Cross-examination of Gregory Matheson

📄 Cross-examination of Gregory Matheson — Tuesday, December 10, 1996

Address:

C:\DEPT103\CIVIL\1996\DEC\10\CROSS-EXAMINATION-OF-GREGORY-M.DOC

TRIAL

▲ Day 29 of 57

◀ Redirect examination of Gregory Matheson Recross-examination of Gregory Matheson ▶

Witness: Gregory Matheson
Examiner: Robert Blasier
Called by: Plaintiff • Date: Tuesday, December 10, 1996 • Utterances: 36

Defense attorney Blasier cross-examined LAPD criminalist Gregory Matheson on three technical forensic issues: the missing blood volume from OJ Simpson's reference sample (approximately 1.5 cc unaccounted for between collection and toxicology), the expected presence of Nicole Brown Simpson's own DNA under her fingernails, and the limited scientific support for Matheson's claim that a BA blood type can degrade to appear as a B. Matheson acknowledged each point but minimized its significance.

# 1 Q:

When you found -- when a knife was found with the same type of EAP type, that wasn't really pursued by LAPD, was it?

# 2 MR. LAMBERT:

Objection, argumentative, lack of foundation.

# 3 THE COURT:

Sustained.

# 4 Q:

(BY MR. BLASIER) Now, you're aware of how much blood it takes to prepare a Fitzco card, aren't you, it takes 1 cc, correct?

# 5 A:

That's correct.

# 6 Q:

And the card is designed so you -- it takes -- it makes four different sections, each one 250 microliters, I guess?

# 7 A:

That's correct.

# 8 Q:

So you're pretty certain about the fact that when Mr. Yamauchi made his Fitzco card, he took out 1 cc?

# 9 A:

I'd say pretty close to that. I don't know if he specifically used a measuring pipette to do it, but he prepares a lot of those.

# 10 Q:

There's only that one withdrawal between when Thano Peratis collected the blood, and it went to toxicology where they said it had 5.5 cc's?

# 11 A:

That's my understanding.

# 12 Q:

If those numbers are correct, and Thano Peratis withdrew 8 cc's, that would indicate that between the time the blood was drawn and it went to toxicology on June 20, there was approximately one and a half cc's missing, if those numbers are correct?

KEY QUOTE

# 13 A:

If what he drew is correct, that's true.

KEY QUOTE

# 14 Q:

Now, did I understand your testimony about the fingernails is that you said if you don't look closely at the analytical information, that means disregard the test results?

# 15 A:

No, not at all. That's why I don't totally eliminate the possibility of a different type being present. I also understand the limitations of the EAP system and I can take other information into account.

# 16 Q:

Okay.

Now, you would expect to find a person's own DNA under their fingernails, wouldn't you?

# 17 A:

I would.

# 18 Q:

From skin cells or whatever?

# 19 A:

Yes, I would.

# 20 Q:

It's not unusual if you did a DNA test under Nicole Brown Simpson's fingernails, you're going to find cellular material consistent with her, correct?

# 21 A:

I would think so, if they scraped some of it out.

# 22 Q:

Okay.

Now, the EAP test doesn't look at the same part of the blood as the DNA test, correct?

# 23 A:

That's correct. The EAP is on the red blood cells. There's no DNA in the red blood cells.

# 24 Q:

You're talking about comparing PCR with EAP, you're comparing apples and oranges, you're looking at different things, aren't you?

KEY QUOTE

# 25 A:

You're looking at different things. You're not going to necessarily discount that information.

# 26 Q:

You would agree it would be unusual if you didn't find Nicole Brown Simpson's DNA under her fingernails?

# 27 A:

I would expect to see hers along with the mixture, if there was another sample under there.

# 28 Q:

Now, you said you have seen in tests you've performed, a BA degrade to a B, like you found in this case?

# 29 A:

That's correct.

# 30 Q:

How many times?

# 31 A:

Well, I believe I saw it in one other instance in this case, and I can specifically remember a couple other instances. I don't -- beyond that, I'm not sure.

# 32 Q:

You remember testifying at the criminal trial that you had one other situation where you thought you had seen that?

# 33 A:

There was one that I very specifically remember because I testified to it down in Compton Court. I believe I've seen it other times.

# 34 Q:

Are you aware since you testified in the criminal trial, of there being any additional scientific literature that supports at all your position that the B that you saw under the fingernails could have been a degraded BA?

# 35 A:

No, I haven't.

# 36 MR. BLASIER:

That's all I have.

CROSS-EXAMINATION BY MR. LAMBERT:

Temperature

tense

Key Quotes (4)

Examiner (Blasier)

If those numbers are correct, and Thano Peratis withdrew 8 cc's, that would indicate that between the time the blood was drawn and it went to toxicology on June 20, there was approximately one and a half cc's missing, if those numbers are correct?

Central to the defense's planted-blood theory — unaccounted blood volume suggests blood was removed from the reference vial and later planted at crime scenes.

Witness (Matheson)

If what he drew is correct, that's true.

Matheson concedes the math, only hedging on Peratis's original measurement, keeping the planted-blood implication alive.

Examiner (Blasier)

You're talking about comparing PCR with EAP, you're comparing apples and oranges, you're looking at different things, aren't you?

Undermines Matheson's fingernail EAP findings by establishing that EAP and DNA tests measure entirely different biological markers.

Witness (Matheson)

No, I haven't.

Matheson admits no new scientific literature since the criminal trial supports his BA-degrading-to-B theory, weakening his expert interpretation of the fingernail evidence.

Evidence (3)

Informal

Fitzco card prepared by Yamauchi using approximately 1 cc of Simpson's blood reference sample

discussed

Informal

Thano Peratis's blood draw of approximately 8 cc; toxicology recorded 5.5 cc — ~1.5 cc unaccounted for

discussed

Informal

Nicole Brown Simpson fingernail scrapings with EAP and DNA test results

discussed

Notable Exchanges (2)

Blasier•Matheson

Blasier walks Matheson through the blood volume arithmetic — 8cc in, 1cc out for Fitzco, 5.5cc at toxicology — getting Matheson to concede ~1.5cc is missing if Peratis's measurement is accurate.

strategic

Blasier•Matheson

Blasier challenges the BA-to-B degradation theory by asking how many times Matheson had actually seen it, then noting no supporting literature emerged after the criminal trial. Matheson can only recall a handful of instances.

undermining

Credibility Attacks (2)

⚔ Gregory Matheson

prior inconsistent scope / lack of scientific support

Blasier established that since Matheson's criminal trial testimony claiming BA can degrade to B, no additional scientific literature has emerged to support that interpretation, leaving it as a largely unsupported personal opinion.

⚔ Gregory Matheson

concession on apples-and-oranges comparison

Matheson admitted EAP tests and DNA tests measure entirely different biological markers, undermining any attempt to use EAP fingernail results to discount or override DNA findings.

Objections

1 objections (1 sustained, 0 overruled)

Proceeding 8559 • 36 utterances • Plaintiff witness

Civil Trial

Department 103