All right. Good morning, ladies and gentlemen. Dr. Cotton, good morning. Would you resume the witness stand, please.
Robin Cotton, the witness on the stand at the time of the evening adjournment, resumed the stand and testified further as follows:
Good morning again, Dr. Cotton. You are reminded, ma'am, you are still under oath. And Mr. Neufeld, you may continue with your cross-examination.
Thank you. Good morning ladies and gentlemen.
THE JURY: Good morning.
CROSS-EXAMINATION (RESUMED) BY MR. NEUFELD
Dr. Cotton, you may recall late yesterday afternoon I showed you a letter which has been marked as Defense exhibit 1145?
Okay. All right. And having read this five-page letter, the question simply is this: Did you rely on this letter at all when you testified yesterday earlier that there were simply a handful, or I'm sorry, a few members of the scientific community who took issue with the appropriateness of using the assumptions about the independence of inherited genetic traits that you use in forensic DNA typing?
Sustained. Doctor, with regards to this letter, did you consider this letter in any way in forming your opinions that you have given us thus far?
Now, I noticed yesterday Dr. Cotton, that you had your own copy of the national academy of science book "DNA technology in forensic science"; is that right?
Are you familiar with some of the members who are on that committee that authored this book?
And quite simply, is Victor McKusick known as one of the leading geneticists in America?
Would it help if you looked at the biographical information on committee members contained in the back of the book?
That is hearsay, counsel. He is the chairman of the committee. I think that establishes who he is.
And do you know that Paul Ferrara is the director of the Virginia Division of Forensic Science?
And would the same also apply for Dr. McKusick who is the chairman of the committee? Are his opinions those that you would respect?
Despite the fact that he is a very well-known scientist, he may have an opinion on a single issue that I might not agree with and an opinion on another issue that I might, so I can't make a blanket statement that I would agree with every opinion that Dr. McKusick would have.
And would you regard him as an expert in the application of DNA profiling in forensic science?
Would you regard him as an expert in establishing the proper controls and quality assurance for handling items of biological evidence that will subsequently be tested on a DNA level?
And are you aware that he is the director of the Center of Medical Genetics at Johns Hopkins University School of Medicine?
And is it Haig Kazazian's reputation that he is one of the leading members of the genetics community in this country?
And are you aware that she is a Professor of Epidemiology in the School of Public Health at the University of California at Berkeley?
I know that she is interested in population genetics and I have met her on a couple of occasions. I don't know what her overall scientific reputation within her field is.
And would you agree that Dr. Lee is one of the--I'm sorry--are you aware that he is the director of the forensic science laboratories of the Connecticut State Police?
And would you agree that his reputation is of being one of the leading forensic scientists in America?
Finally, are you familiar with this other member of the committee, Dr. George Sensabaugh?
And Dr. Sensabaugh, are you aware that Dr. Sensabaugh is a Professor of Forensic Science and Biomedical Sciences also at the University of California at Berkeley?
And in fact, this member of the committee, Dr. Sensabaugh, has from time to time been a paid consultant to Cellmark, hasn't he?
I don't really--I know that he has consulted with Cellmark back in like 1988. I don't really recall whether he was paid or he just agreed to do that. And he hasn't consulted specifically for us in any way for quite a long time.
And would it be fair to say that you certainly--that he has a very excellent reputation in the forensic science community?
Would you also consider him an expert in the application of DNA profiling to forensic specimens?
Now, to your knowledge, Dr. Cotton, do any of the scientists or forensic scientists who I have named who served on this committee and authored this book, to your knowledge do any of them have a financial interest in any laboratory conducting forensic DNA typing?
Does Cellmark have a financial interest in the outcome of the controversy over the proper methods to estimate the frequency after DNA pattern?
Sustained. Rephrase the question, counsel. Financial compensation is fair game, but the manner in which it is phrased is not appropriate. Rephrase the question.
Cellmark--Cellmark--Cellmark diagnostics laboratory is a business operation, isn't it?
All right. And not only do you charge for the actual testing that you do, for instance, for the Prosecution in this case, but you are paid, for instance, by the Prosecution for your attendance here as an expert witness; isn't that right?
And are those for the days that you are actually on the witness stand or is Cellmark charging $1200 a day when you are simply sitting here in court or upstairs in the District Attorney's office?
Well, if I'm here on business for a particular case, then whatever I'm doing on that business, whether I'm upstairs or down here, is still time away from the lab and so it is still charged at that same rate.
All right. You said that you are the laboratory director for Cellmark in the USA; is that right?
You mentioned at the close of your direct examination, Dr. Cotton, that you furnished the Defense copies of your protocol and databases in this case; is that right?
Now, when you said you furnished copies of your databases as discovery, did you mean that you furnished the actual x-ray films comprising those databases or did you furnish us with computer disks which reflect the sizings of the various people who are in your database?
And in fact, Dr. Cotton, in furnishing such items as the protocols and the databases, you charge the Defense for those items, didn't you?
And would it be fair to say, Dr. Cotton, that for the discovery that we have asked for in this case and received you have charged the Defense more than $5,000?
And that is another way that Cellmark can make money from being retained in a particular case?
Well, for instance, Dr. Cotton, for the various copies of x-ray films of autorads that we have requested in this case as discovery, you charge $25.00 an autorad; is that right?
But for the other autorads that we requested for discovery purposes to assess the quality of your laboratory, you charged $25.00 for each of those?
And do you know, for instance, that the Department of Justice charges $5.00 for each of those x-ray films?
Do you know how much the California Department of Justice DNA laboratory charges the Defense for each autorad that it produces in this case?
Now, when we finished yesterday afternoon, I asked you a few questions about this--this notion of the transfer of technology from medical diagnostics or disease diagnostics to the forensic case. Do you recall that?
And I believe at the end, just to make the transition, your Honor, that you agree that new applications such as forensics may present or pose more problems which may affect the reliability of the new application; is that correct?
Well, I believe what I said was that any new application may pose more problems or less problems than some previous application, so you can't assume, just because it is a new application, that already it has more problems.
All right. Currently, Dr. Cotton, would you agree that there is no federal regulatory scheme requiring that you meet certain minimal quality for your forensic DNA profiling at your laboratory? Would you agree with that fact, with that statement?
There is no federal regulation that regulates the quality of forensic DNA profiling that you generate in your laboratory currently; isn't that correct?
Yes. That would apply to all forensic DNA typing laboratories. There are no federal--specific federal regulations applying to forensic DNA laboratories.
On the other hand, do you know whether, for instance, the national bone marrow program DNA typing procedures are subjected to mandatory federal regulations which govern the quality of their testing?
Okay. Would you agree in fact that currently, Dr. Cotton, there is more federal regulatory control of the quality in testing for strep throat than there is in the quality of testing for forensic DNA profiling?
Now, you mentioned on direct examination that you have been accredited by the American Society of Crime Lab Directors L.A.B.; is that right?
Do you know whether in the field of DNA--DNA's clinical applications in medicine whether accreditation is mandatory by law?
At forensic laboratories that do DNA profiling, is external blood proficiency testing mandatory?
Since there is no regulation, there is nothing to be mandatory. There are guidelines that suggest that that would be a good thing to do, if possible. It is difficult to do--I don't know about other laboratories. We to do some external blind tests, but not very many.
Do you have any knowledge to what extent the Los Angeles Police Department DNA laboratory submits to blind external proficiency testing?
Unlike for forensic DNA laboratories, do you have knowledge whether the laboratories that do the bone marrow typing are subjected to mandatory external blind proficiency testing?
And would you agree that one of the principal purposes of accreditation is to improve the quality of forensic laboratory services?
No, I--that's not why we--I can only speak for why we sought accreditation. I can't speak for why another laboratory would do that.
We wanted to have a clear demonstration and that our laboratory work had been--was meeting the TWGDAM guidelines and other guidelines that were set forth by ASCLAD, and therefore we sought the--we applied and sought the accreditation.
Would you agree that one of the reasons that you wanted to demonstrate that you met the ASCLAD guidelines is to show the public that they can have confidence in the results generated by your laboratory?
And I believe you said that for a laboratory such as your own to get accredited by ASCLAD the laboratory had to be inspected by qualified and independent laboratory managers and scientists?
And I believe you also said on direct examination that whereas you are the first private laboratory doing forensic DNA profiling to be accredited, that there were many others in the sub-sector, namely, local or State University laboratories that were accredited by ASCLAD? Do you recall that?
And to your knowledge understanding, Dr. Cotton, the Los Angeles Police Department is not one of them; isn't that right?
Now, I believe you said, Dr. Cotton, on direct examination, that each laboratory setting out to do DNA profiling must go through its own validation and make sure that its own people can do it well before going on line with case work; is that correct?
Well, would you agree--well, whether or not you said it then, would you agree with that statement?
Would you agree that it is essential that before a laboratory goes on line doing DNA case work that it gain familiarity with the system by using fresh samples?
And would you agree that another thing that a laboratory should do before it goes on line with a particular DNA procedure is to test the marker's survival in dried stains? When I say "The marker," I mean the DNA probes that you are using?
Well, to see how well it does with dried bloodstains, as opposed to fresh blood, for instance?
And would you agree that it is important, as a precondition to going on line, that the forensic laboratory test the system on simulated evidence samples have been exposed to a variety of environmental conditions, such as heat and humidity and sunlight and the rest?
Well, it is important that that be done at some point, but I don't see any reason why every forensic laboratory should have to do that. If that has been done and that work has been published, I see no need for any laboratory to go back and do that same work over and over and over again every time a laboratory is about to come on line with a new test.
All right. Would you agree that it is important that the new laboratory, before it goes on line, test its own system on non-probative evidence samples whose origin is known, simply as a check on reliability?
And finally, Dr. Cotton, would you agree that before a new laboratory goes on line with this technology that it is important that it establish basic--that it establish basic competence in using the system through blind trials?
All right. Mr. Neufeld. All right. Mr. Neufeld, you had just asked Dr. Cotton to explain to the jury what blind trials are.
What I'm going to do is try to explain--use some words so that maybe we are all using the same words. If you get a proficiency test into the lab, generally the laboratory staff is aware that that is a proficiency test. They are not aware of what the answer should be, but they are aware that this is a set of proficiency samples. In answer to Mr. Neufeld's question, if you have a blind proficiency test, that would mean that the laboratory staff would not know that that was a proficiency test sample. That means it has to come submitted as a regular case with a letter of submission, a person of contact, and all the other things that come with a regular case submission, so it has to look like a fake case. And when the laboratory analyst reaches the point where they would call up and say I have enough DNA to proceed or I don't have enough DNA to proceed, there has to be a person who is willing to talk to them and continue to behave as if this is a real case. So finding outside people to assist you in setting up a blind proficiency test is difficult. There are, however, plenty of proficiency test providers for a non-blind test.
So you would disagree with that statement that I just made about the necessity of blind trials before a laboratory goes on line?
Yes. I would agree that laboratories should do a proficiency test before they go on line, but I would not agree that it needs to be a blind proficiency test, because if they are not on line, how can they be accepting a case in the first place, so I don't even see how you would exactly do that.
All right. Dr. Cotton, let me ask you this: Even once they go on line, would you agree that there is no substitute in assessing the quality of the work generated by the laboratory to engage in rigorous external proficiency testing via blind trials on a regular basis?
Dr. Cotton, in arriving at your opinions on this particular matter, did you read the section of the NRC report entitled "Experimental foundation"?
Fine. In arriving at your opinions as to what a laboratory should do as a precondition before using new DNA typing, did you at all rely on that section of the national academy of science's book "DNA technology in forensic science"?
Okay. Now, in your laboratory, I think you mentioned that there are several molecular biologists who process the evidence when it comes in and then analyze the evidence; is that correct?
And do these molecular biologists begin handling the evidence from the moment it arrives or are there other people with less training who do the initial processing of evidence when it comes to the laboratory?
When we talk about unpackaging, we are talking about unpackaging the blood swatches or other types of material that you get from a police department laboratory or wherever?
All right. And I think you mentioned that each of your molecular biologists who begin the processing of the evidence, at least in this case, have six years' experience; is that right?
No. They don't all have six years' of experience. It happens that the two people who worked on this case have six years of experience.
And however, all these molecular biologists who process the evidence from inception--from its arrival, excuse me, are supervised by several ph.D.s; is that right?
They are directly by--they are directly supervised by one of the their own group and then indirectly supervised in terms of the case's review by the Ph.D. staff and they are supervised by myself.
Well, there are four people with a Ph.D. with Cellmark, but three of them are involved in assigning cases.
Do you have any knowledge at all about the extent of the experience of the criminalists who are processing these items of evidence at the Los Angeles Police Department?
Have you had an ongoing relationship with the Los Angeles Police Department's Scientific Investigation Division? "You" meaning Cellmark?
And they have talked to the laboratory director, Michele Kestler, from time to time?
And with respect to your familiarity with the LAPD laboratory, do you know to what extent they have any ph.D.s supervising the work product that comes out of that DNA laboratory?
Now, has Cellmark worked with other laboratories in helping to generate standards for the processing of DNA evidence?
No, we haven't. The group that generates standards or guidelines for the processing--for doing DNA analysis has mainly been TWGDAM and ASCLAD and Cellmark is not a member of the TWGDAM group because we are a business. And up until the point we were accredited we were not a member of the ASCLAD laboratory group or laboratory accreditation group and now we are, but that is very new.
But even if there wasn't a formal relationship between Cellmark and the various forensic laboratories through scientific meetings and other types of informal gatherings, has Cellmark participated in the process and in the dialogue of trying to establish standards with the FBI and other entities for the processing of samples for DNA typing?
We have more participated in the dialogue about scientific issues and we really were not included in the dialogue regarding guidelines for how typing should be done. Nonetheless, the guidelines are--it is apparent they didn't need our input because the guidelines are very good.
Dr. Cotton, you mentioned already that you are familiar with Dr. Henry Lee. Are you familiar--are you familiar with a Dr. Gaensslen?
He is a forensic scientist. I believe he is on the faculty either at Yale or Connecticut and he is also the editor of the journal--the current editor of the "Journal of forensic science."
He is an FBI agent who has been involved in DNA analysis or supervising the--initially supervising the development of the methods that are used at the FBI for DNA analysis.
In fact, wasn't he the Chief of Forensic Science Research and Training at the FBI Center at Quantico?
And have you read the publication by the FBI entitled "Guidelines for the collection and preservation of DNA evidence"?
And you are aware that the authors of this publication by the FBI are Dr. Henry Lee, Dr. Gaensslen and James Kearney from the FBI?
Oh, maybe I need to look at what you are referring to, because what I'm thinking of doesn't have just three authors.
Okay. Thank you. As a person who is the director of a forensic DNA laboratory, are you concerned with issues that involve the preservation and collection of biological samples so they will be able to be tested on a DNA level?
Would you agree that the ability to perform successful DNA analysis on biological evidence recovered from a crime scene depends very much on what kinds of specimens were collected and how they were preserved?
And would you agree, Dr. Cotton, that if the DNA evidence is not properly documented prior to its collection, its origin could be questioned?
Dr. Cotton, you testified on direct examination as to the types of controls utilized by Cellmark in documenting each item of evidence that you process; is that correct?
You have controls to assess how your scientific procedure worked, if that is what you are referring to then.
Well, didn't you also say that there were certain rigorous documentation requirements, such as documenting every transfer of a biological specimen within the laboratory?
There are rigorous documentation requirements. I didn't say that every transfer--and I'm using that term broadly, like we don't write down it is now going to the freezer, you know, stuff like that.
Fine, but if it goes from one package to another package, is that the kind of thing that you have a rigorous requirement that it be documented?
If the sample goes--when it gets transferred from one tube to the next once the processing has started, that transfer--that labeling is witnessed. That is, let me be totally clear. If I were working at the bench, I would hold up a tube with a label that said--would have the case number on it and it would be 02 and I would show my partner the second tube I was going to use which would be empty and it would also have the same case number and 02. I might then turn around and the actual transfer might not be witnessed, but we are concerned that the labeling is correct, so it is the labeling that is witnessed, not the actual necessarily the actual moving of the sample.
Would it be fair to say that the reason you are so concerned and you even have a witness there, is because if the labeling isn't correct, the origin of the ultimate sample that you test may be called into question?
And so would you agree likewise that if the evidence itself is not properly labeled and documented in the same way that you just described it at Cellmark, prior to its receipt at Cellmark, its origin can also be questioned?
Based on your expertise in working with forensic specimens, Dr. Cotton, would you agree that if a sample is not properly packaged cross-contamination might occur?
Well, Dr. Cotton, based on your expertise with forensic specimens, would you agree that if an item of biological evidence is not properly packaged in the first instance when it is collected, that cross-contamination might occur?
Dr. Cotton, based on your experience in handling and processing forensic specimens, are there certain do's and don'ts with respect to the packaging of biological specimens to preserve the DNA integrity?
Overruled. Are there any guidelines that you are aware of, general guidelines, regarding these items?
I'm not aware of any general guidelines. I am aware of how things are commonly done, since I am aware of the types of things that we receive in the laboratory, but I don't have any special expertise in collection of samples, so my knowledge is pretty much limited to what I am aware of that arrives at our laboratory.
But is your knowledge also based on your--your common sense as an experienced forensic scientist? Is that a fair statement?
And that as an experienced forensic scientist used to handling forensic specimens and reading literature on the subject, you have an appreciation of what--what proper controls should be followed when evidence is initially packaged, don't you?
Based on your experience as a forensic scientist, haven't you arrived at certain conclusions and opinions as to what is the proper methods for packaging items of biological evidence at a crime scene in order to preserve it for DNA testing at your laboratory?
I have some basic opinions about what common sense would tell you to do, and beyond that--and I also have some technical information about I know something about--giving you a very brief example, if something is dry, it is better than being stored wet, things like that.
Fine. So I'm only going to ask you questions about what you know about and how it affects DNA, Dr. Cotton. Would you agree that when something is wet one should not package it in a sealed plastic bag?
I wouldn't want to package it in a sealed plastic bag for days. I don't think it would make any difference if it were a short time, but I wouldn't want it to be in there for a long time unless it was cold.
Are you aware of any forensic laboratory protocol that you have ever inspected that authorizes the packaging of wet biological samples in a sealed plastic bag even for a short time?
Dr. Cotton, in your capacity as the laboratory director of a forensic DNA laboratory, have you on occasion inspected the protocols of other forensic DNA laboratories?
I have, but that would only be with regard to the DNA typing procedure protocols. That is, what--how you do the DNA analysis, and I have not inspected or read any other types of protocols from a forensic lab.
Now, Dr. Cotton, in this case a criminalist has testified that she placed wet blood swatches in a clear plastic bag which is folded over so the swatches are less likely to fall out. Would you agree, Dr. Cotton, that by putting a wet swatch into a closed plastic bag that that allows the moisture to remain in the swatch?
If the plastic bag is sealed like a zip-lock, where it is airtight, then that might be a problem. If it is just folded over, it might not be a problem.
Dr. Cotton, if it is folded over such that wet blood in the plastic bag allows the two sides of the plastic bag to adhere to one another, wouldn't that retain moisture?
I don't really know. I haven't seen this plastic bag. I've given you the fullest extent of an answer that I think I can.
Dr. Cotton, while we are getting the plastic bags that are in evidence, based on your common sense and your experience as an expert, would you agree that a small piece of cotton, perhaps four or five millimeters, by four or five millimeters, if it is dabbed in wet blood, would in ordinary circumstances dry within minutes?
Counsel, isn't the issue that we need to address with Dr. Cotton, is the impact of moisture, heat, age on the degradation process of DNA? Isn't that the issue?
Would you agree, Dr. Cotton, that bacteria starts eating up the DNA and the DNA deteriorates and degrade?
Would you agree, Dr. Cotton, that degradation occurs more quickly under the combined effects of moisture and heat?
In your laboratory, Dr. Cotton, where you are the laboratory director, would it be scientifically acceptable to let wet plastic stains remain in sealed plastic bags--
Sorry. Because that is what I have written here. At least I can read correctly, your Honor. I just can't type correctly, I'm sorry.
Dr. Cotton, in your laboratory would it be scientifically acceptable to let swatches of wet bloodstains remain in sealed plastic bags in the rear of a parked truck unrefrigerated and unair-conditioned in the middle of June for up to seven hours?
I don't think that would be my first choice, but please keep in mind that my laboratory doesn't collect evidence and so we don't collect it, we don't have a truck, we just receive it from someone else who has already collected it.
And as a result of that, Dr. Cotton, there is no way that you can control the extent to which the offering agency either degraded those samples or cross-contaminated those samples; isn't that right?
KEY QUOTEDr. Cotton, I will now show you what has already been marked in evidence as Prosecution 163-e, the plastic bags used by Andrea Mazzola to collect the swatches. You notice how when it rests the two sides of the plastic bag actually lay one on top of the other; is that right?
And would you agree, Dr. Cotton, that if based on your experience with biological materials, that if five or six wet swatches were placed on the bottom of that bag, that the plastic would remain in a closed position, namely, the two sides would remain in contact with one another as opposed to in an opposition?
And in a closed position, would you agree, Dr. Cotton, that when in a closed position moisture is retained in the plastic bag, as opposed to having the sample drying?
Counsel, given the size and the regular nature of the bag, I would just suggest we hand one of the bags to juror no. 1, she can pass it through, just one, and we can proceed with the testimony, since it is a small item to look at. Do you agree with that?
All right. Mr. Scheck, would you hand that to juror no. 1, please. Thank you. Proceed.
Dr. Cotton, just so I'm--well, even though the swatch itself doesn't unravel, due to the degradation caused by heat and moisture, invisible changes are occurring; isn't that right?
Well, when you finally remove a swatch from a plastic bag where it has been subjected continuously to heat and moisture, will the swatch still look the same, namely, will it still look as red as it did before it was subjected to the heat and humidity?
Why don't you rephrase that question. I think are assuming facts that aren't in evidence in that hypothetical.
If a swatch was placed in a hot truck in June and it wasn't air-conditioned, for up to seven hours and it remained during those seven hours moist, would the degrading process continue?
Well, just from your own common experience, if an object is left in a black truck which absorbs heat rather than reflecting it--
Hold on. We have an attorney from New York and we have an expert witness from Maryland talking about June weather conditions in Santa Monica. We got a problem here.
KEY QUOTEYour Honor, rather than even getting into that, I think the jury's recollection of how certain criminalists appeared on the videotape will be controlling on this point and I won't even proceed with it.
Would you simply agree, Dr. Cotton, that the warmer it is the more that exacerbates the degrading process?
If there is bacteria present, the warmer it is, that's correct, until it gets too hot, at which point it would kill the bacteria also.
And in fact if there is moisture present that also increases the likelihood of bacteria eating away at the DNA as well, doesn't it?
And if a stain is lying on a sidewalk it would not be unlikely or unreasonable that there would be some bacteria present; isn't that right?
Dr. Cotton, I would like to two show you two photographs which I guess will be next in order.
You may. Counsel, if you are questioning the witness, feel free to approach the witness.
Now, Dr. Cotton, do you remember that I think you said that Dr. Blake was present at the laboratory when certain samples were unpackaged?
And when these samples were unpackaged, Dr. Blake took photographs of them, didn't he?
This is one of the items that was opened when Dr. Blake and Dr. Lee were at the laboratory and it consists of five swatches.
And item 47 are purported to be stains taken from one of the drops at Bundy; isn't that correct?
It is the item number no. 12 that was also opened on that same day and it consists of six swatches.
And is that a fair and accurate representation as to how the swatches appeared that day?
All right. You showed to the witness as to each one of these, 1146 and 1147, a group of three photographs.
Yes, but I'm--since one photograph is simply the external envelope, I didn't feel the need to show that.
All right. Are you offering those as a group of three or just these two photographs?
Now, just--now, you obviously know what the markings are on these different photographs, Dr. Cotton, or you may know, but just from looking at those photographs, for instance, can you tell which swatches came from item 47 and which swatches came from item 12?
And would it be fair to say that as you look at the swatches that purport to be item 47 and purport to be item 12 that you can't tell which ones are very degraded and which ones aren't?
And in fact, Dr. Cotton, I believe you said that--well, let--let the record reflect that the upper photograph represents the swatches from item 47--that purport to be item 47.
And based on your testimony, you would agree that there is a lot more DNA present in the swatches from item 12, which is the bottom photograph, than there is in item 47, represented by the top photograph?
Yes, that is correct. Well, the DNA is in better condition in item 47 than item 12. I haven't compared--I would probably have to go back and think about a comparison for the precise amounts of DNA.
Well, Dr. Cotton, in fact you said one of the ways that you assess the precise amount or approximate the amount is to do a slot-blot, correct?
One of the ways that you determine the quantity of human DNA that is present is through a slot-blot, correct?
Could you check your notes and please tell us what result you obtained for item 12?
Is it me or is it a little warm in here? Apparently our power department here had a power surge, which was what that glitch was. Apparently our air conditioning system went down with that so I'm having Mrs. Robertson check, so if you want to stand up and take your jacket off, be my guest. Let's proceed. I thought it was just me.
I don't know what would give you that idea, your Honor. By the way, may we mark this printout as Defendant's 1148?
And by the way, does that slot-blot represent ten percent of the whole sample or is it again ten percent of the portion that was set aside for PCR testing which is approximately ten percent of the whole sample, or if it is something completely different than both of those, please explain what it represents.
The slot-blot is giving us information about the DNA in the ten percent of the sample that was set aside for PCR testing.
But the portion that you use in the slot-blot, is it ten percent--is it a ten percent solution of that ten percent?
So really then the slot-blot is approximately one percent of the entire sample, approximately; is that right?
Okay. Now, what was the slot-blot reading you got for the amount of human DNA present in item 12?
For the amount that was loaded on the slot-blot, my estimation is this is approximately ..5 nanograms.
And could you please tell the jury what you came up with for the slot-blot on item 47?
Okay. Isn't it a fact, Dr. Cotton, that for item 47, when you ran that slot-blot, the amount of DNA observed was zero?
That doesn't mean that there is none there. It means that this measure can't detect any.
Did you conduct any other test to assess quantitatively the amount of human DNA present in the sample?
Okay. And would you agree that notwithstanding the disparity between the .5 and zero, those differences would not be observed when you look at these swatches before they are tested?
Now, in a hypothetical that Mr. Clarke gave you on direct examination, he talked about the possibility--
He talked about--he asked you to assume that item 47 was a bloodstain found in an area that had soil and leaves in it. Do you recall that?
I do not have the transcript cite, your Honor. That is my recollection. If you want--if you want to take the recess now, I could find that citation during the recess.
All right. Let's do that. All right. Ladies and gentlemen, I'm going to take our morning recess at this time. Please remember all my admonitions to you. Don't discuss the case among yourselves, form any opinions about the case, don't allow anybody to communicate with you, do not conduct any deliberations until the matter has been submitted. And we will see you back in about fifteen minutes. All right. Dr. Cotton, you can step down.
Cellmark is paid for my attendance here. I don't get paid.
would it be scientifically acceptable to let swatches of wet bloodstains remain in sealed plastic bags in the rear of a parked truck unrefrigerated and unair-conditioned in the middle of June for up to seven hours?
Of course. And as a result of that, Dr. Cotton, there is no way that you can control the extent to which the offering agency either degraded those samples or cross-contaminated those samples; isn't that right?
We have an attorney from New York and we have an expert witness from Maryland talking about June weather conditions in Santa Monica. We got a problem here.
May I testify?