Cross-examination of Dr. Robin Cotton (part 5)

📄 Cross-examination of Dr. Robin Cotton (part 5) — Thursday, May 11, 1995

Address:

C:\DEPT103\CRIMINAL\1995\MAY\11\CROSS-EXAMINATION-OF-DR-ROBIN-.DOC

TRIAL

▲ Day 72 of 167

Witness: Dr. Robin Cotton
Examiner: Peter Neufeld
Called by: Prosecution • Date: Thursday, May 11, 1995 • Utterances: 74

Peter Neufeld continued cross-examination of Cellmark's Dr. Robin Cotton, focusing on the scientific credentials of defense experts (particularly Nobel laureate Kary Mullis, who invented PCR) and whether the forensic application of DNA technology introduces new reliability challenges. The session ended early at Neufeld's request before he could begin a new subject area.

# 1 MR. NEUFELD:

One second, your Honor.

# 2 (Discussion held off the record between Defense counsel.)

# 3 MR. NEUFELD:

I show you this five-page letter, ask you to take a look at it, please.

# 4 (Witness complies.)

# 5 MR. NEUFELD:

Have you had a chance to look at it?

# 6 DR. COTTON:

Yes, I have.

# 7 MR. NEUFELD:

Thank you. Now, Dr. Cotton, a moment ago, when you said that there were but a few scientists who criticized the assumption of independence, had you taken into consideration this letter?

# 8 DR. COTTON:

No, I had not.

# 9 MR. NEUFELD:

Now that you have--well, have you now considered this letter?

# 10 MR. CLARKE:

Objection. Hearsay. Irrelevant.

# 11 THE COURT:

Overruled.

# 12 DR. COTTON:

I--I would need to reread it. I mean, I didn't carefully read the whole text when you handed it to me just now.

# 13 THE COURT:

All right. Counsel, given the hour, we're not going to do that now. Proceed.

# 14 MR. NEUFELD:

Can I make a copy so the witness can do it overnight?

# 15 THE COURT:

Sure.

# 16 MR. NEUFELD:

Thank you.

# 17 THE COURT:

The issue is, did she consider that in the formation of her opinions and testimony.

# 18 MR. NEUFELD:

Yeah.

# 19 THE COURT:

So proceed. That's just an observation.

# 20 MR. NEUFELD:

Now--okay. You mentioned that Cellmark's system was in part developed by research conducted by Alec Jeffries; is that right?

# 21 DR. COTTON:

Yes.

# 22 MR. NEUFELD:

And I think you even said on direct examination that he--in response to Mr. Clarke's question, that he had been knighted by the Queen in England for his work?

# 23 DR. COTTON:

That's correct.

# 24 MR. NEUFELD:

Well, separate and apart from knighthood, would you agree that the most prestigious award in science is the Nobel Prize?

# 25 DR. COTTON:

Yes, I would.

# 26 MR. NEUFELD:

And are you aware of the fact that Dr. Cary Mullis won the Nobel Prize for Chemistry in 1993?

# 27 DR. COTTON:

Yes, I am.

# 28 MR. NEUFELD:

And are you aware of the fact that he won that Nobel Prize in Chemistry for inventing the PCR process?

# 29 DR. COTTON:

Yes, I am.

# 30 MR. NEUFELD:

And the PCR process that Dr. Cary Mullis invented is the very procedure that you are relying on in your forensic work when you do PCR work; isn't that right?

# 31 DR. COTTON:

That's correct.

# 32 MR. NEUFELD:

And are you aware that Dr. Cary Mullis is a Defense --

# 33 MR. CLARKE:

Excuse me. I'm sorry. Objection. Hearsay.

# 34 THE COURT:

I didn't hear the full question. Are you aware that he is one of the--he is what?

# 35 MR. NEUFELD:

One moment.

# 36 (Discussion held off the record between Defense counsel.)

# 37 MR. NEUFELD:

Are you aware that Dr. Cary Mullis, who won the Nobel Prize for his discovery of PCR, is one of the Defense experts in this case?

# 38 MR. CLARKE:

Objection. Assumes facts not in evidence. Irrelevant.

# 39 THE COURT:

Overruled.

# 40 DR. COTTON:

I've been told that, yes.

KEY QUOTE

# 41 MR. NEUFELD:

Now, also on direct examination, Dr. Cotton, you said that many of the techniques that are utilized in forensics have been used in other fields as well; is that right?

# 42 DR. COTTON:

Yes.

# 43 MR. NEUFELD:

And I believe that one of the fields that you referred to was clinical medicine; is that right?

# 44 DR. COTTON:

Well, I probably said medical diagnostics.

# 45 MR. NEUFELD:

Okay. Well, I actually think that--

# 46 DR. COTTON:

It's the same term. It's fine.

# 47 MR. NEUFELD:

Okay. One of the examples you gave I believe was that it's used in bone marrow and organ transplant laboratories?

# 48 DR. COTTON:

Are you talking about DNA testing in general or PCR?

# 49 MR. NEUFELD:

PCR testing.

# 50 DR. COTTON:

It could be used. I don't know if it's being used or not specifically.

# 51 MR. NEUFELD:

Well, do you know whether or not--in fact--I'm sorry. The DQ-Alpha test that you do, is that part of a cluster of markers known as HLA?

# 52 DR. COTTON:

Yes, it is.

# 53 MR. NEUFELD:

And is, to your knowledge, the HLA system also utilized by the laboratories that do bone marrow transplants?

# 54 DR. COTTON:

This specific test for this specific marker or HLA in general?

# 55 MR. NEUFELD:

That HLA or the HLA cluster is utilized by--by bone marrow transplant laboratories so they can look for donors, possible donors, type them using DNA typing and then match them with somebody who is in need of a bone marrow transfer?

# 56 DR. COTTON:

I don't think that most tissue typing, that is looking for matches for transplants, is done by DNA. I didn't mean to specifically use that example. When I--when I referred to bone marrow transplanting, I was referring to following the results of the transplant after it occurred, and DNA RFLP analysis I know is used for that purpose because we have done some of that in our laboratory, and there may be other laboratories that have done that as well.

# 57 MR. NEUFELD:

Now, you said that--well, that in the forensic context, what you've done is, you've taken this existing technology and you've transferred it to the forensic application. Is that a fair statement?

# 58 DR. COTTON:

Yes.

# 59 MR. NEUFELD:

And would you agree that when you transfer an existing technology to a new application, there can be significant differences in its implementation?

# 60 DR. COTTON:

Well, sure.

# 61 MR. CLARKE:

Excuse me. Objection. I'll withdraw the objection.

# 62 MR. NEUFELD:

And would you agree that sometimes the new application can be more difficult and challenging than the original application?

# 63 MR. CLARKE:

Objection. Vague.

# 64 THE COURT:

I'll allow it to stand.

# 65 DR. COTTON:

I'm sure that could be the case.

# 66 MR. NEUFELD:

And that the new application may present more problems of interpretation which may affect the reliability of the new application?

# 67 DR. COTTON:

It may present more problems or it could present less problems.

KEY QUOTE

# 68 MR. NEUFELD:

Now--

# 69 MR. NEUFELD:

I need the exhibit.

# 70 (Brief pause.)

# 71 MR. NEUFELD:

Your Honor, I'm going to go into a new subject, which is going to take a while. Could we stop now?

# 72 THE COURT:

Sure.

# 73 MR. NEUFELD:

Okay. Thank you.

# 74 THE COURT:

All right. Ladies and gentlemen--Dr. Cotton, you can step down. Ladies and gentlemen, we're going to take our recess as far as the jury is concerned at this time. Please remember all of my admonitions to you; don't discuss this case amongst 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. And we'll stand in recess as far as the jury is concerned until 9:00 o'clock tomorrow morning. And, Dr. Cotton, you are ordered to return tomorrow morning 8:45. All right. All right. Let's clear the jury, then we'll go on to the other motion.

Temperature

tense

Key Quotes (3)

Dr. Robin Cotton

No, I had not.

Cotton admits she had not considered a five-page letter (apparently signed by multiple scientists criticizing the independence assumption) when she testified that only 'a few scientists' criticized that assumption — a significant impeachment of her direct testimony.

Dr. Robin Cotton

I've been told that, yes.

Cotton confirms awareness that Nobel Prize-winning PCR inventor Kary Mullis is a defense expert, setting up a credibility contrast with prosecution-aligned experts.

Dr. Robin Cotton

It may present more problems or it could present less problems.

Cotton resists conceding that forensic application of DNA technology is inherently more difficult or less reliable than clinical applications, a key defense theme.

Evidence (1)

Informal

Five-page letter, apparently signed by scientists criticizing the assumption of independence in DNA population statistics

shown to witness to impeach her claim that only 'a few scientists' criticized the assumption

Notable Exchanges (3)

Peter Neufeld•Dr. Robin Cotton

Neufeld impeaches Cotton by showing her a multi-scientist letter criticizing the independence assumption, which she had not considered when testifying that critics were few in number.

strategic

Peter Neufeld•Dr. Robin Cotton

Neufeld establishes that PCR — the very technique Cotton relies on — was invented by Kary Mullis, a Nobel laureate who is also a defense expert in the case.

strategic

Peter Neufeld•Dr. Robin Cotton

Neufeld presses Cotton on whether bone marrow transplant labs actually use PCR/HLA DNA typing; Cotton walks back her own direct testimony example, clarifying she meant post-transplant monitoring, not donor matching.

revealing

Credibility Attacks (3)

⚔ Dr. Robin Cotton

prior inconsistent statement / omission

Neufeld showed Cotton a five-page letter from scientists criticizing the independence assumption in DNA statistics; she admitted she had not considered it when she claimed only 'a few scientists' held that view.

⚔ Dr. Robin Cotton

impeachment by authority

Neufeld highlighted that Kary Mullis — Nobel Prize winner for inventing PCR, the very technique Cotton relies on — is a defense expert, implicitly contrasting institutional credibility.

⚔ Dr. Robin Cotton

prior inconsistent statement

Cotton retreated from her own direct-examination example about bone marrow transplant labs using PCR, clarifying she meant post-transplant monitoring rather than donor typing — narrowing the analogy she had used to bolster forensic DNA reliability.

Objections

6 objections (0 sustained, 2 overruled)

Proceeding 6023 • 74 utterances • Prosecution witness

Criminal Trial

Department 103