(Testimony of Joseph D. Nicol)
The Chairman.
I have no questions.
Mr. Rhyne.
No questions.
Mr. Eisenberg.
Mr. Nicol, do you have anything you would like to add before we conclude?
Mr. Nicol.
No; I think I have covered everything.
Mr. Dulles.
We want to thank you very much.
Mr. Eisenberg.
There is one further question I have.
When you made your examination, were you aware of the conclusions which any other examining agent or body had come to?
Mr. Nicol.
No. I of course was aware of the fact that tests were conducted. However, I was not aware either through the press or any other media as to the conclusions. This represents my own personal conclusions without benefit of any other knowledge.
Mr. Eisenberg.
And do you know at this point what any other body has come to in the way of conclusions?
Mr. Nicol.
No, sir.
Mr. Dulles.
I wonder if you would be willing to give us your views as to the effectiveness of paraffin tests?
Mr. Nicol.
I have used the paraffin test both in case work and in experiments, as an investigative aid. However, I have a very low level of confidence in it either as a positive or negative, as far as that's concerned.
Experimentally, as the literature well demonstrates, it is possible to fire a gun and get nothing on the hands. It is also possible to take people at random off the street and test them with the reagent which is not specific for powder and find all kinds of reactions. And while there are some "experts" who--and I say that with quotes- who allege that they can differentiate one product from another, actually the end product of the oxidation of diphenylamine is a definite quinoid structure, which has only one blue color, and I am not sure how they make this differentiation. I cannot do it.
I have used it as an investigative aid with positive results if and when I find in the cast a particle of powder that I can definitely identify as powder--not just simply the reaction, but something I can take out, put it under the microscope and I can say this is a particle of powder. Then I will say that this hand has been in the presence of the discharge of a weapon.
Mr. Dulles.
You do not need a paraffin test for that, do you?
Mr. Nicol.
I don't think so. I think if you actually examine the subject's hands, you probably can find that. Although as a rule in the laboratory we do not see the subject, and so this is the medium by which we get a look at the surface of the hand.
Sometime ago in Los Angeles a series of experiments was conducted whereby--and this was on shooting victims, including only those where they could be certain by other investigative means as to the exact status of the case. One of the technicians placed the paraffin on the hand. This was presented to the other technician who had no knowledge of the case whatsoever. And that I guess must have included both the controls of non- shooting victims as well as shooting victims. And the net result was if this fellow almost flipped a coin he could be in the ball park as far as whether or not this person had actually fired a weapon.
It just is not particularly accurate.
I might go further to say that there have been several cases in which I would say a fair amount of injustice was done to the defendant or the suspect in the case simply because people have gone overboard on the application of the paraffin test.
It is one of these areas in which everyone would like a nice test. It would certainly be beneficial. But it is not one in which a competent technician places much confidence.
Mr. Dulles.
I understand that pipe smokers are quite likely to get caught on these, on these tests.
Mr. Nicol.
Or someone who strikes a kitchen match, or in the spring, a man fertilizing his lawn. A man working in the meatpacking industry, where they preserve meats with nitrates, might also have difficulties. Certain of the com mon things, such as urine, I think can be discounted, because the diffused
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