(Testimony of Cortlandt Cunningham)
Mr. Cunningham.
oxidizing agents is so large that will react--that you cannot specifically say it was a gunpowder residue.
Mr. Cunningham.
Supposedly it is to determine whether or not a person has fired a weapon. In actuality, in chemistry it is a good indication that an oxidizing agent is present. The reagents have a valid use in a chemistry laboratory.
Representative Boggs.
Let me put the question this way. Given a dozen ordinary people in the ordinary walk of life, what would be the chance of a positive reaction on any one of these 12 people?
Mr. Cunningham.
Excellent, sir.
Mr. Eisenberg.
Has the FBI performed an experiment to determine this?
Mr. Cunningham.
Yes; we have. The early sets of tests we ran with diphenylamine. And 17 men were involved in this test. Each man fired five shots from a .38 caliber revolver. Both the firing hand and the hand that was not involved in the firing were treated with paraffin casts, and then those casts treated with diphenylamine. A total of eight men showed negative or essentially negative results on both hands. A total of three men showed positive results on the idle hand, but negative on the firing hand. Two men showed positive results on their firing hand and negative results on their idle hands. And four men showed positive on both hands, after having fired only with their right hands. That was the first test we ran.
The second test--we used people who had not washed their hands in any way. They were going about their duties during the day. Their hands were soiled. Nine people fired weapons out of 29--20 people just had the casts made.
The first person fired a revolver. Both right hand and left hand were positive. The second person fired a revolver. Both hands positive. A person fired an automatic pistol, where you would not expect to find residue. Both hands positive. Shooting with the right hand only. again one with a revolver and three people firing automatics, all positive. Shooting with the left hand only, one person with a revolver, one with an automatic, both hands positive.
Now, of the 20 people that had not come in contact with a gun--they definitely had just gone about their business every one of them showed positive tests on either or both hands. A heavy smoker, for instance, would come up positive in the area of the hand where you expect to find residues from firing a gun.
Representative Ford.
That is the hand that you use for smoking?
Mr. Cunningham.
That's correct. And I noticed you with your pipe. You are also sure to react because you touch the tobacco in your pipe. You do it unconsciously. During another test we performed recently I did not know that the diphenylbenzidine was on the corner of the cast I was trying to pick up to wash off. I just touched it, and both my fingers which had touched my cigar turned a blue color. That is how sensitive it is.
Now, of these 20 people true there were some that had one hand that did not get a reaction, but they all got a reaction. one hand or another, or both.
Now, recently in connection with the assassination we made casts--the three of us, Special Agents Frazier, Killion, and myself, for neutron-activation. How ever, two of the casts we treated with diphenylbenzidine. We obtained a cast of the left hand after firing this particular revolver four times and reloading. We obtained a cast of the right hand after firing that revolver four times, and reloading. We treated both casts, fronts and backs with diphenylbenzidine. This particular one was run on me. I washed my hands thoroughly with green soap--and the green soap, by the way, did not react because we checked it--the gauze used and the paraffin were all checked, to see if they would react, and they did not. We found numerous, numerous reactions on the casts of both hand. And I did not fire a weapon with my left hand. However, as I previously showed you, when I demonstrated how you ejected cartridge cases, all of those residues showed up, as well as, I am sure, other foreign material that the paraffin removed from my hands. And there were reactions on both hands, fronts and backs.
Now, theoretically, you should not find them on the backs over here, because I had my left hand behind me, and you would find it on the palm. We found reactions everywhere on the casts.
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