Mr. Sims, just to reflect back on where we left off when you were on redirect examination, I had asked you a series of hypotheticals that purported to be based on when evidence was collected in this case, how it was processed for drying. And I believe the last hypothetical left off with the Defendant's reference sample in a plastic bag. Do you recall that?
There was one beyond that. I'm going to object to any repetition of any more of these.
Okay. Let's pick up and I'm going to have to give you some of that information again because it has been quite a while, but let's pick up at that point where the Defendant's reference sample is in a plastic bag. Okay?
Objection. There was another hypothetical beyond that. I will show the Court the record.
Mr. Sims, I want to ask you to assume hypothetically that all the stains from Bundy were seen at midnight, the stains at Rockingham were seen at 6:00 in the morning, that all that evidence from those two locations was collected on June 13th before the Defendant's reference sample was obtained, that all the stains consisted of multiple stain swatches, that all of those items were stored in plastic bags in the same truck. Okay? Are you with me so far?
And I want to just to go back and generally describe the drying preparation, that only one coin envelope was opened at a time.
Each coin envelope had a bindle for the stains and a bindle for the substrate control.
Okay. That those stains and their respective substrate control were put in tubes to dry overnight.
Okay. And that the next morning the box containing those items was taken back down on the table where they were prepared the day before. I'm sorry, if I said alternating between bindle and coin envelopes, we haven't gotten to that yet. There were plastic bags that those swatches and the substrate controls were in initially. Okay?
That the Defendant's reference sample was kept in a plastic bag during this processing period.
That after the stains were dried and put into their respective stain bindles and substrate control bindles the Defendant's reference sample was taken out of the plastic bag.
Okay. That at that point, with all the stains and substrate controls in their bindles in closed coin envelopes, Mr. Yamauchi made a fitzco card. Are you familiar with a fitzco card?
He made that ten to fifteen away--ten to fifteen feet away from where the closed coin envelopes containing the respective bindles were.
Okay. That when Mr. Yamauchi opened the reference tube, the Defendant's reference tube, he had a chem wipe over it.
Mr. Yamauchi then directed his attention to sampling item no. 9, the glove from Rockingham. Okay?
Okay. That then Mr. Yamauchi turned his attention to the coin envelopes that had previously been placed or bindles had been placed into containing the swatches.
That he used the sterile scalpel to make cuttings from the swatches that were contained in either the stain or the substrate control.
That Mr. Yamauchi's sampling consisted, with respect to each of the stains from Bundy, of only cutting a portion of one of multiple stain swatches.
Okay. That I want you to further assume that the balance of the swatches, the ones that he didn't sample, remained in the evidence processing room during the entire subsequent PCR process.
And that each--with each sampling Mr. Yamauchi placed the sampling in a separate microcentrifuge tube?
My objection now is that the hypothetical has gone from assuming something generally to asking him to assume that Mr. Yamauchi in particular did certain things in certain ways.
Okay. That with each sampling Mr. Yamauchi put the sampling in a microcentrifuge tube and capped it immediately.
That he never had more than one microcentrifuge tube opened at a time during this sampling process.
Based on all the information that I have asked you to assume, can you comment on the likelihood that there was any sample to sample cross-contamination if Mr. Yamauchi used those safeguards?
I think it would be extremely unlikely that any cross-contamination would occur and then I think looking at--the key also is to look at any of the results, and if those are negative, then they verify that.
KEY QUOTEOkay. Let's assume--I want you to assume then that all the substrate controls tested negatively and add that to the hypothetical. What would that contribute to your opinion on that subject?
Okay. Now, what is the significance of Mr. Yamauchi never having more than one microcentrifuge tube opened at a time?
Is there any significance--if you accept the hypothetical about Mr. Yamauchi never having one tube opened at a time, what is the significance of that?
Rephrase the question. What is the significance of not having more than one microcentrifuge tube opened at a time during the course of PCR testing?
Yes. By following that procedure that makes it such that one tube is not likely to contaminate the contents of another tube. In other words, if you open a tube and you have another tube opened, then potentially these things we've talked about, such as aerosol, could occur, but by keeping it one tube at a time you are not going to see that problem and you are also less likely to cross-contaminate and mix up samples.
When you say you are not likely, is there any scientific data to support the idea that these amplicons can go through the walls of these tubes?
What is the significance of only working on one coin envelope containing a substrate control bindle and a stain bindle at a time?
Your Honor, at this point asked and answered. He was asked a hypothetical. Now he is going back through each detail of the hypothetical again. And it seems to me that that is cumulative, repetitive and we did it the last time.
Well, the significance of that is that there is less likelihood of any mix-up and also there is less likelihood of any cross-contamination, because if the sample is all closed up, it will not be contaminated by an open sample.
Okay. And the last specific question on this series. What is the significance of--remember I asked you to assume that Mr. Yamauchi only cut a portion of one of multiple swatches that then went off to the PCR process. What is the significance of holding back all those other swatches, particularly if they are sent to other laboratories to do testing?
Well, the significance of that would be that when that part of the examination, that initial part of the examination is done cleanly, then that can also be checked by having other laboratories run those particular remaining samples. What you gather from that is that if one were to make the hypothesis that there was some contamination, one would expect that there would be at best maybe some sporadic contamination. In other words, it is unlikely that all these swatches would all get this bit of contamination. So by having these swatches in reserve, one can check those against the other results.
And I want you to assume, hypothetically, that with respect to Bundy, items 47--these are along the walkway--48, 50 and 52, based on what I have just represented in the hypothetical, that portions of those swatches were processed by Mr. Yamauchi starting in serology, and then in the way they do it, and that the balance of those swatches were sent to your laboratory or Cellmark. Okay?
Let's assume that. What would be the significance of the three laboratories producing the exact same DQ-Alpha typing result? I said three labs; I mean Mr. Yamauchi, LAPD, Cellmark and DOJ.
Okay. Mr. Sims, let's go back to he has cut a portion of the swatch and portions of those--
Counsel, you can ask him the general question about the significance of other labs testing the same samples, but we do have the problem of overlap between the witnesses. Proceed.
Okay. Assume hypothetically that portions were processed by Mr. Yamauchi and by Cellmark and DOJ--
Let's try to get this, Mr. Sims. What is the significance, if samples are sent to different labs, of each laboratory getting the same test result?
Well, again, by having these multiple swatches and by having different laboratories get the same results, that indicates to me that these are in fact valid results, that there is no evidence at all that contamination occurred.
KEY QUOTEOkay. Are you familiar with the concept of handling--or strike that. Are you familiar with the term of handling a sample downstream in terms of processing things in the PCR process?
By processing samples downstream, and I'm working from my left to my right, what I would normally do would be to start with the evidence samples on my left, have those tubes in a rack on my left and then move in this direction of work so that, for example, the reference samples would be--reference samples would be like victim and suspect sample, that sort of sample, those would be downstream in the direction that I'm working, so these would be to my right as I'm working.
Well, the concern would be that if you were to have any sort of cross-contamination you wouldn't want the reference sample to cross-contaminate the evidence. Particularly in a typical case you are worried about the suspect sample cross-contaminating the evidence samples, for example, in a rape case or something like that.
Well, because again this goes to having one tube opened at a time and working in a certain order that that makes it unlikely that any possibility would exist whereby the suspect sample could come back this way into the evidence samples.
Mr. Sims, just to revert back for a second, if Mr. Yamauchi consumed all his samples in testing, okay, assume that, all of his samplings in testing--
Well, one of the advantages of PCR is that you don't have to use up all the sample, if that is what you mean. In other words, you don't--you can get by with using very little material and still get a result and that saves some material, it conserves evidence.
Yes. What you extract you--you consume except for the portion of the extract that you didn't use for the typing, for example.
And just to revert back to my hypothetical, assume that early on cuttings were made and tested and consumed.
Yes. Now I understand what your question is. In other words, those samples, those portions of fabric that have been extracted are no longer useful to us. We would need new portions, unextracted portions of fabric.
Yes. I tested different physical pieces of cloth than the ones that Mr. Yamauchi tested.
Okay. Mr. Sims, we--quite some time ago we saw a Defense exhibit that attempted, through a series of hypotheticals and assumptions that you addressed, to quantify amounts of DNA that was present in 47, 48, 49, 50 and 52. Do you recall that?
And you yourself processed item 117, which was collected from the rear gate at Bundy on July 3rd; is that true?
What is the significance of comparing--to you as a scientist of comparing how much high molecular weight human DNA is left in the Bundy stains to how much DNA is in item 117 that was collected on July 3rd from the rear gate at Bundy?
Well, I don't--I don't think that is a particularly significant comparison because the Bundy samples were clearly--the ones that included 47, 48, 49 and 50, were clearly degraded, so a lot of the human DNA would appear to have been degraded in those samples.
Okay. We will talk details in a few minutes, but is there anything about the comparison of items 47, 48, 49, 50 and 52 with 117 in terms of how much DNA is there that suggests scientifically that item 117 was not on that gate on June 13th?
Is there anything about the comparison or the attempt--I will withdraw that. What, if anything, is there about Mr. Scheck's hypothetical which you were directed to assume numerous things about the amount of DNA, human DNA that was in 47, 48, 49, 50 and 52 when compared with 117, that relates to whether or not 117 was actually on that rear gate on June 13th?
Is there anything about the amounts of DNA that were contained in those items, 47, 48, 49, 50 and 52, when compared with 117, that provides any scientific information about whether or not 117 was on that rear gate on June 13th?
Sustained. You can ask whether or not there is any relationship to their relative age.
Is there anything about the amounts of DNA that were contained in those items that I keep numbering to you that suggests how long any of those items were at Bundy; 49, 47, 48, 50, 52, when compared with 117?
No, again, I don't think it is the amounts of DNA that are significant. I think the significance is probably in the collection, the drying process.
Okay. Let's talk about 115, 116 and 117. You have had a chance to examine and process 115 and 116 as well, have you hot?
Let's take them one at a time. What is there--your observation of the photographs and of 115 and your examination of 115 that might shed some light on how long these things were there?
My understanding is that it is no. 115 that is clearly shown in the photographs from June, and that I used that stain then as a basis to compare it to what I saw in my yields of 115, 116 and 117.
Yes. The way I calculated is I went back and looked at how much DNA I was getting per each weight of the swatch. In other words, remember we talked about weighing these swatches, and so I looked at the nanograms of DNA that I recovered per each milligram of the swatches that were tested, and the--the data that I came up with from that was--and this is for no. 115, 116 and 117--looking at the high molecular weight DNA for a yield gel, no. 115 was 13.5 nanograms per milligram swatch; no. 116 was 13.6 nanograms per one milligram swatch; and no. 117 was about 27 nanograms per one milligram swatch.
So how can you correlate the relative amounts then of those three stains to one another?
Now, in visualizing or seeing the photographs of 115 and 116, what did they look like as they appeared in the photograph that was taken of them that you saw?
Well, if--could I have that particular photo again just to refresh my memory on that.
Now, you have also had an opportunity, through the hypothetical and through reviewing records, to have looked at how much DNA was in item 6 that was over at the Rockingham address, have you not?
And item 52, the stain that was processed for RFLP typing that showed a match with Mr. Simpson by Cellmark?
Okay. And what can you say about the relative amounts of DNA in 6, in 52 and 115 and 116?
Well, it is difficult to compare all of those, but what I did is I looked at no. 6 again with this nanograms of DNA per one milligram swatch because that was a relatively undegraded sample. And I compared that, for example, no. 52 and some of the other Bundy drops as well, and the calculation that I came up with for number 6, which was the Rockingham drop, was about 6.7 nanograms of DNA per one milligram swatch. No. 52 was about 2.4 nanograms DNA per one milligram swatch. And then the other samples, 47, 48, 49 and 50, that ratio was all--all those samples the ratio was less than one so those were the very degraded samples; 47, 48, 49 and 50.
I'm sorry to do this belatedly, but could we write the relative amounts and make that 287 for identification, your Honor?
Now, did you also make a comparison, I think you just alluded to the sample, between the kind of DNA that you saw in item no. 6 from Rockingham and the kind of DNA that you saw in item 48 along the Bundy walkway?
Well, I can tell you that there was what I felt was significantly less DNA in that 48, that Bundy drop, than in the Rockingham drop.
Just by doing this type of comparison and also by looking at the--the yield gel determination to show that there was degradation present in that no. 48 sample, the Bundy drop. This was a degraded sample.
Well, I could see evidence that there was some bacterial growth on it, for example, that this was high molecular weight DNA of non-human origin which suggested to me that it was probably bacterial.
Now, let's throw in another stain, if you will, item no. 12. Are you familiar with Cellmark's processing of item no. 12 from inside Mr. Simpson's residence?
Yes. My understanding is that there was a significant amount of high molecular weight DNA that enabled them to get an RFLP result.
Yes. I believe we did that particular sample very early on in our work-up of this case.
Yes. I would like a moment to check that because this was, I believe, back in August.
Yes, I--this was on page 4 of my notes from August 13. I noted that there was high molecular weight DNA in Cellmark's sample 08 which is LAPD no. 12.
I didn't note any for that sample. I did note some degradation in some of the other samples.
Again, I don't recall seeing that in that particular sample, but I--I just looked for the high molecular weight band. That is all the information I have.
Just generally speaking, I don't want to belabor this point, umm, what is the impact of bacteria when it is--comes in contact with a fresh bloodstain?
Well, the bloodstain provides nutrients for the bacteria to grow so the bacteria basically feeds on that and they thrive at the expense of the bloodstain is what happens.
Okay. In your observations of 115, 116 and 117, when they were processed by you, did you see any signs of bacterial cause degradation?
No. I don't recall seeing any bacterial degradation. The type of pattern I did see with the Bundy drops, I don't recall seeing that with those rear gate samples.
Yes. I would like to review that yield gel just to confirm that. (Witness complies.) Yes, this is--I'm looking at the results on pages 168 and 170 of my notes. I did not see that type of bacterial degradation pattern on those samples that I did see on the Bundy drops that we subjected to a yield gel.
Okay. Assume that item no. 12, the Cellmark RFLP result, that was obtained from inside a residence and there was no apparent presence of bacteria. Would that--would those assumptions be consistent with the kind of results that Cellmark obtained on that sample?
Okay. Assume further that 52, the drop that was obtained from outside in the driveway at Bundy--
--that that is a different surface or substrate than all the ones along the walkway; 47, 48, 49 and 50.
I think that--I don't mind the general inquiry, but I think no foundation for this question.
I'm going to overrule it because, you know, the jury has been out, they have seen the diagram, they know what surface.
Yes. My familiarity is from the scene photographs that I have observed and I noted there are some differences in the substrates.
Well, particularly with the--the drops that my understanding are inside the gate, inside the rear gate, that looked like a somewhat soiled or there was a lot of vegetation around that particular area, whereas 52, my understanding was that was more out by the carport away from vegetation.
What is the significance of that in terms of the observations that you made about the stains that were inside the gate along the walkway?
Well, again, assuming there was less soil in that particular area, for example, or vegetation, those could be the sorts of sources for bacterial growth, so if 52 was away from that type of substrate, it would most likely suffer less than the Bundy inside drops.
Okay. And what about the proximity of the vegetation along the walkway versus distance of the vegetation from where 52 was collected from?
Counsel, I mean haven't we made the point? The jury has been to the crime scene. They know where the vegetation was. They know where the plant growth was. They know how bacteria affects the degradation process.
KEY QUOTESo what effect does this biological material have when we are talking about bacterial-caused degradation of bloodstains?
Well, again that kind of material could provide the bacteria, for example, that would cause this degradation.
Okay. Let's compare the surfaces along the walkway with the painted rear gate where 115, 116 and 117 were removed from. What is the significance of the different kind of surfaces that pertain to these items and bacterial contamination?
Well, again, assuming that those surfaces are away from this type of vegetation and soil, then they would be less likely to be degraded in this process.
Well, again, assuming that it is a fairly clean surface, then that would be less likely to have this soil or vegetation on it than--than something like a walkway near vegetation.
All right. Ladies and gentlemen, we are going to take our recess for the morning session. Please remember all of my admonitions to you. Don't discuss this case among yourselves, don't form any opinions about the case, don't conduct any deliberations until the matter has been submitted to you, don't allow anybody to communicate with you with regard to the case. We will stand in recess until one o'clock. And Mr. Sims, you may step down. You are ordered to return at one o'clock.
I think it would be extremely unlikely that any cross-contamination would occur and then I think looking at--the key also is to look at any of the results, and if those are negative, then they verify that.
By having these multiple swatches and by having different laboratories get the same results, that indicates to me that these are in fact valid results, that there is no evidence at all that contamination occurred.
I did not see that type of bacterial degradation pattern on those samples that I did see on the Bundy drops that we subjected to a yield gel.
Counsel, I mean haven't we made the point? The jury has been to the crime scene. They know where the vegetation was. They know where the plant growth was. They know how bacteria affects the degradation process.