1. In his HSCA testimony and later comments, Dr. Guinn has argued that the FBI neutron activation tests of 1964, which the Bureau called "inconclusive," actually yielded evidence of two bullets and a match between the Connally wrist fragments and CE 399-just as he claimed his 1977 tests indicated. The problem was, according to Guinn, the FBI analysts did not know how to properly evaluate their test results.
2. Guinn has suggested that even though the FBI's numbers "appeared to bounce everywhere," the real key is the ratios. Successive tests on one sample yielded first 977 parts per million, then 676 parts per million.
3. In a recorded conversation with a researcher on March 8, 1983, Dr. Guinn amplified his revisionist position:Many years later, when I did my analysis, I went back over their results once again, and I could finally figure out what they probably did wrong. That is that their relative values, let's say a concentration of something from this sample compared to that sample - the ratio was about the same in all four of their analyses, it was just the absolute amount that they were getting that was jumping all over the place, and this is what confused them, but the pattern was still there. And if you look at these, their relative values are essentially the same as what I obtained.
Let me give you an example. Suppose I analyze two samples and I say that this one is 100 parts per million and this one is 50 par million. Okay, so the ratio is 2 to 1, right? Suppose I tried it again under a little bit different conditions, and now instead of finding 100 and 50, I find 200 and 100--It's still 2 to 1 ....
This represents a dramatic shift. At no place in Guinn's writings prior to his HSCA testimony is there to be found a single reference to ratios of elements being used to compare fragments. The paper on Mannlicher-Carcano ammunition, submitted when he testified, contained no reference to the use of ratios of elements. At no time during his explanation of the basics of NAA did he refer to using ratios for such purposes. Indeed, his testimony contains many indications that he had not previously considered the issue of ratios of elements at all:
*Guinn testified that antimony was the most important element to be considered in NAA analysis. If his new, fall-back position is correct, neither antimony nor silver nor any other single element could be more important than the others, since their ratio to one another would be the crucial factor.Guinn's remarkable statement that "you simply do not find a wide variation in composition within individual WCC Mannlicher-Carcano bullets...", would seem unnecessary. What the chemist should have said (according to the revisionist Guinn) is, "you simply do not find a wide variation in ratios of elements within individual WCC Mannlicher-Carcano bullets.
* Guinn's chronology shows a remarkable pattern of revisionism:* This scientific Never-Never Land thus becomes the best of all possible worlds, a kind of NAA nirvana, where "inconclusive" can become "unwittingly conclusive," where the FBI and Guinn can get different results but the same conclusions, and thus both be right, and where the rarified air can sustain an organism as fragile as the single bullet theory. B>
Step one - He reads the FBI test data, agrees it is inconclusive;
Step two - He performs his own tests, obtains results different from those of FBI;
Step three - He goes back and tries "a little bit different approach," invokes the importance of ratios over measured composition, a concept he had never before applied to the analysis of any ammunition, never before spoken of and never before written about, then --Eureka!-- discovers that the FBI was right (and in agreement with him) all along, although neither he nor they realized it!
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