmed this analysis at a test carried out with 20 to 30 observers at the Aberdeen Proving Ground. The observers were seated in rows parallel to the path of the bullet. The blast wave was muffled by firing the rifle through a small hole in an enclosed van. The reports of the observers are portrayed graphically in Fig. 3. About 75% of the observers pointed at the path of the bullet, while 25% pointed away from this path - but still perpendicular to the surface of the conical shock wave. This latter judgment is called a front-back reversal. If the sound of the shock wave were not so brief, an observer would have time to execute a head motion and tell whether the source was exactly in front of or behind him. However, the shock wave endures for only about 1 msec and the blast wave about 5 msec; some front-back reversals are therefore expected. Even if the muzzle blast is not silenced, the observer may be confused. The further the observer stands away from the muzzle and the nearer the path of the bullet, the more likely that localization of sound will be based on the shock wave and, hence, incorrect. Some muffling of the blast wave will occur if a rifle is fired from within an open window. Thus, in the acoustical reconstruction, the rifle was fired from two locations in the TSBD: (1) in the plane of the open sixth-floor window and (2) with the muzzle tip withdrawn 2 ft from the plane of the window. The buildings around the Plaza caused strong reverberations, or echoes, that followed the initial sound by from 0.5 to 1.5 sec. While these reflections caused no confusion to our listeners, who were prepared and expected ot hear them, they may well have 136 FIG. 3. OBSERVERS LOCALIZING SOURCE OF SOUND ALONG PATH OF BULLET. 6 137 inflated the number of shots reported by the suprised witnesses during the assassination. The source of these echoes can be predicted from the general geometry of the Plaza. For example, one hears a very strong reflection from the Post Office Annex that arrives about 1 sec after the shot, regardless of whether the rifle is fired from the TSBD or the knoll. Because of the long delay, a listener located on the knoll would recognize this as an echo but might place the source somewhere in back of him, anywhere from the TSBD to the railway overpass. From near the TSBD, a listener would hear a strong echo from the general vicinity of the railway overpass. However, since the initial disturbance, the shock wave from the bullet, would be almost directly overhead -- an anomalous locus, especially if the rifle had been fired from well within the TSBD - this echo would cause some confusion. The general area of the knoll, to the right of the bridge, would then be a prime candidate as the locus of the source. Even though this echo occurs 0.8 sec after the shock wave, it is the first sound that would make sense to the listener. On the other hand, listeners located near the railroad overpass would react to the very strong reflections from along Houston St. For listeners in the Plaza area, the location of the rifle muzzle relative to the window opening is a critical determiner of the perceived sound. The further inside the building the muzzle is located, the greater the potential for the shock wave to dominate perception. If the muzzle of the rifle had been withdrawn and, therefore, little or no blast were present for one or more of the shots in 1963, the localization judgments of people in the Plaza would have been based primarily on the shock wave, creating much uncertainty and lack of agreement. 7 138 During the reconstruction, echoes were heard from the new hotel, but they arrived some seconds after the primary sound and long after the earlier echoes from structures bordering the Plaza. The hotel echoes, therefore, did not interfere with the subjective evaluations in any way. 8 139 3. STATISTICAL SURVEYS 3.1 Origin of Shots According to Investigator J. Basteri, 692 people were present in the Plaza during the assassination. Two surveys of interviews and testimony given by some of these people have classified the witness reports as to the origin of gunfire into four categories: the TSBD, the Knoll, Other (not TSBD or Knoll), and Don't Know (origin uncertain). J. Thompson's compilation in Six Seconds in Dallas of 190 witness reports is summarized in Table I. TABLE I. THOMPSON'S ANALYSIS OF ORIGIN OF SHOTS. TSBD Knoll Other Don't Know Total 25 33 6 126 190 13.2% 17.3% 3.2% 66.3% 100% This sample of 190 is 27.4% of the total available witnesses. It is difficult to know what, if any, bias is present in the selection of these witnesses. The sheer size of the sample makes it difficult to believe that a sizable selection bias was present. It is also difficult to predict the effect of a selection bias, if one were present. How could one tell what the witness was likely to report prior to the interview? People were scattered over a large area of the Plaza, but we do not know if equal proportions were selected from each area. This factor could influence the results, since analyses reveal that a person located near the knoll was more likely to report the knoll as the origin of the shots than any other location; similarly, a person located near the TSBD was more likely to report the TSBD as the origin of the shots than any other location. 9 140 The House Committee compilation is drawn from witness interviews by the Dallas Police Department and the FBI and from sworn testimony in the Warren Report. The total number of reports in this survey is 178. With very few exceptions, all these people appeared in the 190 sampled by Thompson. Similar sample-selection uncertainties apply here as well. The House Committee analysis is summarized in Table II. TABLE II. HOUSE COMMITTEE ANALYSIS OF ORGIN OF SHOTS. TSBD KNOLL OTHER DON'T KNOW TOTAL 49 21 30 78 178 27.5% 11.8% 16.9% 43.8% 100% Over half the sample had some opinion as to the origin of the shot; the majority of these reported the origin as the TSBD. Twenty-one witnesses reported the Knoll as the source, 30 reported some Other location, and only 4 witnesses gave more than a single location for the shots. The Four reporting a dual or multiple location are counted as "Other" in Table II. Of the 49 witnesses pointing at TSBD, 13 were at the depository itself, 16 were in the motorcade, and the remainder were scattered throughout the area, including at the Sheriff's Office, the overpass, the knoll, and the triangular park. A breakdown of these reporting the knoll as the origin of the shots show that 2 of 21 were located on the knoll. Eight were on the curb along Elm St. on the knoll side or on that side of the motorcade traveling down Elm St. Four were near the TSBD. One was on the east side of Houston. Five were in 10 141 the triangular area bordered by Elm, Houston, and Main, and one was on the railroad overpass. An analysis of the "Other" responses showed no obvious pattern. Some witnesses at the TSBD point toward Houston St.; others point down Elm. Similarly, those at the Sheriff's Office point in an arc ranging from west of TSBD to the railroad overpass. Comparing this statistical analysis with Thompson's, the most striking discrepancy is the relatively low percentage of witnesses reporting origins other than the knoll or the TSBD in Thompson's compilation. Another important difference is in the relative number of people pointing at the TSBD is the knoll. Although the categorization of a given response is somewhat arbitrary, the major discrepancy in the two compilations must be laid to a difference in classification of responses making up the compilations. Zapruder is listed in the Thompson survey as pointing to the knoll, while his sworn testimony before the Warren Commission was as follows:* Liebeler: But you didn't form any opinion at that time as to what direction the shots did come from actually? Zapruder: No. Hence, House Committee staff placed his response in the "Don't Know" category. 3.2 Number of Shots The House Committee compilation also categorized witness responses according to number of shots attributed to the four --------------------------------------- *Warren Report, Vol. 7, P. 572. ll 11 142 different categories of origin. This analysis is summarized in Table III. TABLE III. NUMBER OF PEOPLE REPORTING VARIOUS ORIGINS AS A FUNCTION OF THE NUMBER OF SHOTS REPORTED No. of Shots Reported Reported Origin Don't of Shot 2 2 or 3 3 4 Know Total TSBD 3 2 38 2 1 16 (4.5) (1.9) (35.5) (1.6) (2.4) Knoll 5 2 1 0 2 20 (2.0) (0.8) (15.4) (0.7) (1.1) Other 2 1 22 3 1 29 (2.9) (1.2) (22) (1.0) (1.5) Don't 7 2 61 1 5 76 Know (7.5) (3.1) (58.6) (2.7) (4.0) Total 17 7 132 6 9 171(+) *Expected number of judgments if origin and number of shots were independent judgments. +Seven other witnesses report 1, 4-5, 5, 6, or 8 shots. Reports as to the number of shots range from 1 to 8. Of the 178 witnesses, however, the vast majority, 74.2% (132/178), reported 3 shots, and the mean number reported was 2.98. Given the scatter in the reported sources of the gunfire, one tenable hypothesis is that only people in certain locations might hear the knoll shot. We therefore sought to investigate to what extent the data matrix was interrelated, i.e., to what extent does one Judgment influence the other? One test for 12 143 this interrelation is to assume the converse --namely, that the Judgments are independent and to determine how well we can predict the entire data matrix on the basis of this hypothesis. The expected number, which is given in parenthesis beneath the number of people actually reporting, is calculated by determining the probability of each report From the margins and assuming that a particular cell, the intersection of that row and column, can be calculated from the product of the probabilities. For example, 20/171 = .117 report the shot coming from the knoll and 132/171 = .772 reported B shots. Thus, the Joint occurrence of both events, assuming they are independent, is (.772) (.117) = .09, and the expected number of such reports is (.09) (171) = 15.4. The number of people reporting shots in this cell of the matrix is 11, 4 or 5 fewer than expected. By and large, the predictions are excellent, and there is no reason to suspect that the two responses are other than independent. 13 144 4. REPORTS OF TRAINED OBSERVERS On August 20, 1978, Dr. Dennis McFadden of the Psychology Department of the University of Texas and Dr. Frederick Wightman of the Department of Audlology at Northwestern University listened to the three sequences of shots fired during the acoustical reconstruction and recorded their impressions. Appendix A contains a transcription of their notes. Their reports concerned the apparent origin of shots, any apparent secondary sources or echoes, how loud the shots were, and any other remarks they felt appropriate. Initially, we were uncertain as to how easy it would be to determine the correct location and what degree of consistency there would be among the observers. Hence, for the first sequence, and during most of the second, the observers were located about 1 m apart and in such a way that I could see and compare their responses. The approximate observer locations each sequence are indicated in Fig. 4. During the first sequence, Dr. Wightman correctly localized all 17 shots, and Dr. McFadden missed only l. Their general qualitative descriptions and descriptions of the reverberations were also highly consistent. We were, therefore, more confident about the consistency of the reports, and during the latter part of the second sequence, Dr. McFadden moved from his original location at the curb at the top of Elm directly in front of the TSBD, to across Elm on the southwest corner of Elm and Houston. For the third sequence, Dr. Wightman and I observed from the grassy triangle formed by Elm, Houston, and Main Sts., while Dr. McFadden observed from the railroad tracks, above the northern curb of Elm. 14 145 FIG. 4. OBSERVER LOCATIONS AT DEALEY PLAZA. 146 My own impressions and the reports of Dr. William Hartmann, the investigator of the "Jiggle analysis," were very similar to those of McFadden and Wightman, although my own (hearing )is impaired by about 50 dB in my left ear. The primary manifestation of this difficulty was my failure to hear some echoes if they occurred to my left. Thus, it would seem that our observers, because of their special training and experience, are only slightly more acute concerning nuances of the echoes and reverberations and, perhaps, in separating the shock wave and the blast wave than are untrained people. The emotional condition of our observers during the test and the emotional condition of the people during the assassination were undoubtedly quite different. The influence of such emotion on the localization Judgment may be quite large, but there is no way to quantify this factor. 4.1 Test Conditions The shot sequence was unknown to both of the observers. Because repeats of certain shots were requested during the sequence, I was also uncertain --despite knowing the planned sequence. We requested three motorcycles to be running during the test to provide some background noise that would approximate the original listening conditions in Dealey Plaza. Unfortunately, these newer motorcycles were not very noisy, but the shots were so loud that any reasonable level of background noise would have been low in comparison with the shots themselves. Our listening conditions were, therefore, essentially representative of those at the time of the assassination, except for our being able to hear some very-low-level, long-delay echoes that originally might have been inaudible. 16 147 Our observers did know that there were only two possible locations for the marksman, whereas there was considerably more uncertainty on this issue at the time of the assassination. Signal uncertainty of this kind generally does not seriously degrade the accuracy of Judgments, but it does depend on the number of potential alternatives. In this case, as we shall see, the localization reports made by the trained listeners were, for the most part, of general areas, rather than specific windows of a building. The total number of potential locations was not, therefore, large and, thus, was likely to be representative of localization responses given at the time of the assassination. 4.2 Analysis of Observers' Localization Responses The descriptive comments made by the observers are difficult to compare with any degree of precision. However, there was clear agreement in their reports with respect to the apparent loudness of the sounds and echoes and the apparent size of the acoustic image. After each test shot, we asked the two observers to guess whether the shot was fired from the TSBD or the knoll, independent of what the apparent locus might be. Table IV is an analysis of this forced-choice data. TABLE IV. ACCURACY OF FORCED-CHOICE RESPONSES AS TO ORIGIN (TSBD OR KNOLL) Sequence Dr. Wightman Dr. McFadden ------------------------------------------------------------------ 1 12/12 100% 11/12 92% 2 11/15 73% 14/15 93% 3 19/25 76% 23/25 92% Overall 47/57 82% 53/57 93% ------------------------------------------------------------------ Overall Agreement 82% 17 148 The average accuracy of the reports is nearly 90%, and the consistency between the two observers is 82%. Also, the average accuracy is nearly exactly the same whether the shot came from the TSBD or the knoll. Thus, this analysis shows high accuracy in localizing the source of the sound and reasonably good consistency. 4.3 Loudness and Apparent Size of Acoustic Image All observers rated the rifle shots as very very loud, and they were unable to understand how they could have been described as a firecracker or backfire. Only the pistol, which was subsonic, produced a moderate loudness. Practically all the rifle shots, whether fired from the knoll or the TSBD, appeared to be diffuse and to occupy a very large acoustic space. For example, the sound did not seem to come from the sixth floor window of the TSBD, but from the right upper side of the building. This apparently large source location may be a result of acoustic scatter of the muzzle blast -either because of the building in the case of the TSBD or because of the trees in the case of the knoll. Only the pistol shot appears to have a reasonably constrained acoustic image and, for that reason, could be localized with some precision. One might consider whether silencers would change the apparent loudness of the size of the image. The Garinther-Moreland study* reports the average attenuation produced by a number of silencers as being about 18 dB for all weapon-silencer combinations. Sound from the supersonic weapons tested were attenuated ---------------------------------------- *"Acoustical Considerations for a Silent Weapon System: A Feasibility Study," 1966, p. 70. 18 149 by 18.6 dB and 37.5 dB, but even with this reduction, the peak overpressure was still very large. Two rifle-silencer combinations produced peak overpressures of 138 dB and 120 dB at 3.8 m, clearly loud enough to be easy to locate and clearly audible above the motorcycle and crowd noise. 19 150 5. CONCLUSIONS It is difficult to draw any firm conclusions relating the reports of witnesses in the Plaza to the possible locus of any assassin. Confusion between the shock wave and muzzle blast front-back reversals, confusion caused by echoes, and the startle of the witness could all be used to impeach the testimony of any particular witness. There is no way of knowing which, if any, of these factors was most significant with respect to any single observation made on November 22, 1963. Thus, one witness can be assigned no more credibility than any other. For example, even if a shot was fired from the TSBD, the witnesses standing on the knoll would likely report the source of the shot in the following way. The witness would presumably localize on the basis Of the shock wave. With the path of the bullet behind the President's car, the witness would perceive the apparent locus of the shot as being on a line from himself to the bullet's path -- i.e., in the street or open park behind the path of the bullet. ,Since this location is impossible, a front-back reversal is likely. This front-back reversal would place the source 180(deg). behind the bullet path and, hence, on the knoll. Despite this uncertainty, two general remarks seem worthwhile--one based on the test, the other on the statistical analysis. First, it is hard to believe a rifle was fired from the knoll. Such a shot would be extremely loud, even if silenced, and it would be hard to imagine anyone in the vicinity of the knoll missing such an event. An unsilenced pistol firing subsonic bullets also seems unlikely because this shot was the easiest to localize of all the shots fired. It produced the least reverberation. As an acoustic image, it was much sharper 20 151 and less diffuse than that of the rifle, sounding much like a firecracker. It is, however, conceivable that had a pistol been fired from the knoll at about the same time a rifle was fired from the TSBD the pistol shot would have been less easily localized, or even completely masked from some vantage points. As an isolated shot, however, it is extremely easy to localize. Finally, if one accepts the hypothesis that a marksman fired from the knoll and that other shots were fired from some other location, then it seems most unlikely that only 4 of 178 witnesses would report a single location as the origin of the shots. Despite the various causes of confusion in the locus of any single shot, a second shot from a different location should be distinctive and different enough to cause more than four witnesses to report multiple origins for the shots. 21 152 APPENDIX A. TRANSCRIPTION OF OBSERVERS' NOTES The tabular information in this appendix was transcribed from notes made during the acoustical reconstruction on August 20, 1978 by two trained observers --Dennis McFadden and Frederick Wightman. Included in this table, along with their responses, are the number of the shot in each sequence of test firing, the origin of the shot, and the target fired upon. For convenience in determining the positions of rifle, target, and listener, the reader may refer to Fig. 4 of this report. Abbreviations used within the table are as follows: * T always refers to the TSBD and K to the knoll. * In the column headed origin, Tp means the rifle was fired in the plane of the sixth floor window of the TSBD, T2 means the muzzle was withdrawn 2 ft from the plane of the window, K indicates a rifle shot from the knoll, and Kp represents a pistol shot from the knoll. A-1 153 A.1 OBSERVER: DENNIS MCFADDEN A-2 154 A.1 cont. A-3 155 A.1 cont. A-4 156 A.1 cont. A-5 157 A.1 cont. A-6 158 A.1 cont. A-7 159 A.1 cont. A-8 160 A.1 cont. A-9 161 A.1 cont. A-10 162 A.1 cont. A-11 163 A.1 cont. A-12 164 A.2 OBSERVER: FRED WIGHTMAN A-13 165 A.2 cont. A-14 166 A.2 cont. A-15 167 A.2 cont. A-16 168 A.2 cont. A-17 169 A.2 cont. A-18 170 A.2 cont. A-19 171 ADDENDUM A: REPORT ON THE TEMPERATURE IN DALLAS, TEX., NOVEMBER 22, 1963 172 ADDENDUM A: cont. 173 ADDENDUM A: cont. 174 ADDENDUM A: cont. 175 ADDENDUM B: REPORT ON WIND CONDITIONS IN DALLAS, TEX., NOVEMBER 22, 1963 176 ADDENDUM B: cont. 177 ADDENDUM B: cont. 178 ADDENDUM B: cont. 179 ADDENDUM B: cont. 180 ADDENDUM B: cont. 181 ADDENDUM B: cont. 182 ADDENDUM B: cont. 183 ADDENDUM C: MEMORANDUM FROM G. ROBERT BLAKEY TO THE SELECT COMMITTEE ON ASSASSINATIONS ON THE MANNLICHER-CARCANO FIRING TEST MEMORANDUM TO: ALL COMMITTEE MEMBERS FROM: G. Robert Blakey, Chief Counsel and Director SUBJECT: Test on Mannlicher-Carcano DATE: March 22, 1979 Yesterday, with the assistance of Sgt. Cecil Kirk and other members of the D.C. Police Department, the staff conducted a second test of the time necessary to fire two consecutive rounds from a 6.5 mm Mannlicher-Carcano fifle similar to that found on the 6th floor of the Texas School Book Depository on November 22, 1963. The test was conducted primarily to answer the question, would it have been possible for Lee Harvey Oswald to fire two shots in less than 1.7 seconds? OUr test shows that it is. As you recall, the estimated trigger pulls for the shots that the acoustics analysis identified as #1 and #2 occurred approximately 1.66 seconds apart. (See my previous memo on correlating the shots) In addition, the test was designed to provide some insight into the difficulty Oswald would have encountered in firing three consecutive shots within 8.31 seconds, at least two of which were less than 1.7 seconds apart, and at least two of which hit the targets at the noted ranges. From knowledge of the difficulty involved in so shooting, it may be possible indirectly to infer something about the probability, as opposed to the possibility, that Oswald did so. Nevertheless, even the most improbable event may have occurred. Thus, to answer the ultimate question of whether Oswald did fire the first two shots 1.66 seconds apart and hit his target at least once in so doing, as much information as available in addition to that gathered in yesterday's testing should obviously be taken into consideration. This, of course, was what the Committee did in reaching its decisions on December 29, 1978, when it reviewed the previous test firing data, together with other evidence such as the acoustics analysis, and the physical evidence (e.g. the three empty shell casings found on the TSBD 6th floor). The test was conducted yesterday between 10:00 a.m. and noon at the Lorton Correctional facility firing range in Virginia. The National Archives, represented by Mr. David Paynter, brought the Oswald rifle (C.E. 139) for use in the test, but bench rest firing tests and operation of the weapon established that it was in too poor condition to be used. The Committee's Firearms Panel had previously noted the weapon's deterioration since 1963, and their final report reflects the specific nature of the deterioration). Consequently, a similar weapon was used for the actual testing. This rifle was one of the two previously used in August, 1978 for the tests in Dealey Plaza and will be turned over to the Archives as part of the Committee's files at the end of this month. 184 ADDENDUM C: cont. The shots were fired from a two story tower (approximately 20 feet high), at three targets, stationed from left to right at distances of 143, 165 and 266 feet from the tower. [1] The rifle was shot by four expert marksmen from the D.C.P.D., Officers D.M. Smith, B.L. Miller, Joe Masson, and E.E. Lewis, and two inexperienced staff members, deputy Chief Counsel Gary Cornwell and myself. Also present were Sgt. Cecil Kirk and Officer M.D. Gonzales, the D.C.P.D. Range Instructor. All members of the D.C.P.D. who fired the rifle had prior military experience. Officers Lewis and Smith had additional extensive civilian training in the use of rifles, while officers Miller and Masson had similar extensive training in the use of handguns. Each of the officers thus can be considered experts in the use of such weapons. Gary Cornwell and I have had neither military nor civilian training in the use of firearms, although I hunted with rifles as a boy, and Cornwell has hunted with rifles periodically throughout his adult life. Each shooter practiced working the bolt for several minutes (usually 2 to 3 minutes) before shooting. All shots were fired using open iron sights. All times were determined by 3 handheld stop watches. only 35 shells were fired, including those expended in preliminary tests to determine if the weapon operated properly. [2] Each officer fired two series of three shots and Cornwell and I each fired one series of two shots. The test established the following: (1) The weapon can be quite accurately fired more rapidly using open iron sights than the FBI tests in 1963 indicated, where the telescopic sight was used. For example, Officer Masson, during one test series, hit the body silhouette at 143 and 165 feet on the first two shots, and missed the head portion of the silhouette at 266 feet on the third shot by approximately one inch (1"), taking 2.0 seconds between shots 1 and 2, and a total of less than 5 seconds for all three shots. Two other series, one by officer Smith and another, again, by Officer Masson, were fired in which only 1.9 seconds elapsed between two shots, and one of the three shots scored a "kill". [3] ----------------------------------- [1] The distances were chosen upon the assumption that the 4th shot (Oswald's third) hit the President in the head at frame 312. [2] We found that the weapon was characteristically difficult to operate, due to its poor basic design, and in addition, the particular weapon we used had badly worn riflings and therefore shot somewhat inaccurately. [3] Normal target range body silhouettes, portraying an individual from waist to head, were used as targets. A "kill" was judged to be any shot that hit the silhouette. A "miss" was scored even if the bullet struck the target background, but not within the silhouette. 185 ADDENDUM C: cont. (2) It is apparently difficult, but not impossible -- at least with only minimal practice with the firearm used -- to fire 3 shots, at least two of which score "kills", with an elapsed time of 1.7 seconds or less between any two shots, even though in the limited testing conducted, no shooter achieved this degree of proficiency. (3) It is not difficult to fire two consecutive shots from a Mannlicher-Carcano within 1.66 seconds, and to "point aim", if not carefully "sight" it, on the target of each shot. Cornwell fired the rifle twice in 1.2 seconds, and I fired it twice within 1.5 seconds. In both cases the second shot missed, but was close to the silhouette. In fact, my second shot only missed the silhouette by approximately 2". [4] (4) There was ample time for Oswald to have fired 3 shots, hitting with two of them, within 8.31 seconds. All series of 3 shots were fired in less than 8 seconds, two were fired in less than 7 seconds, two in less than 6, and two in less than 5. [5] ---------------------------------- [4] The first shot in the test series, of course routinely scored "kills" since there was no time pressure imposed in aiming the rifle in preparation for that shot. [5] In light of the difficulty involved in making the first two shots in 1.66, I note that showing that it is possible does not offer any reason why he would have acted so quickly after the first miss. 186 (blank page) 187 THE ANALYSIS OF YURI NOSENKO'S POLYGRAPH EXAMINATION Submitted by Richard O. Arther, President, Scientific Lie Detection, Inc., New York, N.Y., and Director, National Training Center on Polygraph Science Report to the Select Committee on Assassinations U.S. House of Representatives Ninety-fifth Congress Second Session March 1979 (187) CONTENTS Paragraph Introduction........................................................1 Selection of the expert.............................................8 Procedures.........................................................11 A polygraph examination ...........................................13 Findings and conclusions of Richard O. Arther......................18 Materials examined ...............................................18 Procedures.........................................................21 Evaluation of the polygraph examinations...........................27 Comparison of the 1966 and 1968 examinations.......................52 Opinions .........................................................55 (188) INTRODUCTION* (1) * * As part of its investigation into the possibility that Lee Harvey Oswald was involved in a conspiracy to assassinate Jokn F. Kennedy, the select committee looked into whether he might have been a Soviet agent. (2) One controversial source of information on this point has been former high-ranking KGB official, Yuri Ivanovich Nosenko. Nosenko had been, on two occasions, in charge of coordinating surveillance and recruitment of American tourists in Russia. At the time of Oswald's defection to Russia, Nosenko claimed to have personally reviewed Oswald's file. (3) In February 1964, Nosenko defected to the United States and was placed under custody of the Central Intelligence Agency. Because strong doubts within the Agency that Nosenko was a bona fide defector, he was later placed in solitary confinement for 3 years. He was subjected to extensive interrogation, and during three periods took 1964; October 18, 1966; and August 6, 1968. The examinations were wide-ranging, but only the second dealt with Oswald in any depth. On all occasions, Nosenko maintained categorically that the KGB had never been interested in Oswald and had never used him as an agent. (4) The polygraphist conducting the first two tests concluded that on the first test Nosenko had lied, though not to the Oswald question. On the second, he had lied to two of the Oswald questions. Another polygraphist conducted the third test. He concluded that Nosenko was answering truthfully. (5) In the 1970's, the CIA investigated the overall handling of the Nosenko matter and concluded, with respect to the first two polygraph tests, that they should be considered "invalid or inconclusive" because deficiencies in the way they were conducted. For example, the first had been designed principally to create a hostile atmosphere for Nosenko. The polygraphist was instructed to tell Nosenko that the tests showed he was lying, regardless of what they actually showed. (The expert, in fact, interpreted the results as showing that Nosenko was lying.) However, the CIA did conclude that the third examina- tion was valid and that the results could be considered credible. (6) The Warren Commission was aware of the Nosenko issue, but was unable to make much of it since most of the material was classified and unavailable. Similarly, critics of the Warren Commission have not dealt with it in any depth. ---------------------------- * Materials submitted lot this report by the committee's polygraph consultant were compiled by HSCA staff members G. Robert Blakey and Whitney Warriss. ** Arabic numerals in parentheses at the beginning of paragraphs indicate the paragraph number for purposes of citation and referencing; italic numerals in parentheses in the middle or at the end of sentences indicate references which can be found at the end of each report or section. (189) 190 (7) The select committee decided to have an independent analysis of the polygraph tests conducted. First, such an examination had never been carried out. Second, it wished to know if the tests had been properly conducted and interpreted and if the answers could be considered credible. If so, then it could be stated with considerable certainty that Nosenko was a valuable source of information. If not, the committee would explore other avenues in order to decide what, if any, relation Oswald had to the KGB. Selection of the expert (8) The committee retained Richard O. Arther to conduct an independent analysis of the three polygraph tests taken by Nosenko. Arther had been a member of the committee's polygraph panel that examined the Jack Ruby and James Earl Ray polygraph tests. He had been selected because of his extensive qualifications and lack of prior involvement with either assassination investigation. (9) Arther received a B.S. with honors in police science from Michigan State University in 1951, and an M.A. in psychology from Colombia University in 1960. Arther has been in private practice in New York City since 1963. He rounded Scientific Lie Detection, Inc., and cofounded the National Training Center of Polygraph Science. He has taught at Brooklyn College, Seton Hall University, the John Jay College of Criminal Justice and the Graduate School of Public Administration of New York University. (10) Arther has authored over 200 professional articles and two books. He is a member of the Academy of Certified Polygraphists and the American Polygraph Association. Procedures (11) As noted, Arther was asked to analyze the material related to the three examinations to determine if they had been validly conducted and interpreted and if the results were credible. On June 2, 1978, he made the first of three trips to CIA headquarters in Langley, Va. Following proceders standard for an analysis of past polygraph tests, he reviewed the polygraph charts "blind," that, is, without any knowledge of whether the questions were control, relevant, or irrelevant. The purpose was to try to determine solely from the tracings on the charts to which questions Nosenko appeared to be lying. This procedure was followed on two separate occasions. After each review, Arther then checked the question sheets to determine which questions were control, relevant, or irrelevant (see below for an explanation of these terms). (12) The other trips were made on June 7 and August 24. Subsequently, Arther submitted his final report, which appears in full following this introductory section. A polygraph examination (13) A polygraph examination records physiological responses to questions asked. The polygraphist attempts to design the examination in such a way that the truthful person will react to the control questions and the lying person to the relevant questions The test structure must be constructed so that it poses a threat to both the truthful and untruthful person. The polygraphist attempts to determine the "psychological set" of the examinee. He tries to determine, by reading the physiological activity of the examinee in the polygraph charts, what 191 questions or question areas pose the greatest threat to the examinee's well-being. A "psychological set" is "a person's fears, anxieties, and apprehension, [which] are channeled toward that situation causing the greatest threat to the individual's well-being. He will tune in on that which is of a greater threat, and tune out that of a lesser threat." (14) Responses to questions are recorded on a polygraph chart, which consists of tracings produced by three different types of psychological reactions associated with the circulatory, nervous, and respiratory systems: 1. The breathing pattern is recorded by means of a rubber tube placed around the person's chest. 2. The Galvanic skin response is measured by placing the attachments on either the fingers or the palms. 3. Changes in blood pressure, heart beat, and pulse rate are obtained by a standard blood pressure cuff placed around the upper arm. (15) Questions are broken down into three categories: 1. Relevant--those pertinent to the investigation. 2. Irrelevant--hopefully, meaningless, nonemotion-producing ones to get the person used to being, questioned and giving answers. 3. Control--nonrelevant, to which it can be assumed the person will lie during the test. These provide a standard for comparing the responses to relevant questions. If a person reacts more to a proper control question than to the relevant questions, then he is considered to be truthful to the relevants. On the other hand, if he reacts more to the relevants than to the proper control question, he is considered to be lying to the relevants. (16) Relevant, irrevelant, and control questions are interspersed throughout the polygraph chart. The examination may consist of various series covering, various relevant issues. Each relevant issue must be asked a minimum of two times in a series, but as many times as necessary to conclude that relevant issue successfully. Each series should have a minimum of two charts, but as many charts as necessary to conclude the relevant issues in that series successfully. (17) The procedure for a polygraph examination is as follows:The polygraphist first conducts a pretest interview, during which the test questions are read to the person exactly as they are going to be asked. It is vital that all questions be properly worded and discussed with the person. Then the actual test is conducted. FINDINGS AND CONCLUSIONS OF RICHARD O. ARTHER Materials examined (18) On June 2, 1978, I went to Central Intelligence Agency headquarters to study the polygraph examinations administered by the CIA to Yuri Ivanovich Nosenko. I was given what they claimed was the complete file. When I asked for the polygraphists handwritten notes, handwritten question sheets, chart analyses and other papers from the examinations, I was again told I had the complete file. This amazed me, since I had been given only official reports, typed test --------------------------------- *From the Curriculum of the U.S. Army Provost Marshal General Polygraph School, Ft. McClellan, Georgia. 192 questions and charts. Handwritten notes have always been included in every polygraph file I have ever reviewed. Either on this day, June 2, or on June 7 (the date of any second visit), I asked for the tape record ings from the examinations. I was told there were none. This also greatly surprised me. (19) On both June 2 and June 7, CIA polygraphists were assigned to me to provide all the background information they had on all three examinations. I was assured that they were holding nothing back. (20) My third trip to the CIA headquarters was on August 24. Again I had a polygraphist assigned to me. I was given only material provided in June. Procedures June 2 visit (21) The purpose of this visit was to get an overview of Nosenko's polygraph examinations, including the quality of the test questions and esting procedures, and to conduct an analysis of the polygraph recordings to determine if I agreed with the interpretations of the CIA polygraph experts. (22) I spent the first several hours analyzing the polygraph reactions-without knowing if any given question was a relevant, irrelevant, or control Such a procedure is referred to as a "blind chart analysis" and is a standard one, designed to eliminate all preconceived opinions a polygraphist might have as to a persons truthfulness. That is, I formed my opinions as to Nosenko's truthfulness to each test question prior to knowing if any given question was a relevant, irrelevant, or control. (23) Only after I finished this blind chart analysis did I learn which questions were relevant, irrelevant, or control. I then determined if I agreed with the CIA expert's analysis of Nosenko's polygraph recordings. (24) On June 2, Kenneth Klein, committee counsel, asked if I wanted to conduct my own polygraph examination of Nosenko and/or personally interview the two CIA polygraph experts. I replied that I would consider both possibilities. June 7 visit On June 7, I returned to CIA headquarters to reevaluate the polygraph examinations, decide if Nosenko should be given another polygraph examination, and determine if interviews of the two CIA experts would Drove beneficial. I also did another blind chart analysis to determine if I was consistent with my June 2 analysis. The results were substantially identical. August 24 visit (26) The objective of this visit was to reevaluate the charts and question sheets to make sure that my preliminary written report was as accurate as possible. I had had to write it from memory as the CIA requested I not take my notes away from the Agency's control. Evaluation of the polygraph examinations April 4, 1964 (27) The April 4, 1964, examination was administered exactly 2 months after Nosenko had defected. It consisted of more than 50 relevant questions, divided into 13 individual tests. (The great major- 193 ity of polygraph examinations are limited to three or four relevant issues.) (28) It was obvious that the CIA's purpose was to determine Nosenko's truthfulness to a wide variety of issues. Only one question in one test dealt with Lee Harvey Oswald: "Did you tell us the truth about Lee Harvey Oswald?" The answer was "Yes." (29) The wording of this question is very general. It is the type of broad question that many polygraphists use only at the very end of a test, after at least three or four relevant questions have been asked on the same issue. (30) Further, this question was the 51st one asked. It occurred in the 12th test and was the 3rd of 11 questions in the test. Because important questions are generally placed at the beginning, with questions of lesser importance near the rear, it would appear that the Oswald issue had an extremely low priority. (31) As noted, in this examination over 50 relevant questions were asked. Fred E. Inbau and John E. Reid, authors of the classic textbook on polygraphy, Lie Detection & Criminal Interrogation (3d edition, 1953), recommended that no more than three relevant test questions be asked. This is because the more a person is asked relevant questions, the more likely he will become "test-tired," that is, even though lying, he will not react because he has become emotionally exhausted. (32) Further compounding this situation, the examination started at 10:45 a.m. and ended at 3:15 p.m.--a period of 4 1/2 hours--whereas the usual polygraph examination lasts less than 2 hours, with four or five separate tests. Again there is a definite risk that a person will become "test-tired" if the examination runs too long. (33) Although the CIA expert's opinion was that Nosenko gave a "reaction" (I presume by this he means that Nosenko was "lying") to 6 of the 11 questions, he listed Nosenko as showing "no reaction" to the Oswald question. (34) In both my blind chart analyses, I picked the Oswald question as showing the greatest valid "lie" reaction by Nosenko, certainly greater than those for the six questions indicated by the CIA expert as having produced lies. (35) In spite of all the above problems, which would normally lead a polygraphist to believe that Nosenko should be "emotionally unresponsive," Nosenko gives a substantial "lie" reaction to the Oswald question. October 18, 1966 (36) The October 18, 1966, examination was administered by the same CIA polygraphist who had administered Nosenko's 1964 examination. In his written report, dated October 23, 1966, he stated: (37) The specific purpose of the October 18, 1966, polygraph test was to: a. Attempt to establish whether subject was in fact actually involved in the Oswald case while Oswald was in the Soviet Union, or if his association with the Oswald case was only part of his cover story legend. b. Determine if subject was personally active in the Oswald case in 1963 after President Kennedy's assassination. 194 c. Ascertain if subject received special instructions from KGB to pass on to the American Government regarding the Oswald case. (38) This series of examinations began on October 18 and ended on October 28. The thrust of the first day of examinations had to do with Oswald. The subsequent examinations, that is, October 19 through October 28, had nothing to do with Oswald. It would appear that the CIA now fully appreciated the significance of Nosenko/Oswald, and that their polygraphist was doing his best to determine Nosenko's truthfulness regarding Oswald. (39) During the examination, Nosenko was asked 32 questions in which the name Oswald appears. On my blind analysis, I selected the following questions as containing valid indicators of lying: 1. Did you receive special instructions about what to tell Americans about the Oswald case? (No) 2. Was Oswald recruited by the KGB as an agent? (No) 3. Did the KGB consider Oswald abnormal? (Yes) 4. To your knowledge did Oswald talk to a KGB officer in Mexico? 5. Is your contact with the Oswald case part of your legend? 6. Did you hear of Oswald prior to President Kennedy's assassination? (Yes) 7. Did you hear of Oswald only after President Kennedy's assassination? (No) 8. Did you personally order __________________in 1959, to col- lect material on Oswald? (Yes) 9. Did the KGB instruct you to tell us Oswald was a bad shot? (No) 10. Did the KGB give the Oswalds any kind of help in their departure from the Soviet Union? (No) (40) When a liar is asked a large number of relevant test questions, he will not react as lying to all questions. Instead he will pick out the questions most significant to him and react as lying only to those. Generally, the questions he does not regard as significant, he will not react to, even though he is lying. (41) On test series 1, the CIA expert wrote that the "most significant reactions" were to questions 1 and 6 above. For test series 2, the CIA expert wrote that the "most significant reactions" were to questions 5, 6 and 7 above, plus two questions not on my list.* (42) By having the Oswald questions the first clay of this second series of polygraph examinations, both the validity and reliability were greatly increased. AUGUST 6, 1968 (43) The third series of polygraph examinations was administered in August 1968. These examinations were conducted by a different CIA polygraph expert. The first series of tests was administered on August 2. ------------------------------------- *Since my blind analysis involved selecting only the two or three questions to which Nosenko was reacting the most strongly within each test, I did not expect to agree fully with the CIA expert. 195 (44) Twenty-three relevant test questions were asked, but not one had to do with Oswald. The second day of testing was August 6, 1968. At this time, 27 relevant questions preceded the first Oswald question, of which there were 2. (45) It is obvious that once again the Oswald issue was considered extremely minor. As noted, the Oswald questions did not occur until quite far into the procedure. The longer a question is postponed, the more likely a liar will come out as "truthful" because he has become "test tired" that is unresponsive. On the first day, the polygraphist himself acknowledged the possibility of Nosenko's becoming unre- sponsive when he wrote, after the sixth test of August 2, 1968: No further polygraph tests were administered on this date because the examiner did not want to run the risk of fatigue setting in and thus possibly causing adrenalin exhaustion. (46) Thus he stopped on August 2, after 6 tests and 23 relevant questions. Yet on the second day of testing (August 6), it was not until test 7 and the 28th relevant question that he first asked about Oswald. (47) Further, the wording of the two Oswald questions was very startling: 1. Did you actually review the KGB file on Oswald? (Yes) 2. Did Lee Harvey Oswald receive any KGB training or assignments? (No) (48) No date was referred to within this first question, a serious error in wording. Nosenko was claiming that he had reviewed Oswald's file before the assassination. Therefore, the question should have been worded: (49) "Before November 1963, had you actually reviewed Oswald's KGB file?" Leaving out the date meant that Nosenko could have truthfully answered this question even if he had first reviewed Oswald's file after the assassination. In fact, he could have reviewed it 1 week before he was told to defect and still come out as truthful to the question. (50) The second question is also very poor in that it has the word "or" in it, which automatically means that it is really two questions. When there are two questions within one question, if a person happens to be truthful to one of those questions and lying about the other, generally he will come out as truthful. (51) For example, if Oswald did not receive any KGB training but was told to assassinate President Kennedy, Nosenko could possibly truthfully answer "yes" to this question. Comparison of 1966 and 1968 examinations (52) Not only was the first day of the 1966 examination directed totally toward the Oswald issue, but the questions were very specific and basically worded properly. In 1968, neither was the case. (53) In 1966, the CIA polygraph expert rendered an opinion that Nosenko was lying both about why he defected and as about Oswald. On the other hand, in 1968, the polygraphist rendered an opinion that Nosenko was "substantially truthful." This second expert even had Nosenko answering truthfully to the question: "Is there any possibility that the KGB would dispatch an officer to defect to the Americans? Answer: "No." 196 (54) The HSCA has informed me that without exception every intelligence officer interviewed--including KGB defectors--has stated that the KGB is capable of dispatching an officer to defect. The fact that Nosenko denies this and the polygraphist finds him truthful makes the entire examination suspect. Opinions (55) 1. For two major reasons, there would be no point in interviewing the two CIA polygraph experts. First, the charts spoke for themselves. Second, since I supposedly had the complete case file, I would rather go by the file than by someone's memory of what happened some 10 to 14 years ago. (56) 2. Another polygraph examination is not recommended for Nosenko. After such a long period of time and such extensive testing, the results could not be trusted. (57) 3. The polygraph examination given on October 18, 1966, should be considered the most valid and reliable of the, three regarding Lee Harvey Oswald. Given the state of the art in 1966, this examination met the criteria of validity and reliability. (58) 4. Both the 1964 and 1968 examinations involving Lee Harvey Oswald should be disregarded because of the large number of inherent deficiencies in both examinations. (59) 5. On another occasion, I provided four questions which I would have asked had I examined Nosenko: Did the KGB order Oswald to assassinate President Kennedy? Before November 1963, had you ever heard of Lee Harvey Oswald? Did the KGB order you to defect? Did the KGB instruct you what to tell the Americans about Oswald? (60) Note: My August 16, 23, 24, and 28 review of the reports, charts, and my blind chart analysis at the Select Committee on Assassinations' offices served only to strengthen the above opinions. 197 THE ANALYSIS OF JACK RUBY'S POLYGRAPH EXAMINATION Submitted by Richard O. Arther, President, Scientific Lie Detection, Inc., New York, N.Y., and director, National Training Center of Polygraph Science, New York, N.Y. Charles R. Jones, President, Polygraph Division, Lincoln M. Zonn, Inc., New York, N.Y. Benjamin F. Malinowski, President, Malinowski Polygraph Services, Inc., Savannah, Ga. --------------------------------- Report to the Select Committee on Assassinations U.S. House of Representatives Ninety-fifth Congress Second Session March 1979 (197) 198 CONTENTS Paragraph Introduction......................................................1 A polygraph examination...........................................3 Ruby's polygraph examination.....................................12 Interpretations of the polygraph examination.....................18 Selection of the panel...........................................24 Examination procedures...........................................30 Report of the polygraph panel....................................37 Crucial factors affecting the examination........................37 Loss of control..................................................50 Other factors....................................................58 Chart analysis...................................................95 (198) 199 INTRODUCTION* (1) On July 18, 1964, Jack Ruby voluntarily took a polygraph examination to test his truthfulness. Even though the Warren Commission disclaimed any reliance on the results of the test, (1) the committee believed that popular interest in such tests, as well as the possibility that new investigative "leads" might emerge, warranted a review of the examination. (2) The committee was specifically prohibited by its own rules (2) from using either failure or agreement to take a polygraph examination, or the results of a polygraph examination, as a basis for factfinding in any public hearing or report. Such restrictions did not apply, however, to a review of polygraph tests previously administered. The committee therefore engaged a panel of experts to review the Ruby polygraph examination to determine if it was properly conducted and analyzed. A polygraph examination (3) A polygraph examination records physiological responses to questions asked. The polygraphist attempts to design the examination in such a way that the truthful person will react to the control questions and the lying person to the relevant questions. (4) The test structure must be constructed so that it poses a threat to both the truthful and untruthful person. The polygraphist attempts to determine the "psychological set" of the examine. He tries to determine, by reading the physiological activity of the examinee in the polygraph charts, what questions or question areas pose the greatest threat to the examinee's well-being. A "psychological set" is "a permission disclaimed any reliance on the results of the test, (1) the son's fears, anxieties, and apprehensions, [which] are channeled toward that situation causing the greatest threat to the individual's well being. He will tune in on that which is of a greater threat, and tune out that of a lesser threat." (3) (5) Responses to questions are recorded on a polygraph chart, which consists of tracings produced by three different types of psychological reactions associated with the circulatory, nervous, and respiratory systems: (6) 1. The breathing pattern is recorded by means of a rubber tube placed around the person's chest. (7) 2. The Galvanic skin response is measured by placing the attach- ments on either the fingers or the palms. (8) 3. Changes in blood pressure, heart beat and pulse rate are obtained by a standard blood pressure cuff placed around the upper arm. ---------------------------------------- *Materials submitted for this report by the committee's polygraph consultants were compiled by HSCA staff members G. Robert Blakey and Whitney Warriss. (199) 200 (9) Questions are broken down into three categories: 1. Relevant--those pertinent to the investigation. 2. Irrelevant--hopefully meaningless, nonemotion-producing ones to get the person used to being- questioned and giving answers. 3. Control--nonrelevant to which it can be assumed the person will lie during the test. These provide a standard fox, comparing the responses to relevant questions. If a person reacts more to a proper control question than to the relevant questions, then he is considered to be truthful to the relevants. On the other hand, if he reacts more to the relevants than to the proper control question, he is considered to be lying to the relevants. (10) Relevant, irrelevant, and control questions are interspersed throughout the polygraph chart. The examination may consist of various series covering various relevant issues. Each relevant issue must be asked a minimum of two times in a series, but as many times as necessary to conclude that relevant issue successfully. Each series should have a minimum of two charts, but as many charts as necessary to conclude the relevant issues in that series successfully. (11) The procedure for a polygraph examination is as follows. The polygraphist first conducts a pretest interview, during which the test questions are read to the person exactly as they are going to be asked. It is vital that all questions be properly worded and discussed with the person. Then the actual test is conducted. Ruby's polygraph examination (12) Jack Ruby had repeatedly requested that he be examined with a polygraph, truth serum, or other scientific means to test his veracity.(4) In his testimony before the Warren Commission fission on June 7, 1964, he stated, "I would like to be able to get a lie detector test or truth serum of what motivated me to do what I did at that particular time * * *."(5) Chief Justice Earl Warren responded, * * if you and your counsel] want any kind of test, I will arrange it for you. I would be glad to do that, if you want it. I wouldn't suggest a lie detector test to testify the truth * * *.(6) Ruby repeated his request several times during his testimony. (13) Following numerous discussions among attorneys for Ruby and his family and other interested parties,(7) on July 18, 1964,(8) Ruby(9) took the examination signing a standard "Consent to Interview with Polygraph" form. (10) (14) The following persons were present during the examination, in addition to the expert, SA Herndon: (11) 1. Arlen Specter, Warren Commission counsel; 2. Clayton Fowler, Ruby's attorney; 3. William R. Beavers, Ruby's psychiatrist; 4. James Woods, FBI special agent; 5. E. L, Holman, chief jailer; 6. Odell Oliver, court reporter. (15) In addition to the above, Joe Touchill. Ruby's other attorney, and William Alexander, assistant district attorney for Dallas County, Tex., were present at each of the 13 pretest interviews. (12) Clayton Fowler, Ruby's attorney, did not want Assistant District Attorney 201 William Alexander to hear Ruby's answers and insisted that Ruby not answer questions until the actual tests had begun and Alexander had left the examination room. (13) In some instances, however, Ruby did answer the questions during the pretest stage. Special Agent Herndon had indicated that he preferred to have Ruby answer the questions during the pretest interview, as this was a generally accepted polygraph procedure. (14) (16) The polygraph examination lasted from 2:23 p.m. to about 9 p.m.(15) Ruby was asked a total of 101 questions, broken into 13 series. A pretest interview was conducted before each question series, at which time the questions were explained to Ruby. They were often rephrased for the actual tests. (17) The following are the relevant questions and answers from all 13 test groups comprising the Ruby polygraph examination: Question. Did you know Oswald before November 22, 1963? Answer. No. (16) Question. Did you assist Oswald in the assassination? Answer. No. (17) Question. Are you now a member of the Communist Party? Answer. No (18) Question. Have you ever been a member of the Communist Party? Answer. No. (19) Question. Are you now a member of any group that advo- cates the violent overthrow of the U.S. Government? Answer. No. (20) Question. Have you ever been a member of any group that advocates violent overthrow of the U.S. Government? Answer. No. (21) Question. Between the assassination and the shooting, did anybody you know tell you they knew Oswald? Answer. No. (22) Question. Aside from anything you said to George Senator on Sunday morning, did you ever tell anyone else that you intended to shoot Oswald? Answer. No. (23) Question. Did you shoot Oswald in order to silence him? Answer. No. (24) Question. Did you first decide to shoot Oswald on Friday night? Answer. No. (25) Question. Did you first decide to shoot Oswald on Saturday morning? Answer. No. (26) Question. Did you first decide to shoot Oswald on Saturday night? Answer. Yes. (27) Question. Did you first decide to shoot Oswald on Sunday morning? Answer. Yes. (28) Question. Were you on the sidewalk at the time Lieutenant Pierce's car stopped on the ramp exit? Answer. Yes. (29) 202 202 Question. Did you enter the jail by walking through an alleyway? Answer. No. (30) Question. Did you walk past the guard at the time Lieu- tenant Pierce's ear was parked on the ramp exit. Answer. Yes. (31) Question. Did you talk with any Dallas police officers on Sunday, November 24, prior to the shooting. Answer. No. (32) Question. Did you see the armored car before it entered the basement? Answer. No. (33) Question. Did you enter the police department through the door at the rear of the east side of the jail? Answer. No. (34) Question. After talking to Little Lynn, did you hear any announcement that Oswald was about to be moved. Answer. No. (35) Question. Before you left your apartment Sunday morning, did anyone tell you the armored car was on the way to the police department Answer. No. (36) Question. Did you get a Wall Street Journal at the Southwestern Drug Store during the week before the assassination? Answer. No. (37) Question. Do you have any knowledge of a Wall Street Journal addressed to Mr. J.E. Bradshaw Answer. No. (38) Question. To your knowledge, did any of your friends or did you telephone the FBI in Dallas between 2 or 3 a.m. Sunday morning? Answer. No. (39) Question. Did you or any of your friends to your knowledge telephone the sheriff's office between 2 or 3 a.m. Sunday morning? Answer. No. (40) Question. Did you go to the Dallas police station at any time on Friday, November 22,, 1963, before you went to the synagogue? Answer. No. (41) Question. Did you go to synagogue that Friday night. Answer. Yes. (42) Question. Did you see Oswald in the Dallas jail on Friday night? Answer. Yes. (43) Question. Did you have a gun with you when you went to the Friday midnight press conference at the jail. Answer. No. (44) Question. Is everything you told the Warren Commission the entire. truth ? Answer. Yes. 203 Question. Have you ever knowingly attended any meetings of the Communist Party or any other group that advocates violent overthrow of the Government? Answer. No. Question. Is any member of your immediate family or any close friend, a member of the Communist Party? Answer. No. (47) Question. Is any member of your immediate family or any close friend a member of any group that advocates the violent overthrow of the Government? Answer. No. (48) Question. Did any close friend or any member of your immediate family ever attend a meeting of the Communist Party? Answer. No. Question. Did any close friend or any member of your immediate family ever attend a meeting of any group that advocates the violent overthrow of the Government? Answer. No. (50) Question. Did you ever meet Oswald at your post office box? Answer. No. (51) Question. Did you use your post office mailbox to do any business with Mexico or Cuba? Answer. No. (52) Question. Did you do business with Castro-Cuba? Answer. No. (53) Question. Was your trip to Cuba solely for pleasure? Answer. Yes. (54) Question. Have you now told us the truth concerning why you carried $2,200 in cash on you? Answer. Yes. Question. Did any foreign influence cause you to shoot Oswald? Answer. No. Question. Did you shoot Oswald because of any influence of the underworld? Answer. No. (57) Question. Did you shoot Oswald because of a labor union influence? Answer. No. (58) Question. Did any long-distance telephone calls which you made before the assassination of the President have anything to do with the assassination? Answer. No. Question. Did any of your long-distance telephone calls concern the shooting of Oswald? Answer. No. Question. Did you shoot Oswald in order to save Mrs. Kennedy the ordeal of Answer. Yes. (61) Question. Did you know the Tippit that was killed? Answer. No. (62) 204 Question. Did you tell the truth about relaying the mes- sage to Ray Brantley to get McWillie a few guns? Answer. Yes. (63) Question. Did you go to the assembly room on Friday night to get the telephone number of KLIF? Answer. Yes. (64) Question. Did you ever meet with Oswald and Officer Tippit at your club? Answer. No. (65) Question. Were you at the Parkland Hospital at any time on Friday? Answer. No. (66) Question. Did you say anything when you shot Oswald other than what you've testified about? Answer. No. (67) Question. Have members of your family been physically harmed because of what you did? Answer. No. (68) Question. Do you think members of your family are now in danger because of what you did? Answer. [No response.] (69) Question. Is Mr. Fowler in danger because he is defending you? Answer. [No. response.] (70) Question. Did "Blackie" Hanson speak to you just before you shot Oswald? Answer. No. (71) Interpretations of the polygraph examination Dr. Beavers testimony. (18) The testimony of Ruby's psychiatrist, Dr. William Beavers, who was present during the examination, was taken by Specter immediately after the polygraph examination on July 18, 1964. (72) Beavers testified that he had examined Ruby 9 or 10 times and had diagnosed him as a "psychotic depressive."'However, Beavers stated that on the day of the examination, the "depressive element" had diminished, (73) aud that most of the time Ruby understood the questions and answered with an appreciation of reality. (74) The only questions that seemed to tap Ruby's underlying delusional state related to his opinion about the safety of his defence counsel or his family. (75) Beavers did canton, however, that he was an expert in the area of "interrelationships between mental illness and the polygraph." (76) Special Agent Herndon's testimony (19) On July 28, 1964, Special Agent Herndon testified before the Warren Commission regarding his interpretation of the Ruby polygraph. (77) Referring to Beavers' testimony, which Herndon had heard on July 18, 1964, Specter questioned him about the validity of a polygraph examination of a psychotic depressive person as described by Beavers. Herndon responded that an examination of person would be inconclusive or invalid in view of the fact that a psychotic individual is divorced from reality, and the tracings of his polygrams could not be logically interpreted. (78) 205 (20) Specter then questioned Herndon about his interpretation of the polygraph examination based on the hypothesis that Ruby was in fact touch with reality during the examination and understood the na- ture of the questions and the quality of his answers. Herndon testi- fled that, assuming Ruby was mentally competent, and interpret the charts as indicating that there was no deception in Ruby's responses to the relevant questions in the examination, that Ruby answered all relevant questions truthfully. (79) During later testimony, when Herndon was questioned about specific questions, he again was careful to qualify his interpretation with the assumption that Ruby was of sound mind. Herndon made it clear that he would find the results inconclusive and the examination inval(id)in the event Ruby was not of sound mind. (80) (21) Herdon did mention four factors that he believed should be considered in the overall evaluation of Ruby's polygraph examination. The factors involved the prior extensive interrogation of Ruby, the time elapsed since Ruby shot Oswald, the number of persons present during the polygraph examination, and the number of relevant test questions asked. Herndon stated: Mr. SPECTER. Do you have anything to add which you think would be helpful to the President's Commission? Mr. HERNDON. Yes. I would like to make a few additional comments with regard to this polygraph examination, in view of the fact that it was somewhat unique and unusual. I think these factors should be somewhat considered in the overall evaluation of the polygraph examination. First of all, Ruby has obviously been extensively interviewed by law enforcement officers and by the Commission and other people, and there has been a considerable length of time lapse since the time that the instant offense occurred of him shooting Oswald. These factors of length of time and considerable previous interrogation would tend to detract or negate any specific or definite conclusion that could be rendered with regard to the polygraph examination. The fact that there were other personnel in the room would tend to negate a valid polygraph technique. However, here again I did mention that this did not appear to bother Mr. Ruby. But it should be considered and made a matter of record. One other point I would like to mention, and that is the large number of relevant questions asked Mr. Ruby during this particular examination. This is not general standard procedure. However, I realize that the President's Commission wanted to cover many facets, and that it was mutually agreed upon that we would ask the questions that the Commission had originally drawn up for this particular interrogation. In normal polygraph procedure it is usual to keep the relevant. questions down to perhaps several specific critical relevant questions and work strictly on those, and in this particular examination we had a large number of relevant questions to ask. I think these are all factors that should be considered in the overall eva]nation of Mr. Ruby's polygraph examination. Mr. SPECTER. Thank you very much, Mr. Herndon. (81) 206 FBI memoranda (22) Two FBI memoranda address the Bureau's interpretation of Ruby's polygraph. The first, dated July 20, 1964, (82) states that a preliminary review of the charts indicated that Ruby was not. deceptive when denying that he knew Oswald or that he was involved in any conspiracy. The memo went on to note that this interpretation did not conflict with any of the FBI's prior investigations. The memo did caution, however, that if in fact Ruby had a "psychotic" personality, the test results should be considered inconclusive and not be relied on. The second memorandum, dated July 22, 1964, (83) repeated the same conclusion. The Warren Commission's conclusion (23) The Warren Commission stated in its report that it did not rely on the results of the Ruby polygraph examination in reaching its conclusions.(84) The commission noted that it had merely granted Ruby's request for such an examination. It published the transcript of the examination, as well as the transcript of the deposition of the FBI polygraph expert who administered the test. Selection of the panel (24) In August 1977, the committee decided to convene a panel of experts with no prior affiliation with the Kennedy (or the King) * case to review the polygraph examination. Recommendations for panel membership were invited from Walter F. Atwood, executive director of the American Polygraph Association in 1976, and Charles R. Jones, vice president of the American Polygraph Association in 1978. (25) They suggested nine people who were asked to provide resumes; additional information was sought later. Each was also asked to provide a list of the leading polygraphists. (26) The committee interviewed 19 prospective panel members and chose 3: (27) Richard O. Arther--B.S. with honors, in police science, Michigan State University, 1951; M.A. in psychology, Columbia University, 1960. Arther has been in private practice in New York City since 1953. He rounded Scientific Lie Detection, Inc., cofounded the National Training Center of Polygraph Science. He has taught at Brooklyn College, Seton Hall University, the John Jay College of Criminal Justice, and the Graduate School of Public Administration of New York University. He has authored over 200 professional articles and two books. Arther is a member of the Academy of Certified Polygraphists and the American Polygraph Association. (28) Charles R. Jones--B.S. in education (major in social science); completed National Training Center of Polygraph Science in 1959. Jones has been an instructor at the police training school in Charleston, W. Va., and currently teaches at the Zonn Institute of Polygraph, Inc., in Atlanta, Ga. He joined the Lincoln M. Zonn firm in 1961. Jones is a member of the American Polygraph Association and was elected vice president in 1976. (29) Benjamin Frank Malinowski--retired Army warrant officer, with a career in criminal investigation and polygraph examinations. -------------------------------------- *The same panel was to conduct an analysis of the James Earl Ray polygraph examinations. 207 He has been an instructor at the U.S. Army Military Police School, Fort Gordon, Ga. He attended the National Training Center of Polygraph Science in 1966. From 1967 to 1969 he was an operations officer with the Southern European Criminal Investigations task force. In 1975, he founded the Malinowski Polygraph Service. He is a member of the American Polygraph Association, and a former director of the Georgia Polygraph Association; twice president of the Georgia Polygraph Association; author of numerous articles on polygraph and criminal investigations, and formerly president of the Zonn Institute of Polygraph. He is also a nationally recognized speaker on polygraph and criminal investigations. Examination procedures (30) On March 6, 1978, a letter was sent to each panel member informing him of the materials available relating to the Ruby polygraph. They were: 1. The original polygraph charts. 2. A stenographic transcript of the entire examination, including the pretest and posttest interviews. 3. Testimony of Dr. Beavers, given before the Warren Commission, concerning Ruby's medical condition ,at the time of the examination. 4. Testimony of FBI Special Agent Herndon, the FBI polygraph examiner, before the Warren Commission. 5. Expert medical testimony given at Ruby's trial. (31) Each panel member was asked to review the list and inform the committee if they required all items or additional material. Each responded that the first four items were necessary and that the medical testimony at Ruby's trial would not be required. On May 19, 1978, copies of the materials other than the medical trial testimony were sent to each expert. (32) The procedures were that: (1) Each polygraphist would conduct an independent examination of the materials (2) the panel would then meet to discuss each member's findings; (3) a final joint panel report would be prepared and submitted to the select committee. (33) The experts were asked to focus on the following major areas: 1. The circumstances surrounding the administration of the examination. 2. Any problems created by the medical condition, age, mental stability, et catare, of the subject. 3. The procedure/technique used by the expert in administering the examination. 4. The analysis of the charts. (34) The experts were told, however, that they should not feel confined by the above areas and should comment on any factor they considered relevant. (35) On June 22, 1978, the three panelists and two committee staff members met at the Algonquin Hotel in New York City. The National Archives agreed to have the original charts taken to this meeting. At this time the experts reviewed the original charts and discussed the polygraph examination. The panel was unanimous in its evaluation and agreed that, Arther would be responsible for writing the panel's Ruby report, subject. of course, to the review and approval of the other two panel members. (85) 208 (36) The panel conducted its review using the state of polygraph technology in 1964. However, since the panel's review involved basic polygraph principles, the comments and conclusions are still timely. REPORT OF THE POLYGRAPH PANEL Crucial factors affecting the examination (37) The panel noted the four factors mentioned by Herndon as having a detrimental effect on the examination: The time elapsed since the shooting.; Ruby's extensive prior interrogation; the many people present during the examination; and the great number of relevant questions asked. (86) (38) The panel believed these factors had a serious negative impact on the validity and reliability of the polygraph examination. Because Ruby had been extensively interrogated previously, Herndon should have been sure that the polygraph examination was very carefully conducted. (39) When first approached by the Commission, Herndon immediately should have explained the polygraph's limitations. He should have refused to compromise the validity and reliability of the polygraph procedure by letting it become yet another interrogation of Ruby. (40) Herndon himself considered the procedure to be more an interrogation than a polygraph examination, as seen in his testimony before the Commission with regard to test series 9: Mr. HERNDON. Yes, there was at this point in the interrogation. Realizing the Commission had a large number of questions they wanted to ask, it was decided at this point, in view of the fact that we had asked the main critical questions, to proceed with what I call direct interrogation, that is that each and every one of the questions asked is a relevant question, and that there are no irrelevant questions or control questions asked. (87) And again, discussing test series 9A, he testified: Mr. HERNDON. This was done in order to save time inasmuch as the interrogation was becoming rather lengthy at this point, and Mr. Specter indicated he was anxious to proceed and to complete the rest of the questions that we had agreed upon with all those parties that were interested in this interrogation. (88) (41) Note that in the above quotes Herndon uses the term "interrogation" four times, but not once does he use the term "polygraph examination." If the events of July 18 were considered an interrogation rather than a polygraph examination, the panel would be far less concerned with what it felt were gross abuses of basic polygraph principles. However, since Herndon rendered his opinions as a "polygraph examine" the panel evaluated Ruby's charts as a polygraph examination. (42) The panel was also very concerned about the number and movement of people in the examination room. During the pretest interviews, as many as 10 persons were present. Two left for the testing 209 phase, returning for the next pretest interview. Since there was a series of 13 pretests and then tests, such comings and goings certainly must have caused distractions. (43) Herndon himself testified: Mr. HERNDON. Normally during a polygraph examination the only ones in the room are the examinee and the examiner, and during Bureau proceedings we usually have another agent in the room out of sight that takes notes. It is considered an undesirable factor to have many people present in the room during a polygraph examination, particularly if these people are involved in any way in the case, such as the defendant's attorney or someone who has a personal and keen knowledge in the proceedings. In this particular instance, it appeared to me that Mr. Ruby divorced the presence of these people from his mind during his response to the questions. However, it should be considered a factor which is one that could tend to negate a valid conclusion with regard to chart interpretation. (89) (44) The panel believes the presence of eight persons in the examination room seriously impaired the examination. Any momentary distraction during the examination could cause the examinee to react, thereby recording a "lie" reaction on the polygraph chart. Herndon could well think this reaction was a true reaction to a lie, especially when reviewing the charts at a later time. Further, the panel found that Herndon never repeated a relevant question. The possibility of uncorroborated reactions which are false becomes very crucial in the evaluation of the Ruby polygraph examination. (45) Herndon should have insisted, long before the date of the examination, that the standard procedure be followed whereby only the polygraphist and the person are in the room. If others had a need to observe the examination, then a room with a one-way mirror, a sound system, and perhaps a recording device could have been used--all standard procedures since the 1930's. A recorder might also have eliminated the need for the presence of a reporter in the examination room. A recorder generally provides a more accurate record. The Dallas Police Department had available a specially prepared and equipped room which would have allowed for a much more professional and conducive atmosphere. (90) (46) A third factor the panel finds impaired the Ruby polygraph examination concerned the number of relevant test questions asked. The panel members believe it showed total disregard of basic polygraph principles. (47) The crux of every polygraph examination is the number of test questions and how they are worded. When the Ruby examination was conducted, the primary textbook on the subject was "Lie Detection and Criminal Interrogation," by Fred E. Inbau and John E. Reid (3d ed., 1953). This book recommends three relevant questions, since the more a person is tested, the less he tends to react when lying. That is, sooner or later, liars become so "test-tired," they no longer produce significant physiological reactions when lying. One panel member, Arther, said that in his 27 years of experience he had never heard of 210 polygraph examination with more than 17 relevant questions. Yet, in the Ruby examination, Herndon asks some 55 relevant questions. As Herndon himself stated: In normal polygraph procedure it is usual to keep the relevant questions down to perhaps several specific critical relevant questions and work strictly on those. (91) (48) Further, the panel could see no need for the vast majority of the relevant questions. It considered most to be trivial in comparison with the major issues on which Herndon should have concentrated. For example, the following trivial and poorly worded relevant questions were asked: 1. Did you get a Wall Street Journal at the Southwestern Drug Store during the week before the assassination? 2. Did you go to the Dallas police station at any time on Friday, November 22, 1963, before you went to the synagogue 3. Did any close friend or any member of your immediate family ever attend a meeting of any group that advocates the violent overthrow of the Government? (92) (49) The panel concludes that Herndon should have insisted that the total number of issues covered be reduced to no more than before. The panel suggested, for example, that only the following four relevant test questions should have been asked to cover the critical issues (Herndon did ask questions similar to three of the areas): Before last November 22, did you ever hear the name of Lee Harvey Oswald? Did you murder Oswald to silence him? Did anyone instruct you to murder Oswald? Did you ever talk with Lee Harvey Oswald? (93) Loss of control (50) Numerous instances in the transcript of the Ruby polygraph examination indicate that Herndon completely lost control over the examination. The problem most often stemmed from the ad hoe participation of the observers in the conduct of the polygraph examination. (Of course the panel found the number of observers itself to be detrimental to the examination.) (51) As an example the standard pretest procedure is to ask the person each question and allow for discussion and a response. This is done before any of the components are attached to the examinee. Herndon stated his intention to proceed in this manner, but upon objection from Ruby's attorney, Clayton Fowler, Herndon acquiesced, abandoning this most important aspect of the pretesting phase and disregarding an important polygraph principle. The applicable part of the transcript follows: Mr. HERNDON. In other words, I am going to tell you what the question is going to be and you shall feel free to answer it "yes" or---- Mr. Fowler. Excuse me. sir. Mr. Herndon. Certainly. Mr. Fowler. At this time, Jack, I request that in view of the fact that you're not hooked up, that you do not answer the 211 question and reserve those until such time as you will be on the machine. Mr. RUBY. That's fine. Mr. HERNDON. Then, we will just discuss the questions. Mr. RUBY. Do it to your advantage, may I add. Mr. HERNDON. I generally prefer in my practice with the polygraph to have the gentleman answer the question so that he knows he has already answered it, and as a matter of record, he knows that that question is coming along. Mr. RUBY. Please let me do it, will you? [Addressing Mr. Fowler.] Mr. FOWLER. [No response.] Mr. HERNDON. I will bow to whatever Mr. Specter or counsel wants to do in this regard. Mr. RUBY. Fowler, I hate to dispute with you, but let me do it this way? Mr. FOWLER. Well, Jack, again, Mr. Alexander is here and again I tell you this--that the answers to some of these ques- tions could be absolutely very detrimental to you. Mr. RUBY. They can't. Mr. FOWLER. I'm talking about from a legal standpoint. Now, morally, I know how you feel and you want to do the best you can for the commission. Mr. RUBY. I will. Mr. FOWLER. But by the same token, this gentleman over here [referring to Mr. Alex Ruder] represents the State, who at this time is not representing you. Now, if we could allow Mr. Alexander to have the benefit of the nature of the questions, with the exception of the answers--if this it what Jack wants--but I do not want Mr. Alexander to have the benefit of the answers. Mr. SPECTER. The test may be conducted either way. As Mr. Herdon has explained, he has a slight preference to have the answers, but the ultimate decision on that is up to Mr. Ruby and his counsel. The commission will proceed in either manner. Mr. RUBY. It's unfortunate that my attorney, Mr. Fowler, don't see as I do. I would like to give every cooperation without the slightest fraction of interference. That's why I requested that. You won't let me do it that way, huh, Fowler? Mr. FOWLER. I'm requesting that you do not, Jack. Mr. HERNDON. It will be no problem. (94) (52) Other examples of Herndon's loss of control abound. For example, on one page of the transcript. he makes only two short statements; (95) at another point, a discussion by the observers about one question occupies almost six pages and includes an argument between Ruby and his attorney, Fowler, about who should be present in the room. (96) At other points, Ruby is reminded by Fowler that he could be convicted of first-degree murder by telling the truth and that he should not even be taking the polygraph examination. And at still another point, Herndon seeks the advice of Warren Commission attorney Specter about the phrasing of a question. (97) 212 (53) A good example of an objectionable result that occurred because of Herndon's loss of control takes place as follows. Just before test series No. 4, Ruby's responses were very erratic. He appeared to have "gone to pieces." Herndon later attributed this to fatigue, citing this as "the first series where Mr. Ruby tends to show a little fatigue." (98) (54) However, just before that series had started, Ruby had had a private conversation from 4:13 to 4:15 with another of his attorneys, (99) whom Ruby previously had not wanted in the examination room, as shown by this: Mr. RUBY. Did you get your pants sewed up, Joe? Mr. TONAHILL. It went through to my leg. Mr. RUBY. That was a pretty rough brawl we had, wasn't it, Joe? Mr. TONAHILL. Yes. Mr. RUBY. Joe, I'd appreciate it if you weren't in the room. Can I ask you to leave, Joe? Mr. TONAHILL. I'll be glad to leave, if you want me to, Jack. Mr. RUBY. As a matter of fact, I prefer Bill Alexander to you, you're supposed to he my friend. Mr. TONAHILL. Let the record show that Mr. Ruby says he prefers Bill Alexander being here during this investigation, who is the assistant district attorney who asked that a jury give him the death sentence, to myself, who asked the jury to acquit him, his attorney. (100) (55) Ruby then had two off-the-record conversations with Alexander-from 4:15 to 4:18 and from 4:22 to 4:25, (101) followed by still another extremely long argument as to the wording of just one test question, with five people taking part in the discussion: (102) "Were you in the Dallas Police Department jail at the time Lieutenant Pierce's car drove out of the basement?" (103) (56) The panel questioned Herndon's conclusion that it really was fatigue that caused Ruby to "go to pieces" on this particular test, believing it might have been due either to something said during the three private conversations or to the argument over the wording of that one question. Perhaps it simply was the chaotic nature of the entire situation. (57) The panel believed that the participation of the observers and the various asides never should have been allowed by Herndon. The panel concluded that Ruby was probably distracted, both mentally and physicaly, making a difficult examination even more difficult to conduct successfully. Other factors (58) In addition to the factors discussed above which impaired the Ruby polygraph examination, the panel concluded that 10 additional factors, of perhaps less importance, further reduced the validity and reliability of the examination. These are as follows: (59) 1. It is generally agreed that, the best time to examine is in the morning, because then the great majority of persons are both physically and mentally "fresh." As the day progresses, a person normally tires. Since the polygraph mainly records physical change induced by mental stimulation, a tired person does not react to stimulation as well 213 as a rested person does. Although Ruby most likely was a night- oriented person as a result of his occupation as a nightclub owner, by July 18, 1964, normal prison routine no doubt had changed his orienta- tion. The panel therefore concluded that the examination should have started early in the day, perhaps around 8 a.m. As it was, the exam- ination started at 2:23 p.m., with the first test beginning at 3:10 p.m.(104) (60) 2. When administering an extremely difficult examination, most experts advocate reexamination on a later date to check the reliability of the first examination, that is, will the same reactions be obtained on the reexamination? Ruby was never given a second polygraph exami- nation, nor is there any indication that one was ever considered. After reviewing the charts, each panel member believed strongly that a reexamination was absolutely essential for at least three reasons: (61) a. It is a basic and commonly accepted polygraph procedure. (62) b. Herndon did not repeat relevant questions, thereby provid- ing no possible corroboration of the results. (63) c. All of the adverse factors working against the orderly conduct of the examination made the results of the examination suspect, at best. (64) 3. The panel concluded that the polygraph instrument was either improperly adjusted, or defective, or both. It made three trac- ings, two of which are so totally inadequate that they appear to be defective. The breathing tracing is particularly poor, either because the sensitivity was maladjusted or possibly because the pneumograph tube was not properly placed on Ruby. The amplitude of the breathing tracing is not even minimally acceptable in any of the 13 tests. The panel found this to be a constant handicap in analyzing this extremely important tracing and interpreting the charts. Sufficient amplitude is critical because the polygraphist looks for changes in the breathing pattern. Often such changes are minute and simply do not appear when the amplitude is small to begin with. (65) The panel found the galvanic skin response (GSR) tracing to be of minimal help in analyzing Ruby's charts. The main problem with the GSR in the first session (before the break) is a lack of sen- sitivity due to Herndon's setting the sensitivity at one-fourth of max- imum. He decreased it to one-fifth for the third series of questions. The panel noted that it should have been tried at a maximum sensitivity prior to the first test, where probably it should have remained for the entire examination. Had the sensitivity been higher, the polygraph probably would have produced an adequate tracing, that is, one that the panel could analyze. (66) The panel could provide no explanation for why Herndon de- creased the sensitivity for the third series. In fact, generally recognized principles in 1964 called for the sensitivity to be continually increased. (67) After the break, the examination commenced with series 5 through 11, with the sensitivity set at one-fifth of maximum. (68) The panel concluded that during this entire session, the GSR was completely defective. At best the polygraph appeared to be in extremely poor condition. In an examination of this importance, a backup polygraph should have been available and in the panel's view, should have been used. The examination should have been stopped until another polygraph could be obtained. 214 (69) 4. Herndon's definition of a "control" question goes far beyond the generally recognized definition, as discussed in the leading book of the day by Inbau and Reid. The "control" question, developed by Reid in 1943, is one similar but unrelated to the crime being investigated to which the expert knows the correct answer and to which the person will probably lie. If the person's reaction to a properly worded control is more pronounced than to the relevant questions, he is considered to be truthful. On the other hand, if his reaction to the relevant questions is more pronounced, he is considered to be lying to the relevant questions. (70) If the control questions are properly worded, it is very possible that a person lying to the relevant questions will appear to be truthful. (71) Herndon's control questions were not correctly worded. He defined a "control" question as one to which the person will have some emotional response. (105) Thus, he used such controls as: 1. Have you ever been arrested? (106) 2. Are you married? (107) 3. While in the service did you receive any disciplinary action? (108) 4. Have you served time in jail? (109) 5. Did you attend the synagogue regularly? (110) (72) It is obvious that not one of the above questions is a control, as defined by Inbau and Reid. For example, to the question, "have you ever been arrested?", Ruby answered "yes." Therefore, it is not a lie, yet Herndon considered it to be a control question. (111) (73) Further, Herndon violated a basic rule that surprise questions should never be used as controls. For example, while asking a series, he says, during the test, "have you ever been known by another name? Don't answer that question. Skip it. Just sit and relax." (112) (74) Such talk by the expert should automatically prevent this question from being used in the chart analysis. yet Herndon uses it as a control. He testified: "The only significant change physiologically during series No. 2 was in Mr. Ruby's response to the question, "Have you ever been known by another name?," portrayed by an increase in his blood pressure." (113) (75) Such a procedure can easily lead to a mistake, particularly in indicating a liar to be truthful. In fact, if one wants to generate a truthful response on the cart when testing a liar, one could ask a suprise question, then immediately give extensive instruction regarding it, and thereafter evaluate it as a control question. In such a situation, at least 95 percent of the liars will give a more intense physiological reaction than they will to the relevant question to which they are lying. (76) 5. What Herndon considers to be irrelevant questions often do not meet the criteria for an irrelevant question. The generally accepted definition of an irrelevant question is a meaningless, nonemotional question which the plygraphist knows the person will answer truthfully, e.g., "Do you live in the United States", or "Right now are you in Texas?" (77) It was difficult for the panel to determine if Herndon considered certain questions to be irrelevants or controls. In fact, he himself confused their distinction. For example, question 4 in series 3 is officially listed as an irrelevant ("Are you married?"), yet Herndon used it as one of his control questions.(114) 215 (78) Following are several examples of irrelevant questions, as indicated on Herndon's question sheets, which the panel concluded were improperly classified. The panel found these questions to be more relevant, at times, to the important issues than the questions Herndon had listed as relevant. 1. Is your last name Ruby? (Originally his name was Rubenstein, and Herndon asked this question even after being told that Ruby changed his name from Rubinstein.) (115) 2. Did you take any medication this morning? 3. Have you answered these questions truthfully? 4. Are your parents alive? (Both are dead, and after his father died Ruby went to the synagogue "consistently for 11 months, morning and evening.") (116) 5. Are you tired? 6. Do you intend to answer the questions truthfully? 7. Were you at one time employed by a union? (There was also a relevant question, "Did you shoot Oswald because of labor union influence?") (117) 8. Is everything you told the Warren Commission the entire truth? (79) 6. It is customary to repeat every question at least on a second test. This is done in order to establish the consistency (reliability) the polygraph reactions. This was not done in the Ruby examination. Therefore, there was no way for Herndon to establish the reliability of the relevant questions. (80) Hence, the possibility that a "lie reaction" to a control was caused by something other than a lie remains an open issue. This is particularly important because there were so many possible distractions in the examination room. (81) 7. Between tests, a polygraphist should not tell a person if the tracings indicate truthful or lying responses to the relevant questions. This is particularly important in case a liar has some method of "beating the lie detector." If he believes he is coming across as truthful, he is reassured that his method is working. Thus, he will feel less uneasy when he lies, producing less dramatic reactions. (82) In spite of this, after completing the first series, Herndon told Ruby: "Mr. Ruby, there are two questions I want to ask you about on our first series." At this point he discussed only the questions having to do with Ruby's middle name and the question having to do with whether Ruby had ever been arrested. Herndon did not mention the relevant questions, which could easily have led Ruby to believe that he had "passed" the test in regard to the relevant questions. (118) (83) Herndon finished the discussion of series 1 with the comment: "Mr. Ruby, you are now a veteran of the first series. You did real well. You cooperated very fine." (119) (84) Such statements could easily be interpreted by Ruby as meaning that he seemed to be truthful (to the relevant questions), especially when Herndon stated, "You did real well." (85) If Ruby had lied on the first test, he would have had good reason to believe he had beaten the polygraph. Such knowledge certainly would have reduced his fear of lying, hence his lying reactions would have been reduced in subsequent questioning. (86) And again, just as the first series is ending (prior to the break at 4:45 after series 4, Herndon stated:"You've done very well thus far, Mr. Ruby, as far as cooperating on the examination." (120) 216 (87) 8. A great deal of thought and preparation is necessary to conduct a quality polygraph examination. When a case is complicated or the examination conditions adverse, more preexamination preparation is necessary. (88) In the panel's opinion, Herndon appeared largely unprepared to conduct the Ruby examination. Herndon testified that he knew the issues the Warren Commission wanted covered. (121) However, it appeared that all questions were not prepared in written form before the day of the examination. For example, as the first phase of the examination was being completed, Herndon said: "We will have to prepare some more questions." Specter: "May the record show that Mr. Alexander and Mr. Tonahill are now back in the room, and we are going to take a brief recess." (122) The "brief recess" lasted 1 hour and 40 minutes, during which time Ruby apparently was left in the examination room. (123) (89) 9. The panel concluded that Herndon often used techniques in conducting the polygraph examination which did not conform to generally recognized principles of polygraphy. An example is test series 3A, which apparently was a "searching peak-of-tension test." A searching peak-of-tension test usually contains six or seven logical questions on the same issue. The polygraphist does not know which one is actually true. It is hoped that the liar will give a lying reaction to the appropriate question, thus permitting the expert to, learn information not previously known. This test is usually given to locate loot and/or weapons, learn the names of accomplices, determine the amount of money embezzled, et cetera. (90) The panel found the wording of the basic question in this series--("When did you first decide to shoot Oswald?")--to be very poor. This question ignored the possibility that Ruby might have been ordered to murder Oswald. The panel a]so found other choices to be poor. For example, the possibility that Ruby may have decided to shoot Oswald on the previous Friday night or the next Saturday afternoon were not even asked. (91) 10. It is generally agreed that the more a person is tested, the less responsive he becomes. If a liar is tested enough times, sooner or later, his reaction to lies will be no more intense than to control and relevant questions, lie therefore will appear truthful when lying. For this reason, the great majority of the recognized polygraph techniques limit the number of test groups to five or less, with no more than two different series of questions. Most call for the entire examination to be concluded within 2 hours. Panel member Richard Arther, for example, uses just one series of four relevant questions, asked in three separate test groups. (92) The Ruby examination consisted of 13 groups of questions, with the actual examination starting at 2:23 p.m. (124) and ending at 8:59 p.m. (125) Even though there supposedly was a break of 100 minutes, the testing should never have been resumed that day. (93) Herndon himself recognized this: Mr. SPECTER. Is there any overall limitation on the amount of time that a person can appropriately take a polygraph examination? Mr. HERNDON. Yes; there is a limitation. Certainly if a person is interviewed with polygraph at great length, in 217 due time he is bound to become desensitized to the technique. In other words, the pressure on his arm and the technique itself becomes less valid as the increase in time proceeds. Mr. SPECTER. Did Mr. Ruby ever become desensitized to the technique? Mr. HERNDON. I believe in the last series of the first session, which I believe is series 4, Mr. Ruby showed some indications of becoming fatigued and displayed some tiredness in the charts. Also, I might add in the later phase of the examination, in the latter series, there was some indication that he was approaching this desensitization that I have mentioned before. (126) (94) The panel concluded that the Ruby examination was far too long. Chart analysis (95) The panel concluded that the Ruby polygraph examination was probably invalid and unreliable. As discussed above, the panel found serious flaws in the examination procedures. The questions were especially poorly worded. The polygraph instrument itself was either incorrectly adjusted or defective in its operation. The panel could render no opinion regarding the examination results. (96) Of the 13 test groups, the first and second are perhaps the most valid in that they were conducted when Ruby was still "fresh?" Because of the importance of the relevant questions in these two tests, the panel has briefly summarized its opinion about them. (97) The relevant questions on the first series and Ruby's answers were: 1. Did you know Oswald before November 22, 1963? Answer. No. 2. Did you assist Oswald in the assassination? Answer. No. (98) Herndon concluded from his analysis of the charts that Ruby was truthful in answering these two relevant questions. He arrived at this conclusion by comparing Ruby's response to the control question (Have you ever been arrested? Answer: Yes. (99) As previously noted, the panel believed this to be an extremely poor control question. (100) Herndon testified that Ruby's physiological response to this control question was recorded on the charts in terms of a "noticeable rise in his blood pressure." (127) The panel took issue with this conclusion because the rise in blood pressure occurred at least 7 seconds ater Ruby answered. A response normally never occurs this long after the question. The typical reaction, would be in 1 or 2 seconds. Further, the panel noted that at the point of the rise in blood pressure, Herndon indicated on the chart (as "MF") that Ruby moved his feet. The panel believed that the rise in blood pressure most likely was caused by Ruby's movement and not his physiological reaction to the "control" question. This conclusion is corroborated by the fact that Ruby's breathing remained relaxed at the time of the rise in blood pressure, and the Galvanic skin response showed no reaction. (101) In fact, the reactions to the preceding question--(Did you assist Oswald in the assassination?)--showed the largest valid GSR reaction in test series No. 1. In addition, there is a constant suppres- 218 sion of breathing and a rise in blood pressure at the time of this crucial relevant question. From this test, it appeared to the panel that Ruby was possibly lying when answering "no" to the question, "Did you assist Oswald in the assassination ?" This is contrary to Herndon's opinion that Ruby was truthful when answering that question. (102) The relevant questions on the second series and Ruby's answers were: 1. Are you now a member of the Communist Party? Answer. No. 2. Have you ever been a member of the Communist Party? Answer. No. (103) Herndon concluded that Ruby was truthful when answering these two questions. He testified that the only significant physiological change noted occurred in response to the question, "Have you ever been known by another name?" The response identified by Herndon was a rise in blood pressure. (128) However, Herndon stated that Ruby later said he was confused on how to answer the question because he had changed his name from Jack Rubenstein years before. Herndon testified that other variations in the breathing tracing were caused by Ruby's hesitating to answer some questions due to their length. (129) (104) The panel noted that according to the transcript of the examination, Ruby did not answer the question about his having another name. Herndon told him not to answer because they had not reviewed it during the pretesting phase.(130) The panel concluded that Ruby's reaction was simply a false reaction to Herndon's unorthodox instruction after he asked the question. On the other hand, the panel noted large rise in blood pressure in response to the question, "Have you ever been a member of the Communist Party?", to which Ruby answered, "no." (105) This question also evoked by far the most dramatic breathing reaction. Although Horndon claimed that the only variation in breathing in this series is caused by the length of the questions, this was certainly a short question, and it is much more likely he was referring to the other questions.(131) (106) In fact, in regard to the question, Are you Communist Party?", Herndon stated, "there was no significant physiological change."(132) However, Herndon himself apparently wrote on the chart on this question, "slight suppression," which indicates a specific emotional change and one which is an excellent indicator of lying. (107) It is interesting to note that, during the entire first testing session this is the only place where Herndon wrote on the chart anything having to do with the breathing, except on series 4, when he wrote as general comment, "Breathing irregular." (108) In summary, the panel strongly disagreed with Herndon's opin- ions, and specifically with series 1 and 2, as discussed above. The panel concluded that the "lie" reactions on these two tests occurred on ques- tions different from those suggested by Herndon. Based on its analysis of the charts themselves, and not considering the negative factors feeting the veracity of the examination, the panel could not form an opinion that Ruby told the truth when answering "No" to the four relevant questions asked on test series 1 and 2. On the contrary, the panel found more indication that Ruby was lying in response to these four questions. 219 (109) It is emphasized by the panel, however, that no opinion could be rendered on the validity of this examination or the reliability of the results for the numerous reasons discussed in this report. REFERENCES (1) Report of the President's Commission on the Assassination of President Kennedy, p. 808 (hereinafter cited as the Warren Report). (2) Procedural rules of the House Select Committee on Assassinations, rule 7.2 (a). (3) From the curriculum of the U.S. Army Provost Marshal General Polygraph School, Fort McClellan, Ga. (4) Warren Report, p. 807. (5) Warren Report, p. 807; hearings before the President's Commission on the Assassination of President Kennedy (1964), vol. 14, p. 181 (hereinafter cited as Warren Commission hearings). (6) Ibid. (7) FBI teletype, to director from Dallas, July 15, 1964, file No. 44-240161762; letter from Hoover to Rankin, July 16, 1964, FBI file No. 44-24016-1765; FBI teletype, to director from Dallas, July 25, 1964, FBI file No. 44-24016-1797; Warren Report, p. 808. (8) Warren Report, p. 808; FBI teletype to director from Dallas, July 18, 1964, file No. 44-24016-1801. (9) Warren Commission hearings, vol. 14, p. 515. (10) Consent to Interview with Polygraph, signed by Jack Ruby, July 18, 1964, FBI file No. 44-24016-/821. See Warren Commission hearings, vol. 14, p. 515. (11) Id. at 511. (12) Id. at 514. (13) Id. at 514. (14) Id. at 518. (15) Id. at 511, 569. (16) Id. at 523. (17) Ibid. (18) Id. at 526. (19) Ibid. (20) Ibid. (21) Ibid. (22) Id. at 534. (23) Ibid. (24) Ibid. (25) Id. at 536. (26) Ibid. (27) Ibid. (28) Ibid. (29) Id. at 540. (30) Ibid. (31) Ibid. (32) Ibid. (33) Id. at 546. (34) Id. at 547. (35) Ibid. (36) Ibid. (37) Id. at 551. (38) Ibid. (39) Ibid. (40) Ibid. (41) Id. at 553. (42) Ibid. (43) Ibid. (44) Ibid. (45) Ibid. (46) Id. at 556. (47) Ibid. (48) Ibid. (49) Ibid. (50) Ibid. 220 (51) Id. at 560. (52) Ibid. (53) Ibid. (54) Id. at 560-561. (55) Id. at 561. (56) Ibid. (57) Ibid. (58) Ibid. (59) Ibid. (60) Ibid. (61) Ibid. (62) Ibid. (63) Ibid. (64) Ibid. (65) Ibid. (66) Id. at 563. (67) Ibid. (68) Ibid. (69) Ibid. (70) Ibid. (71) Ibid. (72) Id. at 570. (73) Id. at 571. (74) Id. at 572. (75) Ibid. (76) Id. at 575. (77) Id. at 579. (78) Id. at 582. (79) Id. at 586. (80) Id. at 587. (81) Ibid. (82) FBI memorandum, to Conrad from Jones, July 20, 1964, file No.44- 24016-1807. (83) FBI memorandum, to Conrad from Jones, July 22, 1964, file No.44- 24016-1827. (84) Warren Commission Report, p. 816. (85) HSCA Outside Contract Report, June 22, 1978, JFK Document No. 006748. (86) Warren Commission hearings, vol. 14, p. 598. (87) Id. at 595. (88) Id. (89) Id. at 583. (90) In July 1964, Paul Bentley was the chief polygraphist, Dallas Police Department. During the summer of 1978, Bentley confirmed to panel member Arther that his properly equipped room would have been made available had anyone requested it for Ruby's examination. (91) Warren Report at 598. (92) Id. at 551-556. (93) Id. at 559-561, inter alia. (94) Id. at 518. (95) Id. at 528. (96) Id. at 530. (97) Id. at 528. (98) Id. at 592. (99) Id. at 537. (100) Id. at 515. (101) Id. at 537. (102) Id. at 537, 539. (103) Id. at 537. (104) Id. at 511, 522. (105) Id. at 581. (106) Id. at 587. (107) Id. at 590. (108) Id. at 533. (109) Id. at 534. (110) Id. at 594. (111) Id. at 587. (112) Id. at 526. 221 (113) Id. at 588. (114) Id. at 590. (115) Id. at 526, 534. (116) Id. at 552. (117) Id. at 595. (118) Id. at 523. (119) Id. at 524. (120) Id. at 541. (121) Id. at 598. (122) Id. at 540. (123) Id. at 541. (124) Id. at 511. (125) Id. at 569. (126) Id. at 588. (127) Id. at 587. (128) Id. at 588-589. (129) Ibid. (130) Id. at 526. (131) Id. at 589. (132) Ibid. 222 (blank page) 223 THE EXAMINATION OF THE HANDWRITING AND FINGERPRINT EVIDENCE Submitted by Joseph P. MeNalley, examiner of questioned documents, Valley Cottage, N.Y. David J. Purtell, examiner of questioned documents, Chicago, Ill. Charles C. Scott, examiner of questioned documents, Kansas City, Mo. Vincent J. Sealice, president, Forensic Control Systems, Inc., New York, N.Y. ----------------------------- Report to the Select Committee on Assassinations U.S. House of Representatives Ninety-fifth Congress Second Session March 1979 (223) 224 CONTENTS Paragraph Introduction........................................................1 The committee's approach............................................5 Selection of the experts...........................................10 Issues addressed by the experts....................................19 Evidence examined..................................................22 Procedures.........................................................23 Summary of conclusions.............................................27 Findings and conclusions of Joseph P. McNally......................31 Procedures.........................................................31 Conclusions........................................................34 Findings and conclusions of David J. Purtell.......................55 Procedures.........................................................55 Findings...........................................................56 Findings and conclusions of Charles C. Scott.......................80 Procedures.........................................................80 Findings...........................................................87 Concluding remarks................................................144 Findings and conclusions of Vincent J. Scalice....................147 (224) 225 INTRODUCTION* (1) Several critics of the Warren Commission have speculated that there were two Lee Harvey Oswalds. Two versions of this theory have been put forward. One is that the real Lee Harvey Oswald never returned from the Soviet Union; instead, an imposter was sent on a sinister mission. The second is that others, for whatever purposes, used Oswald's name. (2) One of the first proponents of the two-Oswald theory was a philosophy professor named Richard Popkin, who in 1966 published a book entitled "The Second Oswald." (1) Popkin cited the numerous instances recounted iu the Warren Commission report in which people claimed to have seen or dealt, with Oswald under odd or suggestive circumstances. Examples included Oswald being seen at a rifle range, (2) driving a car, (3) and in the company of two Latin-looking men seeking financing for illegal activities from Mrs. Sylvia Odio (a Cuban refugee leader in Dallas). (4) Popkin concluded that the cases of apparent duplication could plausibly be interpreted as evidence that Oswald was involved in a conspiracy, culminating in the events of November 22, 1963. (5) (3) Sylvia, Meagher, in "Accessories After the Fact," also criticized the Commission for not seriously considering the two Oswald possibility,"* * * much less evaluate[ing] the evidence for or against such an explanation." (6) (4) The Warren Commission discounted the incidents, principally on grounds that they had occurred when it was concluded that Oswald was elsewhere--in Mexico at the time of the rifle practice, (7) en route to Mexico at the time of the Odio meeting. (8) It dismissed other incidents because they involved activities in which Oswald apparently did not engage, such as driving. (9) The committee's approach (5) In an effort to resolve the two-Oswald issue, the committee decided to convene a panel of experts to examine samples of handwriting attributed to Oswald. These samples were taken from numerous documents purportedly written and signed by Oswald in the last 7 years of his life. They were organized according to five significant periods: (1) October 1959 through September 1959, when Oswald was in the Marines; (2) October 1959 through June 1962, when Oswald was in the Soviet Union; (3) July 1962 to September 1963. when Oswald lived in Dallas and then in New Orleans; (4) the final week of September 1963, when Oswald visited Mexico: and (5) from the end of September 1963 to the day of the assassination, when Oswald lived in Dallas. The panel was to determine if the handwriting on the documents was that of one person. ------------------------------------- *Materials submitted for this report by the committee's questioned documents panel were compiled by HSCA staff members G. Robert Blakey and Whitney Watriss. (225) 226 (6) The committee also decided to retain another expert to verify, independently, that one or more of Oswald's signatures was in fact his. To make such a determination, the committee sought all fingerprint cards which Oswald had signed. Three were found in the FBI records, two of which were signed: One, dated October 24, 1956, was from Oswald's induction into the Marines; the second, of August 9, 1963, was from his arrest in New Orleans; and the third, unsigned, was dated November 22, 1963, the day of his arrest after the assassination. The expert was to determine if the fingerprints were all Oswald's, which would verify the signatures as Oswald's. (7) The committee reasoned that if these determinations could be made, the two-Oswald theory would be far less plausible. If not, it would be more authoritatively established. (8) This approach of the committee was substantially different from that of the Warren Commission. The Commission had used the documents for evidentiary purposes, for example, to determine if Oswald had used the alias "Hidell" or to link Oswald with the purchase of the Mannlicher-Carcano rifle. It had accepted as fact athat certain of the documents had actually been signed or written by Oswald and compared these with "unknown" documents to establish evidentiary links. (9) The committee, on the other hand, did not assume that any of the documents were written by Oswald. Instead, it sought to prove that one or more signatures were positively Oswald's and that all the documents had been written by the same person. Selection of the experts (10) The committee asked the president of the American Society of Questioned Document Examiners for recommendations on the leading experts in the field of questioned document examination, specifically handwritten documents. The committee then asked each of the people he recommended for their suggestions. THree names appeared consistently. After ascertaining that none had had a prior connection with the FBI or the Kennedy case, the committee requested that they undertake and examination of various documents. The panel members, all of whom belong to the American Society of Questioned Document Examiners, were Joseph P. McNally, David J. Purtell, and Charles C. Scott. (11) McNally received a B.S. and an P.P.A. in police science from the John Jay College of Criminal Justice, University of New York City in 1967 and 1975 respectively. He started in the field of questioned document identification in 1942 with the New York Police laboratory. He has been supervisor of the document identification section of the police laboratory, training officer in the police academy, commanding officer of the police laboratory, and handwriting expert in the district attorney's office of New York County. He retired from the police department with the rank of captain in 1972 and entered private practice. He serves as a consultant to New York's Human Resources Administration. (12) McNally is a fellow of the American Academy of Forensic Sciences, and a member of the International Association for Identification, and the American Society for Testing and Materials. He has lectured at the University of New York City, Rockland College, and the New York Police Academy 227 (13) Purrell received a Ph.D., with a major in mathematics and chemistry, from Northwestern University in 1949. He began his career in questioned document identification in 1942 with the Chicago Police Department, where he served as document examiner in the scientific crime detection laboratory. He retired in 1974 as chief document examiner and captain of police, and entered private practice in 1973. (14) Purtell is a fellow of the American Academy of Forensic Sciences and served as chairman of the questioned document section and chairman of the program committee. He is a past vice president and president of the American Society of Questioned Document Examiners. Puttell has lectured at Northwestern University, the University of Illinois, the University of Indiana and St. Joseph's College, among other schools. He has presented and published numerous scientific papers. (15) Scott received an A.A. degree from Kansas City Junior College in 1930 and a J. D. from the University of Missouri School of Law in 1935, whereupon be became a member of the Missouri bar. While attending law school, he rounded the University of Missouri at Kansas City Law Review and was its first editor-in-chief. He began his career as a questioned document examiner with the Federal Reserve Bank in 1935 and has been in private practice since 1946. The first edition of his three-volume book, "Photographic Evidence," was published in 1942. Now in its second edition, it has become the standard textbook on the subject. (16) Scott served on the first board of directors of the American Board of Forensic Document Examiners. lie has conducted seminars on scientific document examination for more than 20 State bar associations, written numerous professional articles, and, since 1954, has been an adjunct professor of law at the University of Missouri School of Law. (17) The expert selected for the print--finger and palm--analysis was Vincent J. Sealice, president of Forensic Control Systems, Inc., of New York City. (18) Sealice, before entering private practice, served with the New York City Police Department from 1956 to 1977, where he attained the rank of detective first grade. He has been a lecturer and instructor on crime scene examination and latent print identification at the New York City Police Academy, a lecturer on fingerprint identification and courtroom technique at Brooklyn Law School, and he formulated and taught a course on crime scene examination for the detective division of the New York City Police Department. Issues addressed by the experts (19) The committee asked McNally, Purtell, and Scott to address four issues: 1. Were the signatures "Lee Harvey Oswald" and "Lee H. Oswald" on the various documents written by the same person? 2. Was the script writing on the various documents. which was purported to be Oswald's, done by the same person? 3. Was the Russian writing on the various documents, which was purported to be Oswald's. done by the same person? 4. Was the "historical diary" written in one sitting? 228 (20) Subsequently, the committee asked Puttell and McNally to look at whether the signature "A. J. Hidell" on the June 15, 1963, Fair Play for Cuba card was written by Marina Oswald. In addition, McNally was asked to determine whether the signature "Jack Ruby" on the undated Cuban identification card had been written by Jack Ruby. (21) Scalice was asked to verify that the finger and palm prints which appeared on the three cards were of the same person. Subsequently, he was asked to examine some other documents. Evidence examined (22) Handwriting.-- The committee gathered some 50 documents to be examined.* Following is a list and description of those items. 1. October 24, 1956. Original of U.S. Marine Corps enlistment contract and record, service No. 1653230, signed Lee Harvey Oswald. Blue ink; nib pen. Location: Department of Defense (hereinafter DOD). (JFK exhibit F-479.) ** 2. October 24, 1956. Carbon of item 1, with an original signature, Lee Harvey Oswald. Blue ink; nib pen. Location: DOD (JFK exhibit F-479a.) 3. October 24, 1956. Loyalty certificate for personnel of the Armed Forces, signed Lee Harvey Oswald. Blue ink; nib pen. Location: DOD. (JFK exhibit F-481.) 4. October 24, 1956. U.S. Marine Corps examination of applicant by recruiting officer, signed Lee Harvey Oswald. Blue ink; nib pen. Location: DOD. (JFK exhibit F480.) 5. October 24, 1956. ILS. Marine Corps record emergency data, signed by Lee Harvey Oswald. Blue ink; nib pen. Location: DOD. (JFK exhibit F478.) 6. October 24, 1956. Armed Forces fingerprint identification card, numbered 327 925 D, signed Lee Harvey Oswald. Blue ink; ballpoint pen. Location: Federal Bureau of Investigation (hereinafter FBI). (JFK exhibit F482.) 7. October 25. 1956. U.S. Marine Corps miscellaneous information and index form (NAVMC H8 (1)-PD), signed Lee H. Oswald. Blue-black ink; nib pen. This document bears a second signature, reading Lee H. Oswald, dated October 28, 1956. blue-black ink, nib pen; and a third signature, reading Lee H. Oswald, dated May 2, 1957, black ink, nib pen. Location:DOD. (JFK exhibit F-483.) 8. May 8, 1958. Identification card, U.S. Forces, Japan, signed Lee H. Oswald. Location:National Archives (hereinafter Archives). Found in Oswald's wallet on the day of his arrest. (FBI exhibit D-225: B 1-9; JFK exhibit F-505.) 9. September 10, 1959. U.S. passport No. 1733242 signed Lee H. Oswald. Faded blue ink; ballpoint pen. Location: Archives. (Warren Commission exhibit 946, hereinafter CE 946: JFK exhibit F-486.) ------------------------------------ *The items listed here number 63; the difference in numbers is due to examination of more than one copy of an item, that is, an original and a photo reproduction. **Copies of most of the documents appear at the end of this report. Numbers 53 and 61 were not available, but are contained in committee files at the Archives. 229 10. September 10, 1959. Photograph of passport bearer of U.S. passport No. 1733242, appearing on page 4, signed Lee H. Oswald, and photograph of "Baby Lee Oswald," on page 14, signed ,lune Lee Oswald, father. Black ink; ballpoint pen. Location: Archives. (CE 946;JFK exhibit F-486.) 11. September 11, 1959. U.S. Marine Corps notice of obligated service, signed Lee Harvey Oswald. Blue ink; ballpoint pen. Location:Archives. (JFK exhibit F-485.) 12. September 11, 1959. U.S. Marine Corps security termination statement and index, signed Lee Harvey Oswald. Blue ink; ballpoint pen. Location: DOD. (JFK exhibit F484.) 13. September 11, 1959. Carbon copy of Armed Forces of the U.S. report of transfer or discharge, signed Lee Harvey Oswald, with a carbon copy signature. Location:DOD. (FBI exhibit D-18.) 14. September 14, 1959. Selective Service System registration card, signed Lee H. Oswald. Black ink; ballpoint pen. Location: Archives. (JFK exhibit F487. ) 15. September 14, 1959. Selective Service System registration certificate, signed Lee H. Oswald. Black ink; ballpoint pen. Location:Archives. (JFK exhibit F-505.) 16. October 16, 1959 to March 27 1962. Historical diary, 12 handwritten pages. (Only p. 11, dated ,Inly 15, 1961 to January 4, 1962, was examined, as all other pages were badly stained with fingerprint developer and are entirely unsuitable for handwriting examination.) Location: Archives. (CE 24; JFK exhibit F-491.) 17. November 3, 1959. Declaration requesting revocation of U.S. citizenship, signed Lee Harvey Oswald. Purple ink; nib pen. Location: Archives. (CE 244; JFK exhibit F-488.) 18. November 15, 1959. Photocopy of handwritten account of interview with Miss Aline Mosby, UPI reporter. Unsigned. (The original of this document was also submitted but could not. be examined because it was completely covered and stained with fingerprint developer.) Location: Archives. (CE 2717: JFK exhibit F-489. ) 19. 1960, undated. Political discussion, handwritten on stationery the Holland-American Line; 15 pages. Blue ink; nib pen. Location: Archives. (FBI exhibits 123 and 124; CE 25; JFK exhibit F-490.) 20. 1962, undated. Self-questionnaire. Location: Archives. (FBI exhibit 16; CE 100 and part of 24.) 21. 1962, undated. Photocopy of document identified as a so, if questionnaire. Original was stained and unsuit:able for examination. Location: Archives. (JFK exhibit F-402.) 22. January 17, 1962. Affidavit of support, addressed to the American Embassy, Moscow, U.S.S.R, signed Lee H. Oswald. Blue ink; nib pen. Location: Archives. (CE 775; JFK exhibit. F492.) 23. February 20 (1962). Russian script on lined paper, from "Alek" to "Marina" and "June." Location: Archives. (FBI exhibit 134; CE 59; JFK exhibit F-493.) 24. March 24, 1962. Entry papers of Marina Oswald, including a fingerprint identification card. (FBI exhibit D-10.) 230 25. June 10, 1969. Two-page handwritten letter to the "Worker," 23 West 26th Street, signed Lee H. Oswald. Blue ink; ballpoint pen. Date was appended with a different pen. Location:Archives. (Document marked "A. Johnson exhibit No. 1"; JFK exhibit F-494.) 26. July 13, 1962. Letter to Leslie Welding Co. signed Lee H. Oswald; written on part of a page from a yellow legal pad. Blue ink; ballpoint pen. Location: Archives. 27. October 9, 1969. Application for P.O. Box No. 2915, signed Lee H. Oswald. Black ink; ballpoint pen. Location: Archives. (CE 791; JFK exhibit F-496.) 28. March 8, 1963. Photocopies of a note in Russian to Ruth Paine from Marina Oswald. Location:Archives. (CE 404.) 29. March 12, 1963. U.S. postal money order No. bearing handwritten fill-ins as follows: Klein's Sporting Goods, A. Hidell, P.O. Box 2915. Dallas, Tex. Blue ink, ballpoint pen. Location: Archives. (CE 788; JFK exhibit F-509A and 509B.) 30. March 12, 1963. Enlargement of microfilm reproduction of Klein's order form for rifle from A. Hidell, superimposed on envelop, postmarked March 12, 1963, addressed to Klein's, Dept. 358, 227 W. Washington Street, Chicago 6, Ill., with return address: A. Hidell. P.O. Box 2915, Dallas, Tex. Location:Archives. (CE 773: Cadigan's exhibit 1; JFK exhibit F-504.) 31. May 4, 1963. Photograph of man with rifle and newspapers. On the back of the, photograph is a handwritten notation reading "To my friend George from Lee Oswald 5/IV/63" and, in Russian, the statement "Copyright G de M." Also in Russian is writing which translated as "'Killer of Fascists--Ha-Ha-Ha!!" Blue ink; balipoint pen. Location: House Select Committee on Assassinations (hereinafter HSCA), which obtained it from the effects of George de Mohrenschildt after his death in 1977. (JFK exhibit F-183 and 184, F-382 and 383.) 32. May 26 (1963) * Two-page letter to Fair Play for Cuba Committee, signed Lee H. Oswald. Blue ink; ballpoint pen. Location: Archives. (Document also marked "V. T. Lee No. 2;, JFK exhibit F-497.) 33. June 15, 1963. Fair Play for Cuba Committee, New Orleans chapter, signed Lee H. Oswald, with A.J. Hidell signing as chapter president. Found in Oswald's wallet on the day of his arrest. Location: Archives. (JFK exhibit F-505.) 34. June 24, 1963. Passport application, signed Lee H. Oswald. Blue ink; ballpoint pen. Location: FBI. (CE 781; JFK exhibit F-40.) 35. June 24, 1963. Passport photograph attached to item 34, signed Lee H. Oswald. Blue ink: ballpoint pen. Location: Archives. 36. August 9, 1963. Fingerprint identification card of New Orleans Police Department, signed Lee H. Oswald. Blue ink; ballpoint pen. Location: Archives. FBI current arrest or receipt, dated 1963. Location: Archives. (JFK F400.) 37. August 9, 1963. Photocopy of fingerprint card and attached mug shots, New Orleans Police Department, signed Lee H. Oswald. Location: FBI. ------------------------ *Year was derived from content. 231 38. August 28, 1963. Handwritten letter to Central Committee C.P. (Communist Party), USA, signed Lee H. Oswald. Blue ink; ballpoint pen. Location: Archives. (Document also marked "A. Johnson exhibit No. 4"; JFK F-498.) 39. September 27, 1963. Photocopy of a page from a hotel register, signed, on line 18, "Lee, Harvey Oswald, U.S.A. (Texas) PHOTO. U.S. citizen." Location:Archives. (FBI exhibit D-36; JFK F-499.) 40. September 27 1963. Photographs (one of the entire document and one of the signature) of the original of the visa application, Cuban Consulate, Mexico City, signed Lee H. Oswald. Location: Archives. (CE 2564; JFK F-407 entire document.) 41. September 27, 1963. Photograph of the carbon copy of item 40, shown to the committee staff when they met with President Fidel Castro in Havana, Cuba, with an original signature, Lee H. Oswald. Location: HSCA. (JFK F-408.) 42. October (no date), 1963. Letter to the Russian Embassy. (JFK F-500.) 43. October 15, 1963. Employment application, with face sheet signed Lee H. Oswald. Blue ink; ballpoint pen. Location: Archives. (FBI exhibit D-18; JFK F-503.) 44. October 16, 1963. Employee's W-4 withholding exemption certificate, signed Lee H. Oswald. Blue ink; ballpoint pen. Location: Archives. (FBI exhibit D-90; JFK F-501.) 45. November 1, 1963. Application for P.O. Box 6225, two cards, each signed Lee H. Oswald. Blue ink; ballpoint pen. Location: Archives. (CE 792; JFK F-495.) 46. November 1, 1963. Receipt for key to P.O. Box 6225, signed Lee H. Oswald. Blue ink; ballpoint pen. Location: Archives. (CE 792; JFK F-495.) 47. November 8, 1963. Two photographs of a facsimile copy of a handwritten letter to Mr. Hunt. One is of the entire document, the other an enlargement of the signature. These were obtained by the committee from a researcher in Dallas, Tex. Location: HSCA files. (JFK F-506.) 48. November 9, 1963. Photomechanical (halftone) reproduction of a typewritten letter to the Consular Division, Embassy, U.S.S.R. Washington, D.C., signed Lee H. Oswald. Location: Archives. (Photomechanical reproduction--CE 15; JFK F-500.) 49. July 18, 1964: Exemplar (standard) signatures and writing of Jack Ruby. Location: Archives. 50. Undated. Photograph of unsigned rough draft of item 48. Location: Archives. (JFK F~500.) 51. Undated. Handwritten speech, nine pages. Green ink: nib pen. Location: Archives. (FBI exhibit 117:CE 97: JFK F-508.) 52. Undated. Two receipts for salary from the Texas School Book Depository, signed Lee H. Oswald. (FBI exhibit 422. ) 53. Undated (August?). Photograph of Cuban identification card, flight 751, signed Jack Ruby. (JFK F-583.) Location: HSCA files. 54. Undated. Exemplar writing of Marina Oswald. including seven slips of paper containing the writing "A. J. Hidell." Location: Archives, HSCA. 232 55. Undated. Dallas Public Library card, expiring December 7, 1965, signed Lee H. Oswald. Location:Archives. (JFK F-505, B1-10.), 56. Undated. Note in Russian, consisting of 10 lines of handwriting, signed, in Russian, "Alek." Location: Archives. (FBI exhibit JFK F-507.) 57. Undated. Note in Russian consisting of two pages of 11 handwritten instructions concerning the Walker incident, referred to as "the Walker Note." Location: Archives. (FBI exhibit 30;CE 1;JFK F-510.) 58. Undated. Certificate of service, U.S. Marine Corps, signed Lee Harvey Oswald. Location: Archives. (FBI exhibit. D-225.) 59. Undated. Social security card, 433-54-3937, Lee Harvey Oswald; unsigned. Location: Archives. (FBI exhibit D-225.) 60. Undated. Complimentary card, GA-Joen Kanko Hotel. Location: Archives. 61. Three photographs of Oswald, one with the notation on the back, "taken at Camp Pendleton Feb. 5." Location: Archives. 62. Undated. Slip of paper with the following handwriting: "The Worke 23 W. 26th St. New York 10, N.Y. The Worker Box 28 Madison Sq. Station, New York 10, N.Y. Embassy USSR. 1609 Decatur St. N.W. Washington, D.C." Location: Archives. 63. November 22, 1963. Photograph of fingerprint form of the Dallas Police Department. Location: FBI. (CE 627, 630.) Procedures (23) The panel members traveled to Washington, D.C. at various times to examine and photograph originals of documents to be examined. These were located at four places:The National Archives, the Department of Defense the FBI, and the offices of the committee. The panel members prepared photographs of the originals for further study in their own laboratories. (24) The panel met as a whole on July 6, 1977, to review the original documents and discuss their respective findings. Each member then prepared a final report of his findings and conclusions (these also provide further detail on the procedures followed by each member). (25) The panel followed standard procedures and techniques in its examinations. The writings and signatures were looked at individually and in juxtaposition with each other, taking into consideration the gross characteristics of the writing process, writing skill, slant, speed, proportions of the letters, ratio of small to capital letters, height ratio, lateral spacing, and overall writing pattern. Significant differences were looked for. A stereoscopic microscope was used for minute examination and comparison of individual letters and characteristics. (26) Scalice examined and compared the inked impressions on the three fingerprint cards on June 8, 1978, at the latent print section of the Federal Bureau of Investigation in Washington, D.C. 233 SUMMARY OF CONCLUSIONS (27) With the restrictions and reservations stated in each panel member's final report,* the members conclude, generally, that the signatures and handwriting purported to be by Oswald are consistently that of one person. Because of the poor condition of the historical diary, they are unable to conclude firmly whether it was written at one or more than one sitting. On balance, it appears to have been written at one or a few sittings. (28) Purtell and McNally conclude the name "A. J. Hidell" was written on the 1963 Fair Play for Cuba card by the same person who wrote the exemplars attributed to Marina Oswald. (29) Finally, McNally concludes that the name "Jack Ruby" written on an undated Cuban identification card was by the same person who wrote the exemplars attributed to Jack Ruby. (30) Scalice concluded that all inked finger and palm prints were identical and were Lee Harvey Oswald's. FINDINGS AND CONCLUSIONS OF JOSEPH P. MC NALLY Procedures (31) I conducted an examination and comparison of the signatures and writings on the items described in this report. At the time of the initial work in Washington, D.C., I made color photomacrographs of the signatures and the writings on these documents. I then made slides from the photomacrographs, which I subsequently projected and studied. The signatures were a particular focus of my examination. (32) I first met with committee staff in Washington, D.C., on September L 1977, to examine and photograph signatures and writings on documents available at the Department of Defense and the National Archives. On September 17 1977, I went to the committee's offices to examine and photograph a photoreproduction designated item No. 47. On May 8, 1978, I returned to Washington, D.C., to make additional examinations and photographs. These were made at the Department of Defense, the National Archives, and the committee offices. (33) On July 6, 1978, I met with other members of the handwriting panel to review the documents examined and to consult with them. Subsequently, I prepared my final report with my findings and conclusions. Conclusions (34) I, The signatures "Lee Harvey Oswald" and "Lee H. Oswald" on the following documents were all written by the same person: 1,2,4,5,7,11, and 12. Marine Corps documents. 3. U.S. Armed Forces Loyalty Certificate. 6. USMC fingerprint form. 8. ID card---U.S. Armed Forces, Japan. 9 and 10. Three (3) passport signatures. 13. Carbon of U.S. Armed Forces Report of Discharge. ---------------------------------- *In particular, members noted that not all documents were available in their original. It is standard practice in the profession of questioned document examination to make definitive conclusions only about documents examined in their original. Thus the panel members gave only tentative opinions for items provided them in some type of facsimile. 234 14. Selective Service registration. 15. Selective Service card. 17. Citizenship revocation. 22. Support affidavit. 25. Letter to "The Worker". 27, 45 and 46. Signatures on U.S.P.O. applications (4). 31. Photo of Lee Oswald (back). 32. Letter to "Fair Play for Cuba". 33. Fair Play for Cuba card. 34. Passport application. 36. New Orleans Police Department fingerprint form, dated Aug. 9, 1968. 37. Photocopy of New Orleans Police Department fingerprint form. 38. Letter to the "Communist Party U.S.A." 39. Hotel registry. 40. Application for Cuban visa. 41. Photograph of carbon of application for Cuban visa. 42. Letter to Russian Embassy. 43. Employment form. 44. Form W4. 45. P.O. Box 6225 application. 46. Receipt for key to P.O. Box 6225. 48. Photomechanical copy of letter to Russian Embassy. 55. Dallas Public Library card. (35) II. The script writing on the following documents was done by the same person: 17. Citizenship revocation. 19. Stationery of Holland-American Line. 20. Self-questionnaire. 21. Photocopy of self-questionnaire. 22. Support affidavit. 25. Letter to "The Worker". 29. Xerox of Klein's money order. 30. Letter to "Fair Play for Cuba". 38. Letter to "Communist Party U.S.A.". 42. Letter to the Russian Embassy. 48. Photomechanical copy of letter to Russian Embassy. (36) III. A number of documents have script and handprint, both of which are by the same person (the script writings of these documents correspond to that of documents listed above under I and II): 16. Historical diary. 18. Aline Mosby interview. 26. Employment application with letter. 30. Envelope and order form--Klein's. 43. Employment application and letter of resignation. (37) IV. A few documents have handprint only. On those listed below, all the handprint is by the same person, and it corresponds to the handprint on documents listed above under III. Since the script in items under III corresponds to the script in items under II, it can be concluded that the items under II, III, and IV correspond. 9. Inside cover of passport. 27, 45 and 46. U.S.P.O. forms--box rental. 51. Speech. 235 (38) V. In summary, the script writing (much of it on documents also bearing the signature of Lee H. Oswald) is identifiable with the signatures, "Lee H. Oswald." From the script writing on the documents described in section II, it is possible to create composite signatures, "Lee Harvey Oswald" and "Lee H. Oswald," which correspond to the Oswald signatures on the documents listed in section I. (39) VI. The Russian language writing on documents 23, 56, and 57 is by the same person. Although there are a few letter design forms which appear to be in the Cyrillic alphabet, the bulk axe in the Latin alphabet and correspond to their counterparts in the script and handprint in the documents listed in sections I, II, III, and IV above. (40) VII. The two signatures, "Lee H. Oswald," in item 52 (receipts salary--Texas School Book Depository) do not correspond to the Oswald signatures as described under section I. The handwriting appears to be more skillful, with a more rhythmic flow. It varies in slant and differs in proportion. The overall writing pattern differs from the Oswald signatures in section I, as do the individual letter designs. The "L" of item 52 is taller and without an eyelet loop at the top right of the "L" as found in the section I signatures. The "H" of item 52 is distinctly different from the "II" in the section I signatures. The "0" of item 5'2 retraces on itself, not the case in the section I signatures, where it loops around at the top right and usually swings into the following "s". The "d" of item 52 reverses slant to go backhand, which does not occur in the section I signatures. (41) VIII. The signature, "Lee Harvey Oswald," on the Hunt note (item 4-7) does not correspond to the Oswald signatures described under section I. To begin with, the bulk of the documents which are signed with the full name, "Lee Harvey Oswald," are more formal in tone. For example, the full name appears on all but one of the Marine Corps documents. The full name appears infrequently elsewhere-usually only the first name, middle initial, and last name are used. Further, in the Hunt note, the middle name "Harvey" is misspelled-the "e" appears to be missing; the "H" of "Harvey" differs from that found in the section I signatures; the "ar" of "Harvey" is ellided to a point that does not occur in any section I signatures; the "0" of "Oswald" is retraced part of the way along the left side, not true of the section I Oswald signatures; and the ending "d" of Oswald is smaller than the preceding "l", whereas most of the ending "d"s of the section I signatures are taller than the "l" (only in signatures that appear to be "squeezed-in" is the end "d" shorter than the preceding "1"). (42) While the script writing on the Hunt note is similar in pictorial quality to the writings under section II, the format of the note differs from that of the notes and letters of section II. The writing line is so exact as almost to give the impression it has been made on a ruled line. Usually Oswald writes in an arhythmic manner--for example, with an irregular and crooked writing line. This writing creates the jumbled effect apparent in the section II documents. (43) From the examinations of item 4-7, it was determined that the signature does not correspond with any of the Oswald signatures of section I. Similarly, the writing does not correspond to that in the section II Oswald documents. (44) I would like to note, however, that the quality of the original photoreproductions of the Hunt note was poor. Under the best of cir- 236 cumstances, reproductions lack clarity and detail. Here, as can be seen from the copies, the original photoreproduction was out of focus, giving the document a fuzzy appearance. Accurate analysis was difficult. The note is highly suspicious. The original would have to be checked in order to make a more definite analysis and reach a definitive conclusion. (45) IX. An examination and comparison was made of writings and signatures on documents attributed to Marina Oswald. The writings on the note (item 28) are such poor copies that it is virtually impossible to make a definite determination as to whether they correspond with the signatures of Marina Oswald on item 24. There is some similarity between the name in the return address on the envelope of item 28 and the signature of Marina Oswald on her entry papers (item 24), but the return address name is obscured to some extent by the postmark. The rest of the writing on the note (item 28) is not sufficiently parallel to the writing on her entry documents (item 29) and exemplars (item 54) to warrant any effective determination. (46) The name, "A. J. Hidell" on the Fair Play for Cuba card (item 33) was examined and compared with the exemplar writings of Marina Oswald (item 54). It was determined that. the "A. 5. Hidell" of the card (item 33) was written by Marina Oswald (as in item 54). The writing pattern of the signature on the card corresponds with that of the name "A. J. Hidell" as written by Marina Oswald on item 54. The Hidell signature in question is written with the same degree of writing skill as evinced by Marina Oswald. The slant, speed, proportions, et cetera, of the Hidell signature is matched in the writings of Marina Oswald. The design, form, and execution of stroke making up the individual letters of the Hidell signature in question (item 33) correspond to those of the letters in the writing of Marina Oswald (item 54). (47) X. The "Jack Ruby" signature on the Cuban identification card (item 53) was examined and compared with exemplars of Jack Ruby (item 49). It was determined that the "Jack Ruby" of the Cuban identification card was written by the author of the exemplar signatures attributed to Jack Ruby (item 49). While there is an odd "J" in the identification card which does not occur in the Ruby exemplars, the rest of the letters tally in all respects. The signature has been written quickly, easily, and fluently, consistent with the writing pattern of the known exemplars. The odd "J" may be "accidental" or could be accounted for in additional writing of Ruby, most likely in spontaneous writing contemporaneous with the signature of the identification card. "Request" writing, such as that of item 49, sometimes differs slight extent from "spontaneous" writing. (48) XI. A check was made of the historical diary (item 16). The 12 pages were written with the same type of writing instrument. The paper used for 11 of the 12 pages is similar; only the last page differs--it is appreciably thinner. The writing bas a continuity from page to page and line to line that is indicative of being written about, or at, the same time. It does not give the impression of being "random" as would be expected of a diary extended over a period of time. It appears that this diary has been written within a short period of time and not over any extensive period. 237 Summary of conclusions (49) Virtually all the Lee H. Oswald and Lee Harvey Oswald signatures arc by the same person. There is some normal variation among the signatures, and no significant differences along the Oswald sig natures identified as being the same. The overall writing pattern consistently similar, and the individual letter designs match throughout without major differences. The same holds true for the script and handprint on these documents that are identified as being written by the same person. (50) The same writing is on the U.S. Postal money order to Klein's (item 29) as is on the various letters and correspondence. The same writing is on the order form and envelope (item 30) as is on the letters and on the inside cover of the passport (item 9). (51) The writing and signatures that appear on the letters (items 25, 32, 38, and 42) agree with the writing and signatures on the U.S. Post Office applications for post office boxes (items 27, 45, and 46). (52) The signature and writing on the back of the photograph (item 31) agree with the signatures and script writing of Oswald (sections and II). (53) Differences indicative of different authorship were found on the "Hunt" note (item 47) and the salary receipts (item 52). (54) It appears that the historical dairy (item 16) was written with- in a short period of time. FINDINGS AND CONCLUSIONS OF DAVID J. PURTELL Procedures (55)Items 1,2,4,5,6,7,8,9,11,12,15,16,17,18,19,20,22,23,24,25, 27,29,31,32,33,34,36,38,39,40,43,45,47,48,51,54,55,56,57,58,59,61,and 62 were studied, both visually and microscopically. A detailed drawing was made of all features observed in tile writings. Later, each piece of writing was compared with every other piece of evidence. Photographs were taken of the evidence, and these were studied along with the detailed drawings. Thus the evidence was evaluated a total of three times. Findings (56) The examinations and comparisons revealed that all the writ- ings were executed by a person having limited writing skill. The writings show physical evidence of natural movement and manner, with some normal variations. The carefree qualities and the unrestrained movements associated with genuine writing are present. None exhibit the characteristics of simulation produced by imitators attempting to duplicate the writing of another. The writings have similarities in the formation of letters, quality of writing, movement within tile writing, size and proportions of letters and parts of letters, beginning and ending strokes. pen pressure, slope of the writing, spacing, alinement, direction, and speed. (57) These similarities and the lack of any unexplainable differences resulted in the following findings and opinions: (58) A. One person wrote the signatures, Lee Harvey Oswald, Lee H. Oswald, and Lee Oswald on documents 1, 4, 5, 6, 7, 8, 9, 11, 12, 15, 17, 22, 25, 27, 31, 32, 33, 34, 36, 38, 43, 45, and 55. 238 238 (59) B. The person who wrote the signatures on the above-list doc- uments also completed the messages on documents 17, 22, 25, 31, 32, 38, and 43. (60) C. The person who wrote the signatures and completed the messages on the documents listed in A and B above executed the handwriting on documents 18, 19, 20, 48, 61, and (61) D. One person executed the handprinting appearing on docu- ments 9, 27, 34, and 45, all of which were signed Lee H. Oswald. (62) E. The person who hand printed the information on the docu- ments listed in D above, also hand printed the material on document 51.* (63) F. With regard to the Russian writing on items 23, 56, and 57, this examiner is not familiar with this language and the characteristics of the various writing systems used. (64) It is almost impossible to distinguish between class characteristics and individual characteristics unless the writing styles of a language are known. (65) This examiner is, therefore, unable to render definite opinion, but can point out that there are similarities between the writing in in items 23, 56, and 57 and the handwriting on the items listed in A, B, and C above. (66) G. With respect to the timespan of the historical diary (item 16), an answer cannot be provided because of the present condition of the paper. The documents had been processed by the silver nitrate method in an attempt to develop latent fingerprints. While, a recognized method, the drawback is that it soils the paper; the silver nitrate which remains on the paper causes it to turn black in time. Today, the pages are in very poor condition, and though the message can be read in part, it is a very difficult task. One observation that can be reported is that one sheet of paper is of a different weight (thickness) than the other sheets. (67) H. The committee requested that a determination be made as to whether the person who prepared items 24 and 54 also wrote the name, "A. 5. Hidel on the Fair Play for Cuba Committee card, dated June 15, 1963 (item 33). Known (68) Known handwriting of Marina Oswald appears in: Item 24--one fingerprint identification card, dated March 24, 1962; and Item 51--seven slips of paper containing the writing of the name, "A. J. Hidell" ,and "A. J. Hidell." (69) The items above were examined to determine their individual writing features, as was the signature on the FPCC card (item 33). The two groups of writings were then compared. (70) The examiner is of the opinion that the person who executed the handwriting on item 54 wrote the name, "A. J. Hidell" on the Fair Play for Cuba Committee card (item 33). This opinion is based on similarities in letter formation, quality of the writings, size, and proportions of the letters, beginning and ending strokes, pen pressure, and slant of the writing. No unexplainable differences could be noticed. ---------------------------------------- *Attached to and made part of this report are photographic illustrations (Purtell Exhibits 1 and 2) made up of signatures demonstrating all the points of similarities noted above. 239 Limitations on the examination (71) Five items of evidence were not examined in the original, but were copies. Photocopies have several limitations. They do not reproduce all the fine details in handwriting needed in making an examination and comparison. At best, they do not produce as sharp an image as a properly produced photograph, and they lack tonal gradations, a result of the contrasting process of reproduction. In addition, it is possible to incorporate or insert changes and alterations into copies. A method frequently used is to paste together parts of documents to make one fradulent document, which is then copied. If the first copy can pass inspection, it will be used; if not, it will be reworked to eliminate all signs of alteration. This amended copy is then recopied for the finished product. This is usually referred to as the "cut and paste" method. (72) Document examiners only render a qualified or conditional opinion when working from copies. They stipulate that they have to examine the original before a definite opinion will be made. (73) Because of problems with the following documents, no definite opinion can be rendered: (74) Item 18, a halftone copy of a photograph of the original document. This is at least a third generation copy and is not suitable for comparison. (A halftone copy consists of very small dots and not continuous lines.) (75) Item 29 was a Xerox copy made from a microfilm copy. Such a second generation copy has the defects of both processes. (76) Item 39 was a photograph taken without a scale so that the magnification or reduction of the writing could not be determined. (77) Items 40 and 41 were very poor quality photographs and lacked scales to determine the size of enlargements. (78) Item 47 was a photograph of an out-of-focus facsimile copy. stead of having clear discernible lines, the copy has indistinct and blurred outlines. Such a muddy and unclear copy gives the appearance that it might have been so made for a purpose. (79) It should be noted that pictorial similarities can still be noticed between the handwriting appearing on items 18, 29, 39, 40, and 41 listed above, and the documents that have been identified as being written by one person (see A, B, and C). While the handwriting appearing in item 47 contains some of the pictorial similarities, the quality of the writing appears different, and the signature has a strange and distorted appearance. 240 PURTELL ATTACHMENT NO. 1 241 PURTELL ATTACHMENT NO. 2A 242 PURTELL ATTACHMENT NO. 2B 243 FINDINGS AND CONCLUSIONS OF CHARLES C. SCOTT Procedures (80) 1. I examined all documents except items 8, 23, 24, 28, 52, 56, 57, 60, 61, 62, and 63. (81) 2. Minute scrutiny of the signatures and other handwriting purporting to be that of Oswald was conducted under stereoscopic microscope with reflected light, sidelight from all angles, transmitted light, and ultraviolet rays. In addition, they were studied under infrared rays by means of an infrared image converter. (The primary purpose of the first two methods is to detect any evidence of tracings, alterations, erasures, or obliterated writing. ) (82) 3. Microscopic examination was also used to determine the color of ink and type of pen used in the execution of each document. (83) 4. Photographs of original documents were studied in the laboratory in Kansas City. (84) 5. Photographic comparison charts of the purported signatures of Oswald were prepared and evaluated for most of the documents. (85) The above-described methods of examination were applied to all original documents submitted for examination, with the exception of two fingerprint cards. dated October 24. 1956, and August 9, 1963 (items 6 and 36), which were not received in time for this type of treatment. (86) Photographic reproductions could only be compared visually with other photographic reproductions or with original documents. All conclusions based solely upon photographic reproductions are necessarily tentative and inconclusive. since they cannot reveal much about pen pressure and other dynamic qualities of handwriting. Further, they sometimes conceal, rather than reveal, evidence of tracings, alterations, erasures, or obliterated writing. Findings (87) Question. Are all of the signatures and other writings on the documents purported to have been written by Oswald by one and the same person? (88) Opinion. After very careful examination and comparison of the documents provided, I am of the opinion that, on the following original documents, Oswald's purported signatures and other writings are all in the same handwriting and were all written by one and the same person. (89) Item l--October 24, 1956. U.S. Marine Corps enlistment con- tract and record, signed "Lee Harvey Oswald." (90) Item 2--October 24, 1956. Carbon copy of item 1 bearing an original signature, reading "Lee Harvey Oswald." (91) Item 3--October 24, 1956. Loyalty certificate for personnel in the Armed Forces, signed "Lee Harvey Oswald." (92) Item 4--October 24, 1956. U.S. Marine Corps examination of applicant by recruiting officer, signed "Lee Harvey Oswald." (93) Item 5--October 24, 1956. U.S. Marine Corps record of emergency data, signed "Lee Harvey Oswald." (94) Item 6--October 24, 1956. Armed Forces fingerprint card, signed "Lee Harvey Oswald." 244 (95) Item 7--October 25, 1956. U.S. Marine Corps miscellaneous information and index form, signed "Lee H. Oswald" in three places. (96) Item 9--c.* September 10, 1959. U.S. passport, signed "Lee H. Oswald." (97) Item 10--c.* September 10, 1959. Photograph on page 4 of U.S. passport, signed "Lee H. Oswald." (99) Item 11--September 11, 1959. U.S. Marine Corps notice of obligated service, signed "Lee Harvey Oswald." (100) Item 10--September 11, 1959. U.S. Marine Corps security termination statement, signed "Lee Harvey Oswald." (101) Item 15--September 14, 1959. Selective Service System registration card, signed "Lee H. Oswald." (102) Item 16--July 15, 1961 to January 4, 196e. Page 11 of a 10-page diary. (103) Item 17--November 3, 1959. Declaration requesting revocation of U.S. citizenship, signed "Lee Harvey Oswald." (104) Item 19--1960, undated. Handwriting on Holland-American Line stationery. (105) Item 22--January 17, 1960. Affidavit of support addressed to the American Embassy, Moscow. signed "Lee H. Oswald." (106) Item 25--June 10, 1962. Letter to the "Worker," 23 West 26th Street, signed "Lee H. Oswald." (107) Item 26--c. July 13, 1962. Letter to Leslie Welding Co., signed "Lee H. Oswald." (108) Item 27--October 9, 1962. Application for P.O. Box No. 2915, signed "Lee H. Oswald." (109) Item 31--May 4, 1963. Photograph of man with rifle. On the back of this photograph is a notation reading "To my friend George from Lee Oswald 5/IV/63." (110) Item 32--May 26, (1963?). Letter to Fair Play for Cuba Committee, signed "Lee H. Oswald." (111) Item 34--June 25, 1963. Passport application, signed "Lee H.. Oswald." (112) Item 35--June 25, 1963. Passport photograph attached to application and signed "Lee II. Oswald." (113) Item 36--August 9, 1963. Fingerprint card of New Orleans Police Department, signed "Lee H. Oswald?" (114) Item 38 August 28, 1963. Letter to central committee of the Communist Party, signed "Lee H. Oswald." (115) Item 43--October 15, 1963. Employment application, signed "Lee H. Oswald." (116) Item 44--October 16, 1963. Employee's withholding exemption certificate, signed "Lee II. Oswald." (117) Item 45--November 1, 1963. Two cards. Application for P.O. Box 6225, both signed "Lee H. Oswald." (118) Item 46--November 1, 1963. Receipt for key to P.O. Box 6225, signed "Lee II. Oswald." (119) Item 51--Undated. Handwritten speech. (120) I examined each of the above-described documents (with the exception of items 6 and 36) under a stereoscopic microscope by reflectred light, side light from all angles, transmitted light, and ultra- --------------------------------------- *Circa is used because a passport is usually signed by the holder after receipt, which is often different than that of the date of issuance. 245 violet rays. I also inspected them under infrared, using an infrared image converter. (121) I did not find any evidence of tracing or copying in any of the signatures or other handwriting purporting to be Oswald's on any of the original documents, nor did I lind any material erasures, alterations or obliterations. All seem to have been executed in the ordinary course of business without any suspicious signs. Equally important, all the purported signatures and writings of Oswald on the above described documents conform with each other in letter formation, slant, proportions, alignment, and connecting strokes--allowing for normal variation. If Oswald's writing were imitated by some other person, in all probability the imitations would display a slavish uniformity somewhat like that of rubber stamping. There was no such suspicious uniformity and lack of natural variation in the signatures and writings. (122) Also highly significant was that all the signatures and handwriting on the above-described original documents were executed with the same type of free rapid writing movement and without any indications of suspicious hesitations or skips. (123) Where, as here, two or more writings conforming with each other in the pictorial aspects of form or design (allowing for natural variation) show evidence of having. been written with the same type of writing movement and rhythm, and lack any indications of tracing or other imitiative processes, the conclusion is inescapable that all were written by the same person. (124) With respect to the carbon copies and photographic reproductions submitted for examination, the form or design, slant, proportions, connecting strokes, and the like conformed with the writing on original documents. Therefore, tentatively, and subject to modification should the original documents become available for examination, it is my opinion that the following are probably carbon copies or photoreproductions, as the case may be, of documents bearing writings that conform with the writing on the original documents purporting to be Oswald's: (125) Item 13--September 11, 1959. Carbon copy of Armed Forces of the U.S. report of transfer or discharge bearing a carbon copy of a signature reading "Lee Harvey Oswald? (126) Item 18--November 15, 1959. Photocopy of handwritten account of interview with Miss Mosby. (127) Item 21--1962, undated. Photocopy of document identified as a "self-questionnaire." (128) Item 37 August 9, 1963. Photocopy of fingerprint card and mug shots taken by New Orleans Police Department, signed "Lee H. Oswald" (129) Item 39--September 27, 1963. Photograph of a page from a hotel register signed "Lee Harvey Oswald." (130) Item 40--September 27, 1963. Photographs (one of entire document and one of signature on visa application), Cuban Consulate, Mexico City, signed "Lee H. Oswald." (131) Item 41--September 27, 1963. Photograph of carbon copy of item 40. (132) Item 47--November 8, 1963. Two photographs of a letter to Mr. Hunt (one of entire document, the other an enlargement of signature). 246 (133) Item 48--November 9, 1963. Photomechanical (halftone) reproduction of typewritten letter to Soviet Embassy, signed "Lee H. Oswald." (134) Item 50--Undated. Photograph of unsigned rough draft of Item 48. (135) The photographs of the visa application (item 40) and of the carbon copy of the visa application (item 41) appear to be in the same handwriting as the other purported signatures of Oswald, as far as the pictorial aspects of form or design, slant, proportions, connecting strokes, et cetera, are concerned. Because the pictures are fuzzy, it is impossible to rule out tracing or some other method of imitative writing. (136) It is impossible to determine positively whether the letter to Hunt (item 47) is or is not in the handwriting of the same person as the other writings purporting to be Oswald's. (137) The photographs appear to be photohgraphs of a document bearing handwriting of the same person as that in the other documents purporting to be Oswald's. It is true that the signature is not typical--"Harvey" is misspelled--but that could be due to haste. If not genuine, the original from which this photograph was made is certainly a clever imitation. (138) It is recommended that. an effort be made to obtain the originals of all of the above-described reproductions so that they can be submitted to the same thorough examination, given the original documents. (139) (Question. Although they purport to be the handwriting of one Hidell, were the postal money order (item 29) and the envelope addressed to Kleins (item 30) actually written by the person who wrote the signatures and other writings which purport to be Oswald's? (140) Opinion. The original of the money order (item 29) was examined and compared With the original writings purporting to be Oswald's. I am of the opinion that the fill-ins on the face of this money order are in the handwriting of the same person as the signatures and writings purporting to be Oswald's. The writing on the money order conforms with the writing purporting to be that of Oswald on the other documents in every material way, including writing movement and rhythm (L) as well as the pictorial aspects of form or design, proportions, alinement, slant, and connections. It is also significant that the writing on this money order shows no indication of being a mere copy or imitation of the writing purporting to be that of Oswald. This money order was submitted in the original, and hence it was possible to give it a complete microscopic examination and to study it under the infrared image converter. (141) The envelope addressed to Kleins (item 30) was available only in the form of a microfilm enlargement. This is even less satisfactory than a photocopy as a basis for an opinion on handwriting. It can only be said that as far as the pictorial aspects of form or design. proportions, alinement, slant, and connecting strokes are concerned, the writing on this envelope, although it purports to be that of one Hidell, conforms with the original writing submitted for examination which purported to be that of Lee Harvey Oswald. (142) (Question. Was the diary (item 16) written from day to day, as it is dated, or was it written at one sitting? 247 (143) Opinion. While the diary was submitted for examination in original form, it was almost completely unsuitable (with the exception of p. 11) for document examination because of treatment with fingerprint developer. Little patches of ink were unobscured, but these were insufficient as a basis for a definite conclusion. From the patches of ink that could be studied, there are indications that the same pen and, ink could have been used to write the: entire diary. However, this observation is based solely on microscopic examination; no chemical tests were made or authorized. Use of the same pen and ink (particularly when, as here, a fountain pen or a dip pen, rather than a ballpoint pen, was used) is more consistent with the diary having been prepared at one time, or over a few consecutive writing sessions, than it is with execution from day to day over the extensive period covered. Concluding remarks (144) As far as original documents are concerned, the conclusion is that the signatures and writings on them which purport to be Oswald's are all in the handwriting of the same person. In those instances where reproductions of any kind were examined, it was found that the writing conformed in pictorial aspects with the writing purporting to be Oswald's on the original documents examined. Only a tentative opinion could be reached as to these reproductions. (145) Attached are two photographic comparison charts, prepared by the examiner, one showing most of the signatures reading "Lee Harvey Oswald," placed close to each other for ready comparison, the other a composite of most of the signatures reading "Lee H. Oswald" and of one signature reading "Lee Oswald." Large mural-size reproductions of these charts, suitable for simultaneous viewing by a number of persons, are being sent to the committee under separate cover. (146) The photographs on these charts were taken by this examiner, who also prepared the charts. They are reliable representations of all of the signatures depicted, and they show all signatures enlarged to approximately the same extent. FINDINGS AND CONCLUSIONS OF VINCENT J. SCALICE (147) The following inked impressions were examined and compared at the latent print section, Federal Bureau of Investigation, on June 8, ]978. (148) 1. Fingerprint impressions of Lee Harvey Oswald: U.S. Marine Corps Service No. 1653230 Prints taken by: Ogell W. Melam Date of prints: October 15, 1956 Armed Forces No. 327925D Signed:Lee Harvey Oswald (149) 2. Arrest fingerprint impressions of Lee Harvey Oswald: Dallas, Tex. Police Department Dallas No. 54018 Commission exhibit No. 630 Prints taken by: Not indicated Date of prints: November 25, 1963 Individual fingerprinted refused to sign same 248 (150) 3. Arrest fingerprint impressions of Lee Harvey Oswald: New Orleans, Louisiana Police Department New Orleans No. 112-723 Prints taken by: Arthur M. James Date of prints: August 9, 1963 Not signed by Lee Harvey Oswald (151) 4. Palm print impressions of Lee Harvey Oswald: Dallas, Tex. Police Department Left hand No. 628 Right hand No. 629 Prints taken by: J.B. Hicks Date of prints: November 22, 1963 (152) 5. Fingerprint impressions of Lee Harvey Oswald: Dallas, Tex. Police Department Commission exhibit No. 627 Prints taken by :J. B. Hicks Date of prints: November 22 1963 (153) The inked fingerprint and palm prints of Lee Harvey Oswald appearing on exhibits 1-5 are identical and are those of Lee Harvey Oswald. (154) In addition, the following latent impressions were examined and compared with the inked fingerprint impressions of Lee Harvey Oswald at the latent print section, Federal Bureau of Investigation, on June 8, 1978. (155) 6. Latent fingerpoint designated 4a recovered from brown paper container (wrapping) and developed by the Federal Bureau of Investigation. I identified it as the left index finger (no. 7) of Lee Harvey Oswald. (156) 7. Latent palm print, designated 4b, recovered from brown paper container (wrapping), developed by the Federal Bureau of Investigation. I identified it as the right palm of Lee Harvey Oswald. (157) 8. Latent fingerprint recovered from the trigger guard of a 6.5-millimeter, Mannlicher-Carcano rifle, serial no. C2766, processed at the Dallas Police Department. It is of no value for identification purposes. (158) 9. Lift from rifle (designated commission exhibit 139) from the underside of the foregrip at t. he gun barrel end of the foregrip of a Mannlicher-Carcano, serial no. C2766. I identified five characteristics or points of identity which match the lift. (159) 10. Latent palm print lifted from the underside of the gun barrel near the end of the foregrip, developed by the Dallas Police Department. I examined enlarged negatives which I identified as being identical to the right palm print of Lee Harvey Oswald. (160) 11. Palm print recovered from small cardboard box A (commission No. 641), by Federal Bureau of Investigation. I identified it as the left palm of Lee Harvey Oswald. (161) 12, Latent print (designated 2a) recovered from a cardboard box and processed by Federal Bureau of Investigation. I identified it as the right index finger (No. _0) of Lee Harvey Oswald. (162) 13. Latent palm print recovered from the bottom of a cardboard carton marked D. developed by Dallas Police Department. I identified it as identical to that of right palm print of Lee Harvey Oswald. 249 (163) 14. Latent fingerprint recovered from page 37 of the American Rifleman (June 1963), developed by the Federal Bureau of Investigation. An order blank for Klein's Sporting Goods Co. had been torn from page 59. I identified it as the right thumb (No. 1) Lee Harvey Oswald. 250 (blank page) 251 EXHIBITS* (1) October 24, 1956. Original of United States Marine Corps Enlistment Contract and Record, Service No. 1653230, signed Lee Harvey Oswald. 252 ENLISTMENT CONTRACT RECORD 253 (2) October 24, 1956. Carbon of Item 1, with an original signature, Lee Harvey Oswald 254 (3) October 24, 1956. Loyalty Certificate for Personnel of the Armed Forces signed Lee Harvey Oswald. 255 Loyalty Certificate cont. 256 Loyalty Certificate cont. 257 (4) October 24, 1956. United States Marine Corps Examination of Applicant Recruiting Officer, signed Lee Harvey Oswald. 258 Examination of Applicant by Recruiting Officer cont. 259 (5) October 24, 1956. United States Marine Corps Record of Emergency Data, signed Lee Harvey Oswald. 260 Record of Emergency Data cont. 261 (6) October 24, 1956. Armed Forces fingerprint identification card, numbered 327 925 D, signed Lee Harvey Oswald. 262 Armed Forces Identification card cont. 263 (7) October 25, 1956. United States Marine Corps Miscellaneous Information and Index Form (NAVMC 118(1)-PD 264 (8) May 8, 1958. Identification card, U.S. Forces, Japan. 265 (9) September 10, 1959. United States Passport No. 1733242, signed Lee Harvey Oswald. 266 Passport cont. 267 Passport cont. 268 Passport cont. 269 Passport cont. 270 Passport cont. 271 Passport cont. 272 Passport cont. 273 Passport cont. 274 Passport cont. 275 (11) September 11, 1959. United States Marine Corps Notice of Obligated Service, signed Lee Harvey Oswald. 276 (12) September 11, 1959. United States Marine Corps Security Termination Statement and Index, signed Lee Harvey Oswald. 277 (13) September 11, 1959. Carbon copy of Armed Forces of the United States Report of Transfer or Discharge, signed Lee Harvey Oswald, with a carbon copy signiture. 278 (14) September 14, 1959. Selective Service System Registration card, signed Lee H. Oswald. 279 Selective Service System Registration Card cont. 280 (15) September 14, 1959. Selective Service System registration certificate 281 (16) October 16, 1959 to March 27, 1962. Historical diary, 12 handwritten pages 282 Historical Diary cont. 283 Historical Diary cont. 284 Historical Diary cont. 285 Historical Diary cont. 286 Historical Diary cont. 287 Historical Diary cont. 288 Historical Diary cont. 289 Historical Diary cont. 290 Historical Diary cont. 291 Historical Diary cont. 292 Historical Diary cont. 293 (17) November 3, 1959. Declaration requesting revocation of United States citizenship, signed Lee Harvey Oswald. Purple ink; nib pen. 294 (18) November 15, 1959. Photocopy of handwritten account of interview with Miss Aline Mosby, UPI Reporter. 295 (19) 1960, undated. Political discussion, handwritten on stationery of Holland-American Line; 15 pages. 296 Handwritten Political Discussion cont. 297 Handwritten Political Discussion cont. 298 Handwritten Political Discussion cont. 299 Handwritten Political Discussion cont. 300 Handwritten Political Discussion cont. 301 Handwritten Political Discussion cont. 302 Handwritten Political Discussion cont. 303 Handwritten Political Discussion cont. 304 Handwritten Political Discussion cont. 305 Handwritten Political Discussion cont. 306 Handwritten Political Discussion Part A 307 Handwritten Political Discussion Part A cont. 308 Handwritten Political Discussion Part A cont. 309 Handwritten Political Discussion Part A cont. 310 (21) 1962, undated, Photocopy of document identified as a self- questionnarie. Original was stained and unsuitable for examination. 311 Photocopy of document cont. 312 Photocopy of document cont. 313 Photocopy of document cont. 314 (22) January 17, 1962. Affidavit of support, addressed to the American Embassy, Moscow, U.S.S.R., signed Lee H. Oswald. 315 (23) February 20, 1962. Russian script on lined paper, from "Alek" to "Marina" and "June" 316 (24) March 24, 1962. Entry papers of Marina Oswald, including a fingerprint identification card. (FBI Exhibit D-10) 317 Entry papers of Marina Oswald cont. 318 Entry papers of Marina Oswald cont. 319 Entry papers of Marina Oswald cont. 320 Entry papers of Marina Oswald cont. 321 Entry papers of Marina Oswald cont. 322 Entry papers of Marina Oswald cont. 323 Entry papers of Marina Oswald cont. 324 (25) June 10, 1962. Two-page handwritten letter to The "Worker." 325 Handwritten Letter cont. 326 Handwritten Letter cont. 327 (26) July 13, 1962. Letter to Leslie Welding Co., signed Lee H. Oswald; written on part of a page from a yellow legal pad. Blue ink; ballpoint pen. Location: 328 (27) October 9, 1962. Application for Post Office Box No. 2915, signed Lee H. Oswald. 329 Application for Post Office Box cont. 330 (28) March 8, 1963. Photocopies of a note in Russian to Ruth Paine from Marina Oswald. Location: Archives. (CE 404) 331 (29) March 12, 1963. United States Postal Money Order #2,202,130,462. 332 Money Order cont. 333 JFK EXHIBIT 509 334 (30) March 12, 1963. Enlargement of microfilm reproduction of Klein's order form for rifle from A. Hidell. 335 (31) May 4, 1963. Photograph of man with rifle and newspapers. On the back of the photograph is a handwritten notation reading "To my friend George from Lee Oswald 5/IV/63" and, in Russian, the statement "Copyright G de M." Also in Russian is writing which translated as "Killer of Fascist--Ha-Ha-Ha !!!" 336 Photograph cont. 337 (32) May 26 (1963).* Two-page letter to Fair Play for Cuba Committee. 338 Letter cont. 339 (33) June 15, 1963. Fair Play for Cuba Committee, New Orleans Chapter. 340 (34) June 25. 1963. Passport application, signed Lee H. Oswald. (35) June 24, 1963. Passport photograph attached to item 34, signed Lee H. Oswald. Blue ink; ballpoint pen. Location: Archives. 341 Passport Application cont. 342 (36) August 9, 1963. Fingerprint identification card of New Orleans Police Department, signed Lee H. Oswald. 343 CURRENT ARREST OR RECEIPT 344 (37) August 9, 1963. Photocopy of fingerprint card and attached mug shots, New Orleans Police Department, signed Lee H. Oswald. 345 (38) August 28, 1963. Handwritten letter to Central Committee C. P. (Communist Party), U.S.A. 346 Handwritten Letter cont. 347 Handwritten Letter cont. 348 (39) September 27. 1963. Photocopy of a page from a hotel register. 349 (40) September 27, 1963. Photographs (one of the entire document and one of the signature) of the original of the visa application, Cuban Consulate, Mexico City, signed Lee 11. Oswald. (Shown here is only the photograph of the entire document.) 350 (41) September 27, 1963. Photograph of the carbon copy of item 40, shown to the Select Committee staff when they met with President Fidel Castro in Havana, Cuba, with an original signature, Lee 11. Oswald. 351 (42) October (no date), 1963. Letter to the Russian Embassy. Location: Archives. (FBI D-441321 AX Q449; CE 103; JFK F-500). 352 Letter to the Russian Embassy cont. 353 (43) October 15, 1963. Employment application, with face sheet signed Lee H. Oswald. 354 (44) October 16, 1963. Employee's W-4 Withholding Exemption Certificate. 355 (45) November l, 1963. Application for Post Office Box 6225, two cards, each signed Lee H. Oswald. Blue ink; ballpoint pen. Location: Archives. (CE 792; JFK F-495) 356 (46) November 1, 1963. Receipt for key to Post Office Box (6225, signed Lee H. Oswald. Blue ink; ballpoint pen. Location: Archives. (CE 792; JFK F--495) 357 (47) November 8, 1963. Photograph of a facsimile copy of a handwritten letter to Mr. Hunt. 358 358 (48) November 9, 1963. Photomechanical (halftone) reproduction of a typewritten letter to the Consular Division, Embassy, U.S.S.R., Washington, D.C. 359 (49) July 18, 1964. Exemplar (standard) signatures and writing of Jack Ruby. Location: Archives. 360 (50) Undated. Photograph of unsigned rough draft of item 48. 361 Exhibit for identification 362 (51) Undated. Handwritten speech, nine pages. cont. 363 (51) Undated. Handwritten speech, nine pages. cont. 364 (51) Undated. Handwritten speech, nine pages. cont. 365 (51) Undated. Handwritten speech, nine pages. cont. 366 (51) Undated. Handwritten speech, nine pages. cont. 367 (51) Undated. Handwritten speech, nine pages. cont. 368 (51) Undated. Handwritten speech, nine pages. cont. 369 (51) Undated. Handwritten speech, nine pages. cont. 370 (51) Undated. Handwritten speech, nine pages. cont. 371 Two receipts for salary from the Texas school Book Depository. signed Lee H. Oswald. (FBI Exhibit 422) 372 (53) Undated (August?). Photograph of Cuban identification card, Flight 751, signed Jack Ruby. 373 Photograph of Cuban identification card cont. 374 (54) Undated. Exemplar writing of Marina Oswald, including seven slips of paper containing the writing "A. J. Hidell." location: Archives, HSCA. 375 Exemplar writing of Marina Oswald cont. 376 (55) Undated. Dallas Public Library card. 377 377 (56) Undated. Note in Russian, consisting of 10 lines of handwriting, signed, in Russian, "Alek." 378 (57) Undated. Note in Russian consisting of two pages of 11 handwritten instructions concerning the Walker incident, referred 10 as "the Walker Note." 379 Note in Russian cont. 380 (58) Undated. Certificate of Service, United States Marine Corps. 381 (59) Undated. Social Security card, 433-54-3937, Lee Harvey Oswald; unsigned. 382 (60) Undated. Complimentary card, GA-JO EN KANKO Hotel. Location: Archives. (61) Three photographs of Oswald, one with the notation on the back, "taken at Camp Pendleton Feb. 5." Located in the HSCA files, Archives (unavailable at time of publication). 383 (62) Undated. Slip of paper with the following handwriting: "The Worke 23 W. 26th St. New York, 10, N.Y. The Worker Box 28 Madison Sq. Station, New York 10, N.Y. Embassy USSR 1609 Decatur St. N.W. Washington, D.C." Location: Archives. 384 (62) Undated. Slip of paper with the following handwriting: cont. 385 (63) November 22, 1963. Photographs of fingerprint forms of the Dallas Police Department. Location: FBI. (CE 627,630). 386 Photographs of fingerprint forms cont. 387 Photographs of fingerprint forms cont. 388 Photographs of fingerprint forms cont. 389 REFERENCES (1) R. Popkin, "The Second Oswald" (New York: Avon Books/The New York Review of Books, 1966). (2) Id. at p. 63. (3) Ibid. (4) Ibid. (5) Id. at p. 66. (6) Sylvia Meagher, "Accessories After the Fact" (New York: Vantage Books, 1976), p. 360. (7) Report of the President's Commission on the Assassination of President Kennedy (Washington, D.C.: U.S. Government Printing Office, 1964), p. 319. (8) Id. at pp. 321-325. (9) Id. at pp. 320-321.