Now, when DNA samples such as the swatches, the kind of red swatches you are dealing with in this case, when they are degraded, what does that do in terms of the risk of cross-contamination once they are in a DNA laboratory?
All right. Do you have familiarity with the processes that were used for handling the swatches in this case?
Are you familiar with the testimony of Mr. Fung and Miss Mazzola about how they took the red swatches out of plastic bags and placed them in test-tubes on the evening of June 13th?
All right. Have you--are you familiar with their testimony with respect to the next day taking the blood swatches out of the tubes and scraping them with a pipette, putting them in the white papers that they call bindles, folding them up?
Are you familiar with the testimony of Mr. Yamauchi as to what he did on the morning of June 14th, starting at around 9:00 A.M. through 11:20 A.M. when he processed the reference sample of Mr. Simpson, the Rockingham glove and the Bundy swatches, 47, 48, 49, 50 and 52?
Now, if one were to assume that the Bundy samples, that is, the swatches 47, 48, 49, 50 and 52 were degraded, would that increase the risk of cross-contamination?
Well, assumes facts not in evidence. In your opinion, sir, in terms of the handling of samples in a DNA laboratory, are there problems when one is handling degraded samples with low amounts or no DNA at the same time or period or location when handling samples with high contents of DNA.
Well, I also believe at the very beginning of my testimony I described the fact that if you have something in high concentration next to something in low concentration there is a greater chance that you can get small amounts of material from the substance with high concentration into the one with low, and so there is a greater risk of that kind of cross-contamination because you are handling the two at the same time next to each other.
And the nodding of the jurors indicate that they recollect that from this trial, too, and they recollect it from a month ago.
KEY QUOTENow, are there rules or practices, to your knowledge, in the various protocols for handling samples in forensic labs in other DNA laboratories with respect to handling a reference sample in the same location and in the same period as evidence samples?
And what are those protocols and what is your understanding of those practices? What are the rules?
The rules are that you never handle a reference sample at the same time as any evidence.
KEY QUOTENow, when you say "At the same time," what are we talking about? Are we talking about--could you please describe that.
Well, "Same time" means in the same setting I guess is the way I would describe it, and that doesn't mean that it is in a sequence of events. It means that you don't have--you have a separation in time by a matter of a span of at least, you know, twenty minutes or a half an hour. There is no really exact time period, but the way it is described in these protocols, is that you handle the reference sample, you put it away, you bleach down, you totally clean up, you allow a period of time and then you can handle evidence.
In your experience in reviewing the practices at the Cellmark laboratory, how do they handle reference samples and evidence samples?
Oh, Cellmark, excuse me. Cellmark never handles reference samples and evidence at the same time.
In prior cases when I have inquired of their criminalist, it would be the closest--
All right. Are you familiar with--do you know, according to their protocol--withdrawn. Let's get back to LAPD. Are you familiar with the testimony of Mr. Yamauchi that at about nine o'clock--well, let's take care of all foundation items. Are you familiar with the serology item description notes which are 1185, I have shown them to Mr. Clarke, of Mr. Yamauchi for June 14th and June 15th, his notes of handling the samples?
All right. Are you familiar with his testimony that between the period of 9:00 A.M. and 11:20 A.M. he handled Mr. Simpson's reference sample and created a fitzco card?
He moved next to the Rockingham glove, did a series of pheno tests and cuttings and initialed that glove?
Took samples? And then moved on to do the so-called Bundy blood drop items, 47, 48, 49, 50 and 52? Are you familiar with that?
I believe the order was 52 and then the others, but the exact sequence is different than what you stated, but they were done.
Now, in your judgment was--what is your opinion of this laboratory practice of handling Mr. Simpson's reference tubes in the way Mr. Yamauchi described it and these evidence samples within that period?
Because of the unacceptable risk of contamination from the reference sample which has high levels of DNA and the evidence items that were processed which have low levels.
Now, do you recall that section of Mr. Yamauchi's testimony where he describes that he opened Mr. Simpson's reference sample and blood came out of the tube that went through the chem wipe and onto his glove?
Now, in your experience when you open one of these vacutainer tubes, what happens or what happened?
It is a vacutainer. That means it is under vacuum. It is sort of like opening a coffee can, you can hear it and there is an aerosol that is created.
KEY QUOTEAnd is in--in terms of the DNA content of a reference tube and that aerosol, how does it compare--what is the nature of the DNA content of--of such a substance?
Now, you read Mr. Yamauchi's testimony where you indicated that after he opened the reference tube and the blood went through his chem wipe and went onto his glove that he then disposed of the gloves, he can't recall, either in the evidence processing room or in the serology lab?
All right. Now, given the nature of his testimony about the way he opened the tube, do you think that what he did next in terms of moving onto the analysis of the other sample was an acceptable laboratory practice?
No. I mean, you know, you've had a spillage, you should have basically stopped everything, cleaned down the entire lab and waited for a period of time before you move on to something as critical as evidence items.
All right. Now, the--are you familiar with Dr. Cotton's testimony with respect to the Cellmark and the California association of crime lab directors proficiency study?
And are you familiar with her testimony with respect to how that laboratory got a false positive--false positive errors?
Do you think that that has any particular application to this situation we are talking about here, the way Mr. Yamauchi handled Mr. Simpson's reference samples and these samples on the morning of June 14th?
Are you familiar with the--have you read Dr. Cotton's testimony with respect to the CACLD study?
Have you looked at literature and letters with respect to the results of that study?
All right. Now, what is it about Dr. Cotton's testimony and her description of these events that you think has application here.
Can--is it your understanding that Cellmark made a false positive error even though there were witnesses in the room looking at the transfers?
Now, could you please describe, just in simple practical terms, why you have stated that Mr. Yamauchi's practices between nine o'clock and 11:20 in handling Mr. Simpson's reference sample, the Rockingham glove and the Bundy blood drops, how in practical terms could that cause cross-contamination?
Yes. I mean when you are--you are handling this blood specimen first and it has been admitted that there was a spillage. Now there is blood on the table, there is an aerosol in the air. Now, just as a hypothetical, Mr. Yamauchi has--we have seen his notes. He was obviously writing with a pen. He may have gotten a little blood on that pen, then he walks to the other end of the bench carrying the pen.
Let me put it to you this way: In the process of handling DNA samples are mistakes made in terms of cross-contamination that the analyst does realize?
I call your attention to page 89 of the NRC report and I would like to have this marked as--what is the next in order?
Do you see a--do you agree and would you rely upon the statements at page 89 in formulating your opinions about this case?
--"Laboratory errors happen even in the best laboratories and even when the analyst is certain that every precaution against error was taken."
Now, are you familiar--your Honor, this is a chart entitled 1196, Mr. Yamauchi's diagram of the blood found at Rockingham. Now, Dr. Gerdes--
Dr. Gerdes, are you familiar with Mr. Yamauchi's testimony that after handling Mr. Simpson's reference tube, opening it up, that he--creating the fitzco card, that he moved to the analysis of the Rockingham blood?
And you are familiar with his testimony as to the initialing that he did in the wrist area of the glove?
The sample, the cutting, the pheno testing and the spot checks control that he did on the inside palmar surface and the back side of the glove?
Your Honor, this is Prosecution's 272-A entitled "Rockingham glove results," a series of pictures.
Dr. Gerdes, are you familiar with the results obtained by the Department of Justice using the D1S80 PCR system obtaining results consistent with Mr. Simpson's 24, 25 genotype to a section near the wrist area entitled here G10, a section in the area depicted here as G11--G11 and a section indicated on the inside surface near the notch, G13?
All right. Given the manipulations that Mr. Yamauchi performed on the glove as depicted in his notes and the DNA test results from the amounts of DNA in that D1S80 system, in your opinion could they be the result of sample handling error?
All right. Is it consistent with this DNA result that given the amounts of DNA in the D1S80 system that cross-contamination could have occurred in the areas marked G10, G11 and G13?
Is it a good laboratory practice to have proceeded from handling the reference sample under the circumstances described by Mr. Yamauchi and turn to manipulation of the wrist area of the glove in the fashion that he described?
Incidentally, are the amounts for G10, G11 and G13 on the D1S80 system, the amounts of DNA found in those areas, are those amounts consistent with cross-contamination from small amounts of blood?
Are the amounts of DNA on the D1S80 results there within the nanogram range between two, three, nanogram range as reflected on the DOJ typing results?
The total amount of DNA there is--I don't remember exactly the amount, but the point is that is a mixture, and in a mixture you can't really tell what proportion of the mixture is truly from one contributor or another, although the D1S80 typing result consistent with Mr. Simpson appears to be a minor contributor and that is consistent with the possibility of cross-contamination.
I think I'm going to order that Mr. Harris not leave the courtroom while we are in session, and Mr. Cochran, it is so ordered.
Is it a good laboratory practice to handle in the same period in the same location samples that have high DNA content and low DNA content?
The rules are that you never handle a reference sample at the same time as any evidence.
That is not an acceptable practice in any forensic laboratory.
It is a vacutainer. That means it is under vacuum. It is sort of like opening a coffee can, you can hear it and there is an aerosol that is created.
The D1S80 typing result consistent with Mr. Simpson appears to be a minor contributor and that is consistent with the possibility of cross-contamination.
And the nodding of the jurors indicate that they recollect that from this trial, too, and they recollect it from a month ago.