Cross-examination of Dr. Robin Cotton (part 1)

📄 Cross-examination of Dr. Robin Cotton (part 1) — Thursday, May 11, 1995

Address:

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

TRIAL

▲ Day 72 of 167

◀ Jury preparation and exhibits Sidebar: hypothetical questions and cross-contamination ▶

Witness: Dr. Robin Cotton
Examiner: Peter Neufeld
Called by: Prosecution • Date: Thursday, May 11, 1995 • Lines: 66

Peter Neufeld opens his cross-examination of DNA expert Dr. Robin Cotton by challenging the prosecution's characterization that the defense had suggested degradation could change one person's blood into another's. Cotton did not answer his question because George Clarke objected and Judge Ito sustained the objection. Neufeld then constructs a contamination hypothetical: if the Bundy blood drops were not Simpson's and had fully degraded, and if those swatches were brought into contact with Simpson's less-degraded Rockingham samples at the LAPD laboratory, could accidental cross-contamination explain the DNA results? Clarke objects as Neufeld states the accidental-cross-contamination premise, and Judge Ito calls counsel to sidebar before Cotton answers.

# 1 (The following proceedings were held in open court, in the presence of the jury:)

# 2 THE COURT:

All right. Thank you, ladies and gentlemen. Please be seated. Dr. Cotton, would you resume the witness stand, please. All right. Mr. Clarke, as to the items presented thus far, you've completed your direct examination subject to the reopening, correct?

# 3 MR. CLARKE:

Yes, your Honor.

# 4 THE COURT:

Mr. Neufeld, you may commence your cross-examination.

# 5 MR. NEUFELD:

Thank you, your Honor. Good afternoon, ladies and gentlemen.

THE JURY: Good afternoon.

CROSS-EXAMINATION BY MR. NEUFELD

# 6 MR. NEUFELD:

Good afternoon, Dr. Cotton.

# 7 DR. COTTON:

Good afternoon.

# 8 MR. NEUFELD:

Now, Dr. Cotton, on direct examination, you were asked repeatedly during the direct examination whether or not degradation, okay, the process of degradation could change one person's DNA into another, and I believe that each time you answered that question, you said no; is that right?

# 9 DR. COTTON:

That's right.

# 10 MR. NEUFELD:

And by the way, have you been following this trial at all?

# 11 DR. COTTON:

Uh, I've watched, uh, part of the opening arguments and then bits and pieces of testimony and maybe 30 minutes here and there as the trial's gone along.

# 12 MR. NEUFELD:

Okay. Have you at all at any time during these proceedings that you followed, Dr. Cotton, ever heard either Mr. Blasier, Mr. Scheck or myself suggest to any witnesses at all that through the process of degradation, a person's blood could change from one person to another?

KEY QUOTE

# 13 MR. CLARKE:

Objection. Irrelevant.

# 14 THE COURT:

Sustained.

# 15 MR. NEUFELD:

Well, let me ask you a hypothetical, Dr. Cotton. Like you to assume for a moment that the blood drops that were recovered from Bundy do not come from Mr. Simpson, but instead come from some other person, and I would also like you to assume for the purpose of this hypothetical that the blood drops recovered at Rockingham are indeed Mr. Simpson's blood. All right?

# 16 DR. COTTON:

Okay.

# 17 MR. NEUFELD:

Thank you. Now, I would also like you to assume for the purpose of this hypothetical that due to the manner in which the Bundy blood drops were collected, packaged and processed, that they became degraded. Okay?

# 18 DR. COTTON:

Okay.

# 19 MR. NEUFELD:

And, in fact, you've described I think in detail during direct examination how bloodstains or blood drops can become degraded; isn't that right?

# 20 DR. COTTON:

Yes.

# 21 MR. NEUFELD:

For instance, in this case, you mentioned that the--

# 22 THE COURT:

Excuse me, counsel. We're going to have to move this easel because it's blocking two of the jurors' view of Dr. Cotton.

# 23 MR. NEUFELD:

Okay. Sorry.

# 24 (Brief pause.)

# 25 THE COURT:

All right. Thank you, counsel. Proceed.

# 26 MR. NEUFELD:

Sorry.

# 27 MR. NEUFELD:

For instance, you mentioned during direct examination that item 56--and I'm asking that item 56, which is exhibit no. 256, go up on the elmo.

# 28 MR. NEUFELD:

One moment, your Honor.

# 29 (Brief pause.)

# 30 MR. NEUFELD:

And I believe if you would, if you could stand and just use the pointer to point out to the jury where lane 56 is again.

# 31 DR. COTTON:

Down here you mean (Indicating).

# 32 MR. NEUFELD:

Well--

# 33 DR. COTTON:

Yes.

# 34 MR. NEUFELD:

Come over. Come over a little. Now back up one. Blank lanes. There.

# 35 (Brief pause.)

# 36 MR. NEUFELD:

Okay. Is that lane--is that the lane reflecting a DNA test on item 56?

# 37 DR. COTTON:

Yes, it is.

# 38 MR. NEUFELD:

Okay. And as you can see, and I believe as you testified, that lane is clear, right?

# 39 DR. COTTON:

That's right.

# 40 MR. NEUFELD:

And that's an indication that the DNA from that sample degraded considerably; isn't that correct?

# 41 DR. COTTON:

Yes.

# 42 MR. NEUFELD:

And, in fact--

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

# 44 MR. NEUFELD:

And when you first looked at item 56 in the laboratory, before you even looked at it on the level of DNA, you just saw these swatches, you couldn't tell us from just looking at it that the DNA was degraded; isn't that right?

# 45 DR. COTTON:

Of course.

# 46 MR. NEUFELD:

And to the naked eye, in fact, it didn't look any different than item--than item 52 for instance, did it?

# 47 DR. COTTON:

That's right.

# 48 MR. NEUFELD:

Now--

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

# 50 MR. NEUFELD:

Now, I would like you to assume, ma'am--Dr.--excuse me--

# 51 DR. COTTON:

Either way is fine.

# 52 MR. NEUFELD:

Okay. What I would like you to assume, Dr. Cotton, is that those drops on Bundy which did not--which were not left by Mr. Simpson, but were--became degraded in the packaging or handling process such that all the DNA that was in that sample and on those swatches was completely lost to degradation, okay?

KEY QUOTE

# 53 DR. COTTON:

Okay.

# 54 MR. NEUFELD:

Now, what I would like you to assume is that when those swatches from the Bundy drops get back to the Los Angeles Police Department laboratory, they are brought into contact with the swatches from Rockingham, which I've already asked you to assume came from Mr. Simpson, okay?

# 55 DR. COTTON:

Okay.

# 56 MR. NEUFELD:

And that the Rockingham drops or at least some of them, such as item no. 12, were not very degraded, okay?

# 57 DR. COTTON:

That's right.

# 58 MR. NEUFELD:

And I believe you even said on direct examination that item 12 seemed to be in good shape relatively speaking?

# 59 DR. COTTON:

It does.

# 60 MR. NEUFELD:

And--and so there was a lot more DNA in item 12 than there was, for instance, item 52; is that right?

# 61 DR. COTTON:

That's right.

# 62 MR. NEUFELD:

In fact, a lot more DNA on item 12 which comes from Mr. Simpson's foyer than there was on any of the drops from Rockingham; isn't that right?

# 63 DR. COTTON:

That's right.

# 64 MR. NEUFELD:

And what I would like you to assume for the purpose of this hypothetical, Dr. Cotton, is that these blood drops, stains from Bundy, when they're brought back to Los Angeles Police Department laboratory, came into contact with Rockingham drops which had more DNA in it and that those swatches from Rockingham cross-contaminated by accident the swatches from Bundy, okay?

# 65 MR. CLARKE:

I'm sorry, your Honor. Objection.

# 66 THE COURT:

Let me see counsel at sidebar, please, with the reporter.

Temperature

tense

Key Quotes (4)

Peter Neufeld

Have you at all at any time during these proceedings that you followed, Dr. Cotton, ever heard either Mr. Blasier, Mr. Scheck or myself suggest to any witnesses at all that through the process of degradation, a person's blood could change from one person to another?

Neufeld challenges the prosecution's characterization by asking whether Cotton had heard the defense suggest that degradation could change one person's blood into another's; Cotton did not answer because Clarke objected and Ito sustained the objection.

Peter Neufeld

Okay. What I would like you to assume, Dr. Cotton, is that those drops on Bundy which did not--which were not left by Mr. Simpson, but were--became degraded in the packaging or handling process such that all the DNA that was in that sample and on those swatches was completely lost to degradation, okay?

The explicit statement of the contamination theory: Bundy drops weren't Simpson's, they degraded to nothing, then Simpson's DNA from Rockingham cross-contaminated them at the lab.

Dr. Robin Cotton

Either way is fine.

Cotton responds that either form of address is fine after Neufeld hesitates between 'ma'am' and 'Dr.'

Dr. Robin Cotton

That's right.

Cotton confirms counsel's stated comparison that item 12 had a lot more DNA than item 52, a factual comparison used in building the contamination hypothetical.

Evidence (3)

People's 256 (item 56)

Blood swatch from Bundy crime scene; showed a clear/blank lane on gel electrophoresis, indicating severe DNA degradation

displayed on Elmo, discussed to establish that degraded samples look identical to intact ones to the naked eye

Informal

Item 52 — Bundy blood drop, used as comparison to item 56 regarding visual appearance of degraded vs. intact swatches

referenced informally

Informal

Item 12 — blood drop from Simpson's Rockingham foyer, described as 'in good shape' relatively speaking and as having a lot more DNA than item 52

discussed as the contamination source in Neufeld's hypothetical

Notable Exchanges (2)

Peter Neufeld•Dr. Robin Cotton

Neufeld walks Cotton through a multi-step contamination hypothetical — asking her to assume that Bundy drops were not Simpson's, lost all DNA through degradation, and were brought into contact with Rockingham swatches at the LAPD lab. He then poses accidental cross-contamination as another assumption, but Clarke objects before Cotton answers that final premise.

strategic

Peter Neufeld•George Clarke•Lance A. Ito

Clarke objects as Neufeld reaches the payoff question of the contamination hypothetical; Ito calls sidebar. The proceeding ends before Cotton can answer the central question.

procedural

Light Moments (2)

Dr. Robin Cotton

Neufeld fumbles mid-question between 'ma'am' and 'Dr.' when addressing Cotton; she replies 'Either way is fine.'

Lance A. Ito

Ito interrupts mid-question to have the easel moved because it's blocking two jurors' view of the witness.

Credibility Attacks (1)

⚔ LAPD evidence handling (not Cotton directly)

hypothetical framing

Neufeld uses Cotton's expertise to build the contamination theory, eliciting her confirmation that item 56 had degraded considerably and that item 12 was in relatively good shape and contained more DNA than item 52, while presenting contact and cross-contamination of the Bundy and Rockingham swatches as assumptions in his hypothetical.

Witness Demeanor

Calm and cooperative throughout; answers straightforwardly without resistance

Uses the pointer on the Elmo display after Neufeld asks her to stand and point out lane 56

Relaxed enough to joke about 'either way is fine' when Neufeld stumbles over her title

Objections

2 objections (1 sustained, 0 overruled)

Proceeding 6033 • 66 lines • Prosecution witness

Criminal Trial

Department 103