Introduction

      This paper reviews how the fragments of lead retrieved from the JFK assassination were analyzed for their elemental content three times, how the results have been used and misused, and what they really mean. Even though my professional background is in neutron-activation analysis (NAA), one of the two analytical techniques applied to the fragments, I first studied other aspects of the assassination such as the physics of JFK’s complex movements after the fatal head shot (as revealed on the Zapruder film). Later, as JFK researchers learned of my background, several of them asked me to write a description of NAA and the assassination. I put it off because it looked like a morass—the references to NAA in the JFK literature (mostly by critics) seemed terribly confused, and mostly wrong. It was not a subject that I particularly wanted to deal with at that time.
      Eventually I came across textbook of criminology[1] that described Vincent P. Guinn’s work on NAA for the House Select Committee on Assassinations (HSCA) in the late 1970s, and offered a succinct table of his most important results. These simple data, which were not presented in any of the assassination books I had read, showed the meaning of Guinn’s work with clarity. At the bottom of the table was a reference to a professional article by Guinn in Analytical Chemistry, a journal of the American Chemical Society.[2] To my great pleasure, I found that this article was also written clearly and sensibly, and answered many of my other questions. It referred to other articles by Guinn, which I assembled. Together with Guinn’s testimony to the HSCA,[3] they demonstrate just how useful and important NAA has been in helping understand that terrible event.
      At the same time, I began to realize how little these results were understood or appreciated by the assassination community. Warren Commission critics and defenders alike do not have a good grasp of NAA and its significance; discussions in their books are full of errors. Thus when prodded again by friends, I agreed to look into the subject further and to write down my findings.
      The process has been full of twists and turns. Among other things, I learned that the NAA story can’t be done justice in a few pages. A full accounting requires at least a description of the technique, how NAA was used on fragments from the assassination, how the NAA results compare with the earlier results from OES (optical emission spectroscopy), and how to draw the correct conclusions from the NAA data. I have tried to address each of these topics in this article. I hope that this work can help stimulate a serious discussion of the chemical and physical aspects of the assassination, both of which areas have been long neglected. Most of all, I fervently hope that readers will come to understand just how simple and straightforward the assassination really was, and that one of the keys to understanding it lies in forensic application of physics, mathematics, and chemistry, not in weaker types of evidence such as witness reports and testimonials. The downplaying of science in the JFK assassination, and the control of the national debate by conspiratorial interests is as tragic as the assassination itself, for it has led to nearly forty years of unnecessary confusion, frustration, and cynicism. We are lucky to have such good scientific evidence on JFK’s assassination; we have hurt ourselves by not taking full advantage of it.

[1]Richard Saferstein, Criminalistics: An Introduction to Forensic Science, Second Edition, Prentice-Hall, Englewood Cliffs, NJ, 1981.

[2]Vincent P. Guinn, “JFK Assassination: Bullet Analyses,” Anal. Chem. 51, 484A–493A (1979).

[3]HSCA I, pp. 489–567.