THE COURT: Call your witness.
MR. SMITH: Your Honor, the Defense calls to the witness stand, as its first witness, Dr. Vincent P. Guinn.
(Whereupon, DR. VINCENT P. GUINN was called as a witness, duly sworn, and testified as follows:)
MR. SMITH: Take the witness stand, if you will, please, Dr. Guinn.
D I R E C T E X A M I N A T I O N 2:22 p.m.
BY MR. SMITH:
Q State your name for the record, please, sir?
A Vincent P. Guinn, G-u-i-n-n.
Q Mr. Guinn, where do you live?
A In La Joya, California.
Q How long have you lived in California?
A All my life except for about three years when I was in Massachusetts.
Q Mr. Guinn, what do you do?
A I am a professor of chemistry at the University of California at Irvine.
Q How long have you served at the University of California in that capacity?
A Something over nine years.
Q Prior to that period of time, what did you do, sir?
A The eight years before that, for an eight year period, I was a technical director of the Activation Analysis Program at General Atomic Company, which is a nuclear company based in San Diego, California.
Q Dr. Quinn, where did you get your training in chemistry, if you did get chemistry training?
A Yes, bachelor's and master's degrees at the University of Southern California.
Q What years was that?
A Bachelor's was in 1939; master's, 1941; and the doctor's degree, Ph.D. at Harvard University in 1949.
Q And did you do any work at the Oak Ridge Institute -- in nuclear studies?
A Yes. Shortly after finishing at Harvard, I was working with the Shell Development Company, as a research chemist. I started work in what is called Radiochemistry or Nuclear chemistry. I commenced that by taking training at the Oak Ridge Institute of Nuclear Studies.
Q What research experience have you had?
A Well, I was for a number of years at the Shell Development Company. I was head of the Radiochemistry group. As I mentioned, at General Atomic, I was technical director of the Activation Analysis Program. All of this involved research. Then, of course, at the University of California, it involves research and teaching, both.
Q Dr. Guinn, are you a member of any honorary societies or professional societies?
A Yes. Many of them common to this field -- the American Chemical Society, of course. I am a fellow of the American Nuclear Society. In the forensic field, I am a fellow of the American Academy of Forensic Sciences, and a member of the California Association of Criminalists, and member of the Forensic Science Society of England.
Q Dr. Guinn, would you state whether or not you have done work in the field of neutron activation analysis?
A Yes, that has been my principal area of research for -- I'm not sure how many years -- something over 20 years, anyway.
Q And have you done work in forensic neutron activation analysis?
A Yes. Some of the forensic applications I first commenced research in 1962, 17 years ago, in that particular branch of it.
Q Would it be fair to say, Dr. Guinn, that you were one of the pioneers in neutron activation analysis and relating it to courtroom work?
A Especially the latter, one of the earliest people in the forensic applications. The development of the method itself started much earlier, but was relatively slow in growing until about the time that I and others became active in the field.
Q When did the concept of neutron activation analysis actually begin to be applied in the courtrooms in America?
A The first actual court case was in 1964. One of the cases we worked on was presented in court early that year.
Q Have you testified in courts across America in neutron activation analysis?
A Yes, I've testified in a rather large number of cases. I've testified in 13 states, Canada, and oddly enough, Korea.
Q Would you state whether or not you have done any work in the field of neutron activation analysis with respect to investigating the Kennedy Assassination.
A Yes, I just last year testified before the House Select Committee on the assassinations, on the work that I did just prior to that, on all of the bullet lead samples involved in the President Kennedy Assassination.
Q Have you published in the field?
A In what?
Q Have you published in the field of neutron activation analysis?
A Yes. I have roughly 180 publications in the field of activation analysis.
Q How about in the field of forensic neutron activation analysis. Have you published in that field?
A Yes. Of the 180, something over 50 are in the forensic field -- 53, as I recall.
Q Has any person who is active in the field of neutron activation analysis published more than you have either in forensic neutron activation analysis or the other uses of the art of neutron activation analysis?
A Not to my knowledge.
Q Have you testified for the prosecution and for the defense?
A Yes, for both.
MR. SMITH: Your Honor, we submit that Dr. Guinn is an expert witness specializing in the field of chemistry and neutron activation analysis. We tender him into the court as an expert and we also tender him to the prosecution for examination on that, if they wish to do so.
MR. MURTAGH: No, sir.
THE COURT: Very well.
MR. SMITH: Thank you, Your Honor.
BY MR. SMITH:
Q Dr. Guinn, before we get into what you actually did in this case, I would like to ask you, sir, to tell the jury what neutron activation analysis actually is. We have already had some testimony. Would you tell us how you would describe neutron activation analysis?
A Yes. The simplest definition is to say,that it is a nuclear method of elemental analysis. What I mean by that is that it is a method that you can analyzer essentially any kind of material. It doesn't make any difference whether it's metal or wood or cloth or hair, or any physical material.
You can analyze that sample that you may want to investigate for various elements -- not compounds -- but elements. It is different from other methods of chemical analysis in that it employs nuclear reactions as opposed to chemical reactions.
It can, as a result of that, frequently be used nondestructively, which is an advantage in the sense that you do not destroy the samples that you are analyzing. Its principal virtue, as practiced in recent decades now, is that it is extremely sensitive.
You can detect and quantitatively measure most elements in amounts or concentrations much further down, much lower, than can be detected at all by most other methods of elemental analysis. So, it is extremely sensitive.
That means that many samples you can analyze nondestructively and see in the sample many elements, whether you knew they were there before or didn't, whether you were looking for them or not. They can show up and then you can identify them, and you can measure them quite quantitatively.
Q What kind of equipment is involved in the analysis you described?
A Well, one of its limitations, you might say, is that in order to achieve all these fine sensitivities, you need to have a nuclear reactor -- not a power reactor, but a research-type nuclear reactor. Those are not as scarce as you might think. There are probably 100 of them in the United States, for example, capable of doing this type of work.
Q What other equipment do you need?
A When you proceed to analyze a sample, you put it into the reactor, where in or near the core of the reactor it's bombarded with a tremendous number of neutrons, which are sub-nuclear particles.
Some of the atomic nuclei of the elements you are looking for will capture the neutron. That doesn't change it to a different element, but it, in most cases, makes it a radioactive isotope of the element.
So when the sample comes out, normally it doesn't look any different than it did when it went in. Except that if you were to wave a Geiger counter or something around it, you would find that it is radioactive.
Now, to do a real analysis of it, you can't just use a Geiger counter -- that just says it's radioactive but it doesn't say what's there. So, you use a considerably fancier piece of electronics, which is called a gamma ray spectrometer. That looks at the gamma rays being emitted by these different kinds of radioactive elements.
It shows them essentially on a graph and you see peaks -- you see a peak there, which tells you what particular radio isotope it is, and you can measure the size of the peak and therefore make a quantitative analysis.
Q Dr. Guinn, did you bring any slides with you today of the equipment that is involved in the analysis?
A Yes; I have just a few slides here -- just four of them that may give a little better picture than my words do.
Q Can you use those slides to illustrate your testimony?
A Yes -- to describe what I was just trying to describe in words there --
MR. SMITH: (Interposing) We would request permission from the Court to dim the lights in the courtroom and have Dr. Guinn show the slides. We have arranged, I think, to have the lights dimmed, and we would like to do that at this time.
THE COURT: Okay. Proceed.
MR. SMITH: Thank you, Your Honor. I would like to ask Dr. Guinn to come over to the screen if that will not interfere with the jury's view so that he can use the pointer and point out the equipment portrayed.
THE COURT: Go right ahead.
BY MR. SMITH:
Q Dr. Guinn, if you will please use the first slide to explain to the jury the kind of equipment portrayed and try not to get in the way of the jury.
A It may be a little bit difficult. Maybe I will have to kneel down there. This is a view in our reactor laboratory at the university. The reactor is down in the basement of our building. You just see a corner here of the pool.
I will show you what the reactor itself looks like in a moment. Down in the pool is the core of the reactor -- in a deep pool of water. The apparatus that you see here -- you will see a close-up in a moment -- is one of our gamma ray spectrometers that we count the radioactive samples with.
This room at the back is a place where we can put samples in a tube and you can shoot a sample into the reactor in about three seconds, leave it in there for a number of minutes if you wish, and then it will shoot back out in about three seconds in a matter much like, you know, some stores I think still use to send change or whatnot around inside of a store.
This just gives you a little bit of the physical layout of our laboratory. When the reactor is running and you are standing up above the pool of water looking down into it, this is what you see. The blue glow is caused by the radiation interacting in the water. It is called Cerenkov radiation.
The core of the reactor is not very large. This is only about a foot and a half across in diameter. It's about two feet tall. You are looking down at it through about 16 feet of water which makes it perfectly safe to be working up above it. Otherwise, there would be too much radiation.
There is a rotating rack inside of here that we can load and unload from this tube and that way -- it rotates around -- we can irradiate many samples simultaneously where we want to give longer radiations for hours or so.
Those are the main ingredients. The other things are the control-rods, et cetera that turn it on and off and regulate the power. This is a close-up of that particular gamma ray spectrometer. There is a shield around it here. inside of that there is a germanium-type detector.
You put the radioactive sample inside of the shield on top of the detector. Then you turn it on when you are counting. You can see the spectrum building up here on the oscilloscope display. When you finish, you normally transfer all the data because you actually have a plot of the gamma ray spectrum -- a 4,096-point plot, and you put all the data on the magnetic tape until we are ready to look at it in detail. In the meantime, you can go on to the next sample. When you are finished, you want to read all this out. You read samples back through one at a time through the PDPA computer to sum up the areas of peaks and so on and they are all typed here on a teletypewriter.
I mentioned before that the big advantage of this method over other methods is its extreme sensitivity. This won't mean a thing to you, unless I mention these are just the chemical symbols for the different elements.
There are limits of detection. The smallest amount we can detect listed there for 75 elements, which means it is pretty good for most of the elements in the Periodic System. Under sort of typical conditions, this is the smallest amount we can detect of the element, already expressed in micrograms.
A microgram is a millionth of a gram. There are a few elements that we have tremendous sensitivities for, where we can detect and measure even a millionth of a millionth of a gram. Typical ones are in the middle here -- more like a thousandth of a microgram or a billionth of a gram in other words.
And even some of the rather poor ones we can still go down as low as a microgram or so. So that just gives you some feeling for the fact that it is an extremely sensitive method in that it does apply to a large number of elements. That is all the slides.
MR. SMITH: Thank you, Dr. Guinn. Yes, sir; you can return to the witness stand. Thank you, sir. We are ready for the lights again.
BY MR. SMITH:
Q Dr. Guinn, did you perform any analysis of any kind of samples for the Defendant, Dr. Jeffrey MacDonald, in this case?
A Yes; samples were supplied to me, which are latex rubber samples, and there were essentially two groups of them, three of them classified as evidence samples, eight of them as exemplar or comparison type samples, and I did analyze them in my laboratory by neutron activation analysis with the equipment that you saw there.
Q All right, sir, when did you receive the samples for analysis? Do you recall that?
A Yes; July the 2nd of this year.
MR. SMITH: There must be a way of turning this off, Your Honor.
THE COURT: How about pulling out the plug?
MR. SMITH: We tried that and it didn't work.
BY MR. SMITH:
Q Dr. Guinn, if you will, describe for the Court and the jury the method you used to analyze the samples you received by the Defense in this case.
A Yes; well, they are handled much like any types of physical evidence are in criminal investigations. The first thing that you do is to look at the samples, being very careful to look at them just one at a time so there is no possibility of mixing them up or anything -- look at them one at a time with just some magnification that they are solid samples to see if they appear to be what they are supposed to be and they don't appear to be obviously dirty or muddy or whatever so you get some general information of the condition.
The next thing that you do with solid samples that can very well have surface contamination -- you don't know what's -- maybe people have picked them up with their fingers, for example, which will put some oil and some salt on them right away -- and they may have picked up dust on the surface, so you go about to clean them -- clean them in a way that will clean off external surface-type contamination but not run the risk of actually dissolving out anything that's inside.
In this particular case, I used the same technique that we use on hair samples which are when they are involved in criminal cases, and this is alternate washings with very high purity water and very high purity acetone -- the water taking away water-soluble things like salt; the acetone taking away oily or organic materials -- and at the same time the particles are not taken away.
After you have cleaned the sample, then, of course, they have to be dried and, since some things are sensitive to temperature, you usually air dry them just at room temperature in a -- depending on the material -- in a dust-free location and then you have to weigh the samples on an analytical balance so you know how much you are dealing with, and finally, put it in a little, specially cleaned, polyethylene container which is the one that goes into the reactor.
Q All right, continuing, if you will, describing what you did in this case, tell us what you did next.
A The first thing I did with these samples, after preparing them already for irradiation, I gave each of them -- I did these one at a time now -- gave each of them a one minute -- 60 second -- irradiation in the what's called the pneumatic tube, the high speed tube there, position in the reactor. After the sample came back out, after its irradiation, I opened the vial, transferred it to a fresh vial because, even fairly pure polyethylene has some impurities in it and I didn't want to be measuring those -- I wanted to measure what is in the sample -- so each one was then transferred to a fresh container, already labeled, then put into -- and that was one minute allowed for that -- then put in the counter that I showed and counted it for one minute, and the spectrum was stored.
The next sample was treated the same way -- went right down the series.
Q Now, Dr. Guinn, you indicated that it took, I believe you said one minute to get the samples out of the reactor before you started counting them; is that correct?
A It didn't take -- it only took three seconds to get it out, but we deliberately allowed one minute of decay to also give time to transfer it to the fresh container.
Q Will you describe what you mean by the word "decay"?
A Yes. All the radio isotopes -- radioactive isotopes -- are decaying. That is, they are emitting radiation and changing from one isotope to another in the process, so while you are looking at them, they are disappearing. Different isotopes disappear at tremendously different rates. There are some radio isotopes that have what we call half-lives of millions of years. In other words, it might take a million years for half of them to have gone away by decay. There are others that we deal with that will decay away in just a matter of seconds. One of the things that I measured in these samples was silver. In the radioactive silver that we measured, it has a half-live of 24.4 seconds, so you have to move fairly quickly or else it is all gone.
Q Would it be fair to say then, Dr. Guinn, that if you don't move quickly, you will lose maybe some of the elements or at least evidence of some of the elements which could be present in the sample?
A Yes. Whenever you,are analyzing samples where you are trying to find as many elements as possible and which is often the case like hair analyses and so on, it is essential that you use conditions where you work quickly so that you see those elements that only form the short-lived isotopes. Then afterwards, after those are all gone, then you can re-irradiate the samples but now for a longer period of time so that you build up more of the long-lived things and then you deliberately wait a longer time like an hour maybe so that all these short-lived things that you have already looked at will go away so they don't clutter up the spectrum, and then you count for a longer period of time and then you may count them again a day later and again a week later. In this way, you see more and more elements.
Q Yes. I interrupted your description. I believe you have indicated that you irradiate the samples for a minute and then retrieve them from the reactor. What did you do next?
A Well, during the one-minute period where we transferred them to a fresh container, then we were ready to start the count. Then, each was counted for one minute and the data stored while we went ahead with the next one.
Q What did you do next?
A Then, as soon as I had gone through the whole series, then I took the data for each of them and searched it. The way we do that -- on the spectrometer, I showed there was an oscilloscope where you can see the whole spectrum there with peaks superimposed on it now with a curving background but various size peaks at different locations, but then what you do, you can expand that scale electronically so it is like stretching it way out and then you just start at one end and you search through it with an illuminated period, and as soon as you come to a peak, you see it now spread out -- you can actually see the shape of the peak -- and then through the computer, you just say what is the energy of this peak and it prints it out for you. That tells you what the radio isotope is and you go ahead and look for the next peak.
What we did here is just go through -- I just went through and searched for all of the peaks that I could find and identified them all and then printed out the whole region, so we have the numerical values to work with -- data -- numerical data.
Q After that, would you state whether or not you irradiated the samples again?
A Yes. Actually, the irradiations were done on July 10th -- first, the short irradiation and then a few hours later, a one-hour irradiation this time in that rotating rack so we could put them all in at the same time instead of doing one at the time. They were irradiated then for one hour this time instead of just a minute and then deliberately allowed to decay for one hour and again transferring them to a fresh container. Then, each sample was counted for -- I think the first time was a one -- minute count again because they were fairly accurate and the data obtained and stored the same way.
Then, I counted them again the following day so they got roughly 24 hours decay -- counting them a longer period this time because they weren't so radioactive now and got all of that data. Then, finally, a week later -- actually, it was eight days after the activation, I counted them again for a longer period of time yet and processed the data the same way.
Q Yes, sir. Dr. Guinn, you used the word "exemplar" from time to time. What does the word "exemplar" mean?
A The way it is used in this connotation usually means comparison samples. You would want to compare evidence samples with some other kinds of samples of known origin. You knew who had manufactured it, let's say, or in the case of natural materials, you know for sure that it was removed from somebody -- some particular person's head -- to compare with the unknown ones which perhaps were associated with the scene of the crime.
Q All right, sir, so would it be true then that you used two kinds of samples -- one being evidence and the other being an exemplar to compare the others with?
A Yes, sir. There were actually eight exemplar samples and there were three evidence samples.
Q Yes, sir. Now, Dr. Guinn, would it be a fair statement if I said that the more elements you find in the samples, the better chance there would be that you could make a good comparison?
Q Well, it depends on what you mean by a "good comparison." If you are trying to establish that the, let's say the evidence samples, had the same origin, let's say we are talking here about manufacturing origin -- that they really were manufactured by the same manufacturer as the exemplars and in the same production run, et cetera, then, it doesn't do much good to just measure a few elements because you might find many different manufacturers would have about that much of this element or that element; but the more elements that you can detect and measure, the less likely or less probable is it that two different sources could magically turn out with just almost indistinguishable concentrations of all these elements.
Q Dr. Guinn, how many elements did you find in the evidence samples?
A I think I found 11. I can double-check that. Eleven elements, yes, sir...
Q How many elements did you find in the exemplar? That is,the samples that you were comparing the evidence samples with.
A Ten of those 11, I found in those also.
Q Now, did you record any numbers that would help us to understand the concentrations of those elements?
A Yes, because it is not a significant thing just to say that I detected this element in this sample and the same element in this one. You might have 100 times as much in this one as this one and that is equally important. You must measure the concentrations because if they really had a common origin, they will not only show the same elements, but they will also show pretty closely the same concentrations.
Q How do you express concentrations? By what words do you use to express that?
A Well, I think the most common way for most things -- of course, if you are dealing with higher concentrations, it would be to record them in percent -- weight percent -- and say this thing is three percent or 4.2 percent or whatever it is. Here, the concentrations, in most instances, are much lower than that. We can see things that are very low. In the common unit of measurement, there are parts per million by weight. One part per million means that you have one part in a million parts by weight of the overall material, so a part per million is the same as .00001 of one percent. It is .00001 percent. That is one part per million.
Q Directing your attention, Dr. Guinn, to the evidence samples first, what elements did you find in the evidence samples?
A In the evidence samples -- sodium, magnesium, aluminum, sulphur, chlorine, calcium, manganeze, copper, zinc, silver, and I will say gold although it is right on the borderline of detection.
Q And what elements did you find in the exemplar?
A Exactly the same except there was no silver detectable, and again the gold was right on the borderline of detection. It was there but you couldn't measure it accurately -- but no silver. I could not find any silver in any of the exemplar samples.
Q In comparing those samples, Dr. Guinn, the exemplars in the evidence, are there any particular elements that you feel you could express better by the use of a chart; that is, to show the differences between the exemplars and the evidence?
A Well, one could take the numbers that I submitted in my report and show them on a drawing. Some on these boards, for example, might be a little easier than just talking about the numbers, yes.
Q I wonder, Dr. Guinn, if you would then come down from the witness stand and go over to the easel. May I approach the witness, Your Honor?
THE COURT: Yes.
BY MR. SMITH:
Q Using any kind of marker that you may have with you that you think would be helpful, and show the jury the differences in any of the elements that you found in the exemplars and the evidence which you think would be useful to the jury -- that is, in seeing the difference?
A All right, fine. Well, I will pick one of these, which happens to be the first one on the list there: sodium, a very -- relatively common element, and so you do see it in lots of things.
Q If you could speak a little more loudly, please, Dr. Guinn?
A All right. It is a little hard for me to print with this thing wobbling, but if you can see this all right, I am just going to show you what the numbers look like for the element sodium.
Now, in this scale here I am just going to plot parts per million -- PPM -- of sodium found in the exemplar samples. I am just going to give you the average value with the -- showing somewhat the spread of the value, since not every sample is exactly the same.
And the exemplar samples -- let's see -- I'll have to put a scale on here. Let's see, can I do it this way: if this is 100, 200, 300, 400, 500. You probably can't read back there, but I'll point them out a little better. If we put a scale this way, going from zero parts per million to 500, we look at the exemplar samples. They average 114 right here; but there was a spread of values, plus or minus about 21, so that would take it up to about 135, and down to about 90 something here.
So we can say that essentially all or most of the exemplars -- these are the exemplar samples -- fell in this range here.
Now, the three evidence samples that I also analyzed for sodium -- they also showed sodium, but the mean value here -- average value -- was 327, about here; but more spread in those values, plus or minus 113, so that would take this one down to about 220.
I will have to show it as a broad distribution here, and up to about 400 something here. They showed a wider spread of values.
Q And that is the evidence samples?
A These are the evidence samples.
Q Is there any other element that you think maybe you could select that would illustrate to the jury the difference in the concentrations of elements in the evidence in the exemplars?
A Yes, I'll put another one on; but let me just point out here that there are some elements where when you do exactly what I did here -- just readjusting the scale because it is for a different element -- the two distributions overlap with one another. There is no gap in between them.
What that really means is they are very closely the same, and we really can't say whether they are different and the same -- different or the same -- they are so close together.
But when there is a sizable gap in between, you can say there is a very measurable difference between this one and this one. The values, by the way -- the mean one here -- was 114; and this was 327, something two-and-a-half or so times that.
All right, I will take another one that shows a sizable difference here. Magnesium would be another one you could use. I won't do this for all of them, so don't worry about that. I'll just do it for a few illustrative ones.
Now, magnesium, the concentrations are quite a bit higher and they go out here to a couple of thousand, so I have to adjust my scale accordingly here, and see if this is about -- this time this is zero, and this is 1000 parts per million, and this is 2000 parts per million.
The concentrations of magnesium are considerably higher in general in these samples than of the sodium. All right, the exemplars -- this time it is the other way around. The exemplars have the higher concentration.
They average 2130, which is out about here somewhere, plus or minus enough that it will go off the scale on my little drawing a little bit here. I will show it about like this.
These are the exemplar samples this time, and they average 2130. The evidence samples for magnesium, however, only average 330, which is way down here, plus or minus spread values there of 79, so that goes up about -- let's see, 330 -- they cover about this range.
Now, these are the evidence samples, and the average is 330. Now, here the difference between the two is far wider than it was for the sodium, so very clearly the exemplar samples have a lot more magnesium by a factor of six or so times as much as the evidence samples here.
Now, I don't know whether you want to draw any more or not. One can draw this for several more.
Q Why don't we, Dr. Guinn, have you to describe from the witness stand the differences you observed in the exemplars and evidence samples, and if you would do that now, I think it would help. What differences did you observe in the exemplar samples and the evidence samples, other than the sodium and magnesium you have indicated on the chart?
A All right, I will first of all mention the ones where there seemed to be a quite measureable difference there. Chlorine is another one where the evidence samples have about -- average about 2.1 times as much chlorine as the exemplar samples, which if you plotted in the same way, again, there would be a sizable gap in between.
Copper, there is a large difference. The evidence sample is running 4.6 times as much copper as the exemplar samples.
Zinc, the difference is not so large, but there is so much of it to measure that I could measure it very precisely, and the difference in the two is quite significant. In this case the exemplars had 1.5 times as much on the average as the evidence samples.
And then, of course, silver was there and could be measured in the evidence samples, and I couldn't measure it at all in the others, so I can't express it as a ratio because I don't know what the other one is. It is below the limit of detection.
Then there were a few elements that, as I mentioned, if I drew them the same way the two groups, if I would do it, each with this width are close enough that they would overlap, and therefore we would say, "Well, those are about the same in the two different batches of material."
Aluminum would be one of those. Sulfur would be another. Calcium and manganese would be the others. So there are some that are nearly the same, and there is a larger number that show sizable differences.
Q You were requested to give an opinion as to whether the evidence samples could or might have been made by the same manufacturer As the exemplar samples; is that correct?
Q And based on your analysis and your efforts in this regard, did you arrive at any conclusions or any opinion as to the answer to that question?
A Yes, I did.
Q And what is your opinion as to whether the evidence samples could or might have been manufactured by the same manufacturer as the exemplar samples?
A As I stated in the written report, there is not, to my knowledge, a broad background of information in the literature, or in my own experience or anybody else's experience, about what all different kinds of rubber latex samples look like when they are analyzed this way.
So, we don't know all samples, all different manufacturers, like we do on some other materials. But, interpreting these results from the background of having looked at many other kinds of manufactured materials, where the manufacturer is trying to make a uniform product, it usually has quality control, et cetera.
They control things rather well, in general, and so a particular kind brand that they make for a long period of time, even one production batch after the other -- if it's a batch process -- will look very, very similar. You really couldn't distinguish one from the other.
You can distinguish his product from some other manufacturer, because he will have different sources of raw materials, which will introduce different trace impurities. Most of these elements here are not added deliberately by the manufacturer. They come as impurities in the things that he is adding.
So, if a given manufacturer then changes either his method of production significantly or the source of supply, of one or more of these raw materials, then there will be a change in composition that you will see.
Now, with that kind of a background that we have applied to many kinds of manufactured materials, I would say that if we compare two, or in this case, two groups of samples of latex rubber, and we find differences such as this, and repeated with several elements, I would say it would be extremely unlikely -- I can't say it's impossible -- but it is extremely unlikely, that those samples -- the exemplars and the evidence, in this case, could possibly have been made by the same manufacturer in the same production batch.
Very, very unlikely. The members are too far apart. If you say, well, could it be made by the same manufacturer -- well, who knows. Maybe in one year he might be making it with a sufficiently different thing -- there might be those differences -- but that would be productions far apart, even though they happened to be by the same manufacturer, accidentally.
Q Would it be fair, then, to say, Dr. Guinn, that it is your opinion that it is unlikely that these evidence samples and exemplar samples were even made by the same manufacturer?
A I would say it was unlikely -- at least in any reasonable period of time.
Q Now, Dr. Guinn, have you had an opportunity to look at the reports submitted by Dr. Hoffman, for the Government, on this same subject?
A Yes, yes; that's Mr. Michael Hoffman.
Q Yes, sir. Did you observe, Dr. Guinn, that Mr. Hoffman found four elements -- that is zinc, sodium, copper, and gold.
Q Is there any explanation, Dr. Guinn, for the difference between the number of elements you found and the number of elements found in the Government's report?
A Yes, very definitely. In the longer radiation lung decay, I found the same four elements. The other elements are all ones that form short-lived species, which he quite apparently didn't look for. It would have been possible for him to do, but apparently he did not.
I said he could have looked for them, but he did not.
Q Now Dr. Guinn, had you examined any numbers that were given by Mr. Hoffman in court concerning zinc, sodium, copper and gold?
A Yes, I have the numbers jotted down here.
Q And were those numbers furnished to you by me?
A Yes, uh-huh.
Q Based on those numbers that were supplied by Mr. Hoffman here in the courtroom, do you have an opinion -- not using your numbers, but his numbers -- as to whether the evidence samples and the exemplar samples could or might have been manufactured by the same company?
A Yes, I do.
Q What is your opinion?
A My opinion is that just looking at the numbers that he submitted, I would come to the same conclusion -- that it would be extremely unlikely that the evidence in the exemplar samples were made by the same manufacturer.
His numbers show the same large differences that mine do.
Q In other words, using his figures, would you reach the same opinion that you have rendered in the courtroom today, based on your own figures?
A Yes, I can reach that conclusion more firmly with mine because I have more elements. But the situation, so far as it goes there, is the same. The gold figures don't help a great deal in his case either.
His copper figures show the same trend, although I might add that his copper numbers are erroneous. It is a more complicated thing to determine that than he apparently realized. The sodium values show the same thing -- there is much more in the evidence samples than there is in the exemplar sample.
They say the same as mine do, except that in a couple of his samples, quite clearly, they manage to contaminate, such,as maybe by picking it up with their fingers because they have gross amounts in two cases. The zinc numbers are generally in line with what I find.
Again, the exemplar in that case being something like twice what the evidence samples are.
Q Dr. Guinn, you indicated that one of the merits of this approach to analysis is that the evidence is not destroyed; is that correct?
A That's correct; yes.
Q I take it -- I have what you are looking for right here.
A I was wondering whether it evaporated.
Q I take it that you did not, then, destroy the evidence you analyzed?
A No. The samples are there. They weigh the same, they have the same composition they did before.
Q Could these samples be reanalyzed if anyone wished to use them for reanalysis now?
A Yes. All the radioactivity that was generated in the samples is gone except for just a trace of the long-lived radioactive zinc, just a little bit of that.
MR. SMITH: Your Honor, I would like to have this marked for identification and let me get the number on this chart also, if it would help him. This chart is Defendant 25; that should be, I believe, Defendant 57; is that correct?
(Defendant Exhibit Nos. 56 and 57 were marked for identification.)
MR. SMITH: Your Honor, we offer into evidence the chart which Dr. Guinn has prepared from the witness stand as Defendant Exhibit 56. We offer into evidence the samples which Dr. Guinn used in making his analysis, as Defendant Exhibit 57. That is all the questions we wish to ask of this witness, and we would now turn him over to the Government for cross-examination.
(Defendant Exhibit Nos. 56 and 57 were received in evidence.)
THE COURT: Any questions?
MR. MURTAGH: Yes, Your Honor.
A few. I wonder if I might request of the court that Dr. Guinn be allowed to continue supplying the number values that he was doing before he began to testify. It would speed up the process.
THE COURT: Just ask him the questions.
C R O S S - E X A M I N A T I O N 3:08 p.m.
BY MR. MURTAGH:
Q Dr. Guinn, could I hand you back these two pieces of paper.
A Yes, I will continue copying if you would like. It will take quite a while, however, I may caution you -- if you want to do it during recess.
MR. MURTAGH: Your Honor, I feel that in order to cross-examine effectively I do need the values. Why don't we just go ahead for this one.
THE COURT: For the five samples that he did not give values on?
MR. MURTAGH: Yes, Your Honor. My question is directed more toward the eight exemplar samples and those values and then subsequently the evidence.
THE WITNESS: I have all the numbers here.
THE COURT: I am referring to elements. I thought he gave us six and he had eleven.
MR. MURTAGH: Yes, sir. It is the additional ones.
THE COURT: The additional five.
MR. MURTAGH: Your Honor, at this time we would like to mark Government Exhibit 1151 for identification.
(Government Exhibit No. 1151 was marked for identification.)
THE WITNESS: Okay. You took the other sheet back; did you?
MR. MURTAGH: Yes.
THE WITNESS: These are all the exemplars.
MR. MURTAGH: Let me give you one with the evidence.
BY MR. MURTAGH:
Q Dr. Guinn, directing your attention to the chart on the easel which I believe has been marked as Government 1151, I ask you to take a look at that, sir, and tell me if you recognize it?
A I would have to compare the numbers one by one. But they look offhand to be about the average values, for example, the ones that I plotted plus or minus this one and so on. This is wrong. Put another zero after the decimal. After the decimal it should be .0001.
Q Okay. Where should I put it, sir?
A Well, insert it in between those two zeros.
Q All right. Now is it correct?
A Something got left out here. Something that is supposed to be "nondetected." It says "nondected."
Q I am sorry.
A I will check the numbers as we discuss them. But as far as I can tell, they are a copy of my report.
Q Okay; thank you, sir.
THE COURT: Let's let him assume that that is what they are.
MR. MURTAGH: Yes, sir.
THE COURT: And if you find any difference, of course, you can say so.
BY MR. MURTAGH:
Q Dr. Guinn, if I could ask you to explain how you came by the values which you placed on the chart? Do you understand my question, sir?
A Yes. Each sample was analyzed for each of the elements. So, for example, the exemplar samples -- there were eight different values for sodium, because they are not all exactly the same. The average value or mean as we call it was 114. If you take the average of the eight values, you get 114. If you see how much they scatter above and below that, there is a regular statistical method of doing that which calculates what is called the standard deviation. And that is what the plus or minus 20 means.
Statistically that means that approximately two-thirds, about 67 or 68 percent, of the values fall within the range of 114, plus 21 or that high are as low as 114 minus 21. Then a smaller number can be a little beyond that or a little in either direction. That is what the plus or minus means in each case.
It is not the measurement precision for an individual sample, which is what I just gave you there, because I gave you the individual ones there. This is the average of all eight.
Q Okay. Now, let me ask you with respect to the individual samples, and since we are talking about sodium, let me ask you about exemplar number one and exemplar number three. Would you tell us, please, sir, what your actual reading was for number one and number three?
A Yes. Exemplar number one had 145 uncertainty. That is plus or minus 5 parts per million of sodium, and exemplar number three had 91 plus or minus 3 parts per million. In other words, they did not have exactly the same within the measurement precision.
Q So, would it be accurate to say that as between number one and number three -- are those the two samples with the greatest spread, if you know, sir, on that?
A Yes. The 91 is the lowest one. The 145 is the highest; yes.
Q Okay. So, we would be talking about an actual difference in reading of some 34; is that correct?
Q I am sorry; 54. Okay. Now, with respect to magnesium, which I believe was the next element you talked about, you indicated that for the exemplar you have a value of 2130, with a plus or minus of 570. Would that mean that you have a possible spread of 1,140?
A What do you mean, twice that value?
A Well, if you take twice that, that is a so-called two sigma one, and that would mean that it would be the statistical possibility that if you had enough samples that 5 percent could be -- 2 1/2 percent could be beyond twice that number added on. Five percent could be beyond twice that number subtracted from it. Statistically that is what it means.
Q Well, I guess what I am asking you is is it possible that you could have between two exemplars of the same manufacture a variation in the reading of as much as 1,140 between those two exemplars -- those two known exemplars?
A So far as I can tell, yes. In their processing, it would appear from the numbers that some variation clearly exists. Sometimes you get a moderately big one. And most times they are smaller.
Q Okay. Now, Dr. Guinn, with respect to magnesium, would you please give us the high value that you got on the actual reading on the exemplars and the low values, sir?
A These are on individual samples?
Q Yes, sir.
A Yes. The highest magnesium value was on the number one sample, 2,940 plus or minus 220, and the lowest value that we found was on exemplar number seven which was 1,020 plus or minus 70. Those two had different magnesium concentrations -- quite measurable.
Q Okay. Would it be accurate to say that your actual readings then vary on known portions of the Perry latex glove as much as 920 parts per million -- I am sorry -- 1,920 parts per million, for the known exemplars?
A Yes; that is correct.
Q Let me ask you first, or before we go on to the comparison, what happened with sample number eight of the known exemplar?
A Yes. The sample number eight on the pneumatic tube -- the rapid measurements, the analysis -- the sample wasn't spoiled, but the analysis was spoiled. We shot the thing in and then when it was supposed to come back out, it hung up in the tube and didn't come out. It stayed in there. Instead of having been in the reactor for one minute, it was in the reactor for we don't know just how long, something between one and a half and two minutes. So, we couldn't make an accurate measurement.
Q Did that happen, by the way, on any other samples?
A No. That was the only one, and only on the pneumatic tube. You notice for the other elements, that sample eight -- we did get numbers, because that was from the longer radiation. There was no problem.
Q I guess my question is with regard to sample number eight. Did this similar result occur with respect to any other elements?
A Well, the sample didn't come back. So, that means we couldn't analyze it for magnesium or aluminum or any of the short-lived ones. There was no measurement to be made.
Q Okay. Now, with respect to magnesium sample number one, you got a reading of 2,940; is that correct, sir?
Q Sample number seven -- what was your reading there?
Q In other words, is it possible to say, then, sir, that as between two known samples of Perry brand latex gloves you could have a difference of 1,920 parts per million?
A As extreme values?
Q As extreme values; yes?
A All of the others cluster very closely. You picked the very highest and the very lowest -- the extreme range.
Q Okay, now, if we were to ask you with respect to the evidence samples that you got for magnesium, I believe the chart reflects -- was it 330 parts per million?
Q Okay, and if you were to add 1,920 to that, we would come out with what -- 2,250?
A On what basis would you add 1,920 to that?
Q Well, I'm just wondering -- let's assume hypothetically that were to add a variation --
A (Interposing) No, the most you could add would be whatever the plus or minus is that's shown -- shown here -- or take the highest value which was 380 which had an uncertainty of 270. You could add that to it; 380 plus 270 is 580 -- 650. That's still far short of the lowest of the other values which was 1,020.
Q Well, I don't understand, I guess, why you would go to a statistical value which is smaller than the actual variation between two known samples of Perry brand latex gloves.
A The very lowest value of the exemplars for that particular element -- this is the extreme case -- magnesium -- was 1,020 plus or minus 70 on that particular sample. That means that the true value, whatever that may be, must be pretty close to the 1,020 by only that small margin on that sample. The two of the evidence samples, which I was able to measure for magnesium, had considerably lower values. The uncertainty was somewhat larger because they were smaller samples. I couldn't get the kind of measurement precision. But, even so, they were down around 300 -- both of them, whereas the exemplar samples started at 1,020 and went on up as high as 2,093.
You are trying to establish whether this group of samples is measurably, statistically, significantly different than this group of samples or whether there is no significant difference, and these numbers show a significant difference.
Q Let me ask you: what -- and in your terms, Doctor -- is a significant variation? And let me preface that by saying I believe in direct examination you said something to the effect that if one element appears a hundred times the amount in question as the known, then that is obviously significant.
A No, I was taking an extremely obvious case -- it had nothing to do with these particular data -- no.
Q Well, let me ask you then: what is the low border, if you will, of the significant variation?
A It isn't anything as simple as a ratio like twice, and three times, and so on. It is illustrated by the two diagrams that I showed. If you analyze variants of these samples -- exemplars -- you get a bunch of numbers for one element, and you do the same thing for some evidence samples, and then you put them on paper or graph them like we did here, and you look at this group, and you say, "Do all of these numbers that I get, say, in the exemplar sample -- are they all consistently higher?"
We are then allowing for the measurement of uncertainty. Are they all higher than all these or are they all lower than all these? In other words, as I plot them, if there is a gap in between -- and we could use a set of plus or minus one standard deviation -- if you want to have a higher confidence level, you could use plus or minus two standard deviations, if you want to. If there still is a gap between those distributions, then it means that statistically it is extremely unlikely that they came from the same source.
That's what you would mean. That's a better way to put it.
Q Well, let me ask you this: with respect to the eight known exemplars that you analyzed, did you find any two samples which had exactly the same trace elements in the same concentrations?
A No, no.
Q Would it be accurate to say that, since there were, I believe, three rubber gloves that were used as the exemplars and eight samples were taken, that obviously there must have been more than one sample from each of the gloves; would that be correct?
A I think there was one sample per glove so there were eight gloves -- four pairs as I recall were involved.
Q Four pairs of gloves you say. Okay, well, then, as between these gloves, is it accurate to say that between one glove and another glove in the same package there would be some variation?
A There is bound to be some variation. That is the whole point of it; yes. That is why we made as many measurements as we did.
Q All right, now, let me ask you: with respect to the state of the art in 1971, was it the same, if you know, sir, as it is today?
A Not precisely, but the same kind of equipment that I showed in the slide and which I did use here we purchased in 1970 at the university so it was commercially available at that time.
Q Well, do you know, sir, whether the same equipment and exactly the same methodology and exactly the same time sequence was employed by the ATF examination?
A I don't know. They didn't give any such details in their report. I know that they started doing activation analysis there because I knew the group quite well in the earlier days, and they started work about 1963. So, they had been -- now, in 1963 they didn't have the newer germanium-type detectors, but they came along just a few years later, and I'm quite sure that, even by 1970, they could -- I know in our own laboratory we completely switched over to those and I'm sure they had also.
The only thing that they failed to do was to make the short, rapid measurements which they could do with the same kind of equipment.
Q And you did do those measurements I take it?
Q It's as a result of those measurements that additional trace elements were detected; is that correct?
A Yes. The elements that I determined -- the same ones that they determined in the longer irradiations -- the numbers are somewhat different for perhaps various reasons, but the trends are the same in their results as in mine.
Q Okay, now, with respect to those additional elements that you detected, I believe you testified on direct examination that, with respect to aluminum, sulfur, calcium, and manganese, these were not detected by the ATF in 1971; is that correct, sir?
A There were more than that. The ATF did not detect magnesium, aluminum, sulfur, chlorine, calcium, or manganese, or silver. There were seven that I was able to detect that they did not.
Q Now, of those seven, how many are common to both the exemplars and the questioned samples?
A Well, as I say, just being present -- not saying anything about the magnitude -- all except silver.
Q Okay, now, with respect to silver, in the evidence you found, I believe -- what is it 1.2 parts per million plus or minus 30 percent -- now, would it be accurate to say that if silver is present at all in the evidence, that there is a significantly small amount?
A In what?
Q Is it there in any great amount or proportion?
A Not in great amount, but it is definitely there at about that concentration.
Q So, what we are talking about is the detection or non-detection of somewhere between not quite one part million and 1.2 parts per million?
A Well, in the evidence samples, it was about roughly 1.2 parts per million. In the exemplar samples, I can't say there was nothing there. All I can say is nothing showed up and, if there had been any there, it would show up even at much lower level -- like a tenth of a part per million would have shown up because those were bigger samples which helps in the analysis.
Q Okay, now, with respect to the other elements that I asked you about -- the aluminum, the sulfur, calcium, and manganese -- did I understand you to say that the values overlapped as between the questioned --
A (Interposing) Yes, I think those were -- let me double check it but I think those were the ones where there were differences but there were not large differences between the two groups. Aluminum, sulfur, calcium, and manganese -- there is no great difference between the two groups of samples there. For the other elements, there does seem to be somewhere present rather large differences for certain elements.
Q Okay, but at least with regard to those elements, there are an additional four elements in which the trace evidence is consistent with the ATF finding; is that correct?
A They can't be consistent. They didn't measure them.
Q Well, I was saying it was not -- perhaps it would be more accurate to say and let me rephrase the question: the finding of those additional elements not detected by the ATF in 1970 is not inconsistent with the presence of those elements in the questioned and the known samples.
A Well, I think you are misstating the situation a little bit.
THE COURT: Start over.
THE WITNESS: If you compare two groups --
MR. MURTAGH: (Interposing) I'll strike the question.
THE WITNESS: -- and they are identical almost on I don't care how many elements, if one of them suddenly has ten times as much of some element as the other, they are different. It doesn't make any difference how many similarities you have. If you have one outstanding dissimilarity, they do not have the same origin. That is what I am trying to state.
BY MR. MURTAGH:
Q With respect to those additional elements, did you find any that were ten times --
A (Interposing) Not as many as ten. The largest was magnesium which was six and a half times.
Q Six and a half times -- okay. Now, with respect to the questioned samples, do you know, sir --
A (Interposing) The evidence samples.
Q Yes, the evidence. Do you know, sir, what chemicals, if any, they were subjected to in the course of other laboratory examination?
A I was informed that one of them -- right at the moment I've forgotten which one it was -- was tested with benzidine which is a test for the presence of blood.
Q Were you told, sir, that one of them was tested with ninhydrin?
A I didn't hear that originally, but I heard it later; yes.
Q With respect to the -- what is it -- magnesium which you found, I believe, to be a significantly lesser concentration in the evidence as opposed to the exemplar -- the exemplars were packages of gloves; is that correct, sir?
A Yes; that's where they came from.
Q Right. Would it be fair to assume that since they were packaged, those gloves were not subjected to any wear, so to speak?
A Presumably not.
Q And with respect to the questioned or the evidence samples, what effect, if any, would the exposure to bleach, or paint, or blood, or any household cleanser, or hot water have on the presence of magnesium?
A I think it is unlikely that just hot water would have any effect or -- what was another one that you mentioned there that would not --
A No, there was one other that would not have any effect .
A Well, some things could, of course. Paint might. Oh, yes. You mentioned blood. Blood wouldn't because you can wash it off afterwards. It would not change anything.
Q Okay, what substances, if any, would be responsible or could be responsible for leaching the magnesium, if you understand my question?
A Well, if you put it in acid, for example, you might get material off if it was primarily at the surface; you could leach out some. On the other hand, if you did, that would probably also leach out zinc, and the ratio is the opposite way for zinc. It has four and a half times as much in the evidence samples as the exemplar so that isn't consistent, although I do agree. You can imagine something that you could do with the gloves that would change the composition, I imagine.
Q Would it be possible that the change in composition would occur as a result of household use of those gloves?
A I think that rather unlikely. I mean one doesn't use boiling nitric acid or anything like that in the kitchen, say.
Q How about paint?
A I don't think paint unless it still were on there, but, as I say, I did give these acetone washings which would remove, and they didn't show any obvious evidence of any kind of paint. A bleaching agent possibly. I would have to try an experiment to find out if that did something. But of the things you mentioned, that is about the only one that might I think.
Q By bleaching agents you agree it is possible?
Q Now, if I understand your testimony, Dr. Guinn, you examined the questioned samples, the evidence and the exemplars and, with respect to their texture, did you find them to be the same?
A I did not make any measurements on texture. I just looked at them, and they appeared to be rubber-like materials, et cetera.
Q Would it be accurate to say -- are they latex?
A I couldn't tell without actually making an entirely different kind of analysis. You don't do activation analysis to find out whether it is rubber. You make an infrared spectroscopy measurement which I did not do.
Q Okay, well, I thought I understood you to say --
A (Interposing) I was informed that these, indeed, were -- these exemplars were known latex rubber samples that had been cut from gloves.
Q Well, maybe I misunderstood you. I thought I understood you to say on Direct Examination that you examined the evidence and it was latex?
A I examined samples given to me as latex samples by activation analysis to see what kind of elements were in them.
Q I see. Well, would you agree or disagree that the pieces of rubber could be latex?
A They appear that they could be; yes, sir.
Q Assuming that to be the case, would you agree or disagree that they could have been part of rubber gloves?
A I have really no basis other than what somebody else might tell me, and that would be strictly hearsay. I mean if you look at the things, they are just little pieces. They are of rubber-like material, but other kinds of plastic would be too. So I would not venture a judgment on that unless I were asked at a specific point to go into the laboratory and establish is this piece definitely latex rubber, and, if so, what kind of latex rubber, what polymer. And now, even beyond that, I don't see any way you can say, "Yes, it also came from a rubber glove instead of a rubber something else."
Q Well, if I were to show you a piece shaped like a finger section of the same type of material as you examined, would you have any reason to believe that it is not from a rubber glove?
A The exemplar samples were big enough so that you could see the curvature like in the finger and so on. It did not prove that even the -- to me, it did not prove that it came from a rubber glove, but it was plausible. The other ones were too small to even venture an opinion that way.
Q So, would it be accurate to say that you cannot say that they did not come from a rubber glove?
A No, I can't.
Q Would it be accurate to say that you cannot say they did not come from a surgical-type rubber glove?
Q I believe you testified that in your opinion it would bel I think, highly unlikely that they came from the same manufacturer and the same batch; is that correct?
A Judging on how closely most manufacturers making various kinds of materials try to control their production, you don't find, as a rule, variations by a factor of four, five, or six in some element this way. You do see variations, but they are much smaller.
Q Well, can you say that such a variation could not occur?
A Well, no, anything can happen. I just said before that it was not impossible. It was just very unlikely.
Q Dr. Guinn, can you say positively that these pieces of rubber did not come from a Perry-brand surgical latex glove?
A Could I say positively?
Q Can you say positively?
A 'If you mean by that -- the word "positively" if you mean absolutely --
Q (Interposing) I mean absolutely.
A -- then, I would say "no," I could not say that.
MR. MURTAGH: Thank you. No further questions.
THE COURT: Any Redirect?
MR. SMITH: Just on one area or two, Your Honor, very briefly.
R E D I R E C T E X A M I N A T I O N 3:50 p.m.
BY MR. SMITH:
Q Dr. Guinn, the name "Perry-brand" or "Perry-Pure" latex gloves as has been used by Mr. Murtagh, do you know which was Perry-Pure rubber glove samples -- that is, exemplar or evidence?
A Those were the exemplar samples and were stated to be from that particular -- they came out of the packages and they had that brand name on them; yes.
Q All right, it was stated to you then that the --
A (Interposing) The evidence ones, I, have no idea, obviously, what brand they are.
Q All right, sir. Were you informed as to where in the MacDonald household the Perry-Pure rubber gloves came from?
A I was informed they were found in packages stored somewhere in the kitchen of the house.
Q Were you informed as to where the evidence samples were found in the MacDonald household?
A They were found, I believe, in the master bedroom.
Q So, as far as you knew, you were comparing pieces of material found in the master bedroom with pieces of material found in the kitchen -- all of which came from the MacDonald household; is that correct?
A That is correct.
MR. SMITH: No further questions.
THE COURT: All right, let's take our afternoon recess and come back today at 4:10. Don't talk about the case.
(The proceeding was recessed at 3:51 p.m., to reconvene at 4:10 p.m., this same day.)