📄 Cross-examination of Dr. Fredric Rieders (part 4) — Monday, August 14, 1995
Address:
C:\DEPT103\CRIMINAL\1995\AUG\14\CROSS-EXAMINATION-OF-DR-FREDRI.DOC
TRIAL
▲ Day 135 of 167

Cross-examination of Dr. Fredric Rieders (part 4)

Witness: Dr. Fredric Rieders
Examiner: Marcia Clark
Called by: Defense • Date: Monday, August 14, 1995 • Utterances: 138
Marcia Clark cross-examines defense toxicology expert Dr. Fredric Rieders about his opinion that EDTA found on the sock and gate stains came from preserved blood. Clark focuses on undermining his scientific methodology — specifically the distinction between 'detecting' and 'identifying' a compound in mass spectrometry, and whether his standard of a single parent and single daughter ion is sufficient for identification. She also probes whether he changed his opinion after learning of FBI Agent Martz's unpreserved blood test results, which showed similar EDTA levels.
1 MS. CLARK:

And didn't you agree, when I cross-examined you last you were here in July on this, that the results on Agent Martz' unpreserved blood were very similar to that of the gate and the sock?

2 DR. RIEDERS:

I think I said the results that he obtained and from the unpreserved blood. Whether it was in fact unpreserved blood, I have no way of knowing.

3 MS. CLARK:

When I asked you, sir, whether or not you thought he was lying about that, you said no, you had no reason to doubt that he was being honest in testing his own unpreserved blood. Do you recall that?

4 DR. RIEDERS:

I don't recall it, but I would agree with it. I don't think he is lying. I think he is mistaken in one way or another.

5 MS. CLARK:

Well, sir, so after you wrote your July 17th report, which you agree shows the single parent and single daughter ion for both the gate and the sock stain, you learned of the result of Agent Martz' own unpreserved blood test, and after that you came in to testify on July 24th, correct?

6 DR. RIEDERS:

Yeah.

7 MS. CLARK:

And then when you took the witness stand on July 24th you had filed no addendum changing your findings that were indicated in the report, correct?

8 MR. BLASIER:

Objection, asked and answered.

9 THE COURT:

Sustained.

10 MS. CLARK:

And when you testified at that point only you told this jury that you found the full daughter spectrum on the sock taken; isn't that correct?

11 DR. RIEDERS:

I didn't find it. I saw it, the full daughter spectrum, yes.

12 MS. CLARK:

You testified to your opinion that you saw the full daughter spectrum on those graphs on July 24th, correct?

13 DR. RIEDERS:

No, no. Wait. I saw the full daughter spectrum. It was presented to me. On it I pointed out that you could really see all three, even though poorly, but you could see it.

14 MS. CLARK:

That is your opinion, correct, Dr. Rieders?

15 DR. RIEDERS:

I pointed it out. Obviously it is my opinion. But I also left it for anyone else to form their opinion.

16 MS. CLARK:

And Dr. Rieders, between the time that you--you testified that you found--you testified that in your interpretation and your opinion the full daughter spectrum was found on the sock on July 24th, correct?

17 DR. RIEDERS:

I think--was it the sock?

18 MS. CLARK:

Yes.

19 DR. RIEDERS:

It was one of them. That is all I know, yeah.

20 MS. CLARK:

But your report does not reveal that you found the full daughter spectrum on the sock which was written on July 17th, correct?

21 MR. BLASIER:

Objection, asked and answered.

22 THE COURT:

Overruled.

23 DR. RIEDERS:

No, I did not.

24 MS. CLARK:

What testing, if any, did you conduct between July 17th and your testimony on July 24th?

25 DR. RIEDERS:

I didn't conduct any testing at any time, as I have repeatedly told you.

26 MS. CLARK:

And other than--did you review the graphs again between July 17th and July 24th?

27 DR. RIEDERS:

Not as much in detail as I had before. I was asked things about some of them. I reviewed that. That is it.

28 MS. CLARK:

Isn't it true, sir, that in order to overcome the very similar findings in Agent Martz' unpreserved blood to that of the gate and the sock stain, you decided to change your opinion concerning your interpretation of the graphs on the sock stain so that you could say that it was from preserved blood; isn't that correct?

KEY QUOTE
29 DR. RIEDERS:

No, that is absolutely misleading and incorrect.

KEY QUOTE
30 MS. CLARK:

Well, sir, let me ask you this: Is there a difference in science between the term "Detected" and "Identified"?

31 DR. RIEDERS:

Sure there is.

32 MS. CLARK:

When you detect something, that means that it may be consistent with a compound, but isn't necessarily that particular compound that you are trying to--you are trying to look for?

33 DR. RIEDERS:

Not necessarily. Detection can be so strong that it is at the same time a positive identification. Ordinarily in the forensic toxicologic sequence of analysis where the--what we call in forensic toxicology an acceptable--forensically acceptable quantum of proof, you do two physical chemically independent tests. The first one preferably is one that is particularly sensitive, even at the sacrifice of specificity, and you call that a detection test, and then do you a second independent one which is a corroboration or negation test, and so between the two, you have an identification as a basic requirement.

34 MS. CLARK:

Then to boil it down, sir, if you have detection, you may or may not have the compound. If you have identification, you in fact have the compound?

35 DR. RIEDERS:

You may or may not. You can't ever be sure. You go to the point of reasonable scientific certainty with the tools that you have and what you have available.

36 MS. CLARK:

And would you agree that there is a distinction, sir, between something that is presumptive for a certain compounds and something that is identified as a certain compound? Is there a higher degree of certainty with respect to a compound that is identified than a compound that is determined to be presumptive for?

37 MR. BLASIER:

Objection to the use of the term "Presumptive." It is a legal term.

38 THE COURT:

Overruled.

39 DR. RIEDERS:

Presumptive can be as strong as identified. Any analysis that you do for a compound, if you get a result that fails to disprove its presence, is presumptively positive. If you have several different types of tests, all of them fail to rule it out by showing it could be there, then together between them we call this reasonable certainty of identification. That is how we work that. That is the mental algorithm that is standard in this community. That means you don't prove anything. You fail to disprove; that is what you do.

40 MS. CLARK:

Then do you not agree that there is a distinction between the terms "Detected" and "Identified"? Is that your testimony?

41 MR. BLASIER:

Objection, misstates his testimony.

42 THE COURT:

Overruled.

43 DR. RIEDERS:

There is an obvious difference. They are two different words and they require, in any particular case, definition.

44 MS. CLARK:

Then Dr. Rieders, would you agree that "Identify" implies a higher degree of scientific certainty than "Detected"?

45 DR. RIEDERS:

A higher degree of scientific certainty for identification, yes, but not for presence or absence.

46 MS. CLARK:

Yes, doctor, and presence or absence means it may or may not be there, correct?

47 DR. RIEDERS:

Well, that--

48 MS. CLARK:

It may be there, but it may not, and when you said "Identified," it is a higher degree of scientific certainty; isn't that true?

49 DR. RIEDERS:

It still may be the compound or it may be something else. It can always be different. You have failed to disprove its presence. Every time you fail to disprove, you add another quantum to having identified it. You fail to disprove. You run a series of tests. If these tests are all positive, you have failed to rule out that compound. At one point or another you say I have done enough tests. I'm reasonably sure that is what it is, taking everything else into consideration.

50 MS. CLARK:

All right. Doctor, would you say--let me ask you a different question. There are such things as presumptive tests, correct?

51 DR. RIEDERS:

Any single test is no more than a presumptive test.

52 MS. CLARK:

Well, then do you see any distinction between a test that is a presumptive test and a test that is confirmatory test?

53 DR. RIEDERS:

Yeah. Confirmatory is done after the presumptive.

54 MS. CLARK:

All right. So when something is done on a presumptive test and comes up positive, you say you have a result that is presumptive for "X," whatever you are looking for, correct?

55 DR. RIEDERS:

Right.

56 MS. CLARK:

Then when you go on and do further testing, you will confirm the presence or rule it out, correct?

57 DR. RIEDERS:

Confirm it or negate it with the next test. If do you a third test, do you again the same process. It confirms the previous one or it negates the previous results.

58 MS. CLARK:

And wouldn't you agree, doctor, that in mass spectrometry you can only confirm a compound if you have the full daughter spectrum?

59 DR. RIEDERS:

Absolutely not. That is nonsense. Whoever gave that you idea?

KEY QUOTE
60 MS. CLARK:

If people who were expert in the use of the tamdem mass spectrometer said that that is what you had to do, would you disagree with them?

61 DR. RIEDERS:

No, that is what they have to do. That is their opinion, but it isn't--as I said before, it is not etched in concrete. It is not from Olympus.

62 MS. CLARK:

All right. So it is your--

63 DR. RIEDERS:

A lot of identifications in forensic science in ms/ms are done on the basis of the parent ion and the single daughter ion. It is done everyday with people who that have instrumentation.

64 MS. CLARK:

Then your opinion, Dr. Rieders, is that you are entitled to create your own standard for when something should be identified or not? Is that your testimony?

65 DR. RIEDERS:

No.

66 MR. BLASIER:

Objection.

67 THE COURT:

Sustained.

68 MS. CLARK:

Is it your testimony, sir, that you feel that you can make an identification based on your own criteria?

69 DR. RIEDERS:

If they are only my own criteria, then they are junk science. If they are criteria which are shared by my colleagues, then I can say yes. You know, if they have stood the test of time and of cases.

KEY QUOTE
70 MS. CLARK:

But then it is your opinion, doctor, that you set your own standard and you determine whether or not a certain standard is correct or not?

71 DR. RIEDERS:

No, I don't set the standard.

72 MS. CLARK:

If others disagree with the standards you have set, do you change your opinion?

73 DR. RIEDERS:

Just because they have a different opinion? No. One debates it and when comes a point where there is proof that one is right, the other is wrong, then you change your mind.

74 MS. CLARK:

But you decide when that happens; isn't that correct?

75 MR. BLASIER:

Objection, argumentative.

76 THE COURT:

Overruled.

77 DR. RIEDERS:

Either I or the scientific community decides. Up until the point that there is a consensus, if people have my opinion, share my opinion, then we are a group that have one opinion; somebody else has another opinion. Doesn't mean that either one is right. Eventually is turns out that one or another one is right or perhaps both are.

78 MS. CLARK:

With whom did you consult to determine that your standard of a single parent and single daughter ion is sufficient to say that you have identified the presence of a certain compound in a mass spectrometer?

79 DR. RIEDERS:

I looked in the literature, no. 1, on ms/ms work. I have over the years many times, because we have been considering getting into it.

80 MS. CLARK:

What literature is that, doctor?

81 DR. RIEDERS:

Hum?

82 MS. CLARK:

What literature?

83 DR. RIEDERS:

Scientific literature, technical literature from the ones that I looked at from Finnegan who makes the TSQ instrument that I think Dr. Martz used, then Hewlett Packard who has put out that kind of an instrument, ms/ms instrument.

84 MS. CLARK:

And do those articles indicate that it is appropriate to identify the presence of a compound as opposed to just detect it on the presence of a single parent and single daughter ion? Is that what they say?

85 DR. RIEDERS:

In some cases, yes, it is.

86 MS. CLARK:

Could you produce those articles for us, sir?

87 DR. RIEDERS:

Oh, I suppose I could if I went back and called them up to send me copies of them.

88 MS. CLARK:

Could you please use the microphone, Dr. Rieders. The court reporter is having a hard time.

89 DR. RIEDERS:

I'm sorry.

90 MS. CLARK:

If somebody in the scientific community disagreed and felt that your--that the standard you've enunciated for us of a single parent and single daughter ion for the purpose of identifying a compound was inappropriate and too lax, you would simply disagree with them. Is that your testimony?

91 DR. RIEDERS:

Yes, I would. I mean, they are entitled to their opinion, but it is not mine. We have no proof of that.

92 MS. CLARK:

All right. Now, you indicated that there is a difference between presumptive and confirmed, correct?

93 DR. RIEDERS:

It is a semantic difference, yes, but it is an important difference, but it is semantic. It refers to the first test which no matter what it is, it is the first test. The second physical chemically independent test then corroborates or negates, so it becomes the confirming or negating test.

94 MS. CLARK:

Let me show you the last page of your report. Now, directing your attention, sir, to the last paragraph which is labeled B, where you indicate: "Thus the finding of EDTA in a micro blood specimen, such as in the present ones, is consistent with, indicative of and presumptive for the blood having originated from a specimen which has been placed into a usually lavender top blood collection tube such as is commonly used to draw blood from a living person and keep it from coagulating." And the terminology you use in that paragraph, sir, is "Consistent with, indicative of and presumptive for"; isn't that correct?

95 DR. RIEDERS:

That's correct.

96 MS. CLARK:

And in none of those words do you indicate the final or confirmatory language such as "Identify"; isn't that right?

97 DR. RIEDERS:

Well, in this case it is not a question of identified. When you talk about--well, yeah, I guess so. It doesn't say identify that that was it, that it was EDTA blood from the tube, because you can't say that. You can only say this is EDTA blood. Presumably because the most common source for it is a lavender-topped tube. It came from a lavender topped tube, but it doesn't mean it did in fact come in that; it could come from other sources. I don't know where it came from, in short.

98 MS. CLARK:

And the other sources it may come from, sir--well, let me ask you this: Are you aware that there are four different types of EDTA?

99 DR. RIEDERS:

There are many more than four.

100 MS. CLARK:

But at least four?

101 DR. RIEDERS:

There are more than four, so there are four, but there are also much more than four.

102 MS. CLARK:

This one is calcium disodium; isn't that right?

103 DR. RIEDERS:

That is one of them.

104 MS. CLARK:

And that is used for a food preservative?

105 DR. RIEDERS:

Calcium disodium EDTA is used for a lot of things, included treating lead poisons.

106 MS. CLARK:

As well as a food preservative?

107 DR. RIEDERS:

It is not a preservative in that it ties up metal and keeps the color of food. In fact, it doesn't keep it from rotting.

108 MS. CLARK:

Are you aware that it is also used as a food preservative? Did you know that?

109 DR. RIEDERS:

It doesn't work as a preservative. Preservative means prevents bacterial degeneration. It doesn't do that the. It is not an anti-bacterial compound.

110 MS. CLARK:

If I were to show you, sir, an article--excuse me. A page out of the Merck index indicating that calcium disodium was in fact used as a food preservative along with the purpose of treating lead poisoning, would you change your opinion, sir?

111 DR. RIEDERS:

Of course not. It is a preservative of color and flavor, but not of food as edible food. The food preservative is something which keeps food edible and this won't do it. It will be bacterially degraded just as if you didn't have it in there.

112 MS. CLARK:

All right. Then it is your testimony that although it may not preserve food, it is a color retentive product?

113 DR. RIEDERS:

In some cases.

114 MS. CLARK:

For food?

115 DR. RIEDERS:

Look, what it does is it ties up the metals that oxidize color and flavor. It inactivates them. That is its purpose in food.

116 MS. CLARK:

All right. Then it is used in food, though, is it not?

117 DR. RIEDERS:

Yes, it is. Sure.

118 MS. CLARK:

All right. Then there is disodium only, correct?

119 DR. RIEDERS:

Hum?

120 MS. CLARK:

I'm talking about the types of EDTA. There is also disodium, straight disodium?

121 DR. RIEDERS:

Disodium EDTA is another one that is disodium dihydrogen EDTA which when you put it into food it usually very quickly goes to calcium or depending on what--mostly calcium.

122 MS. CLARK:

All right. And then there is sodium EDTA, correct?

123 DR. RIEDERS:

Yeah.

124 MS. CLARK:

And there is trisodium EDTA?

125 DR. RIEDERS:

Yup. There are many others, as I said.

126 MS. CLARK:

Now, the way the anticoagulant works is that it binds up the calcium in your blood which is the clotting agent; is that right?

127 DR. RIEDERS:

That is the anticoagulant effect, yes.

128 MS. CLARK:

We have just gone through four of the forms of EDTA. Do you know which of those can be used as a food preservative, sir?

129 DR. RIEDERS:

You could use any one of them because the purpose of it is to tie up iron, copper and a few other heavy metals which cause changes in color and changes in flavor, so you can use any one of them, from a technical point of view, provided the acidity or basidity of the food is properly adjusted. The trouble is that the free EDTA isn't water soluble; the sodium EDTA is.

130 MS. CLARK:

Now, do you know whether these forms of EDTA were ever tested for the purpose of determining what the maximum tolerance would be in a normal healthy person?

131 DR. RIEDERS:

You mean in food? Is that it? When you say maximum tolerance, how? Intravenous or in food or what? Vast difference.

132 MS. CLARK:

No, sir. I asked you whether there was any testing that you know of that determined whether any of the forms of EDTA that we have just talked about, those four--

133 DR. RIEDERS:

Right.

134 MS. CLARK:

--was ever done to see what the normal level would be in an average healthy person?

135 DR. RIEDERS:

Yes. The study of Foreman and Trujillo dealt with normal healthy persons.

136 MS. CLARK:

Objection, nonresponsive.

137 THE COURT:

Overruled, overruled.

138 DR. RIEDERS:

And in this they determined what the level in their blood was, which was in the low parts per billion below their detection levels.

Temperature

tense

Key Quotes (5)

Dr. Fredric Rieders
Absolutely not. That is nonsense. Whoever gave that you idea?
Rieders dismisses Clark's assertion that a full daughter spectrum is required for identification in mass spectrometry — a sharp, unambiguous rejection that reveals the core scientific dispute.
Dr. Fredric Rieders
If they are only my own criteria, then they are junk science. If they are criteria which are shared by my colleagues, then I can say yes.
Rieders defines his own standard of validity, inadvertently giving Clark an opening to argue he's operating in isolation from mainstream forensic science.
Dr. Fredric Rieders
You don't prove anything. You fail to disprove; that is what you do.
Rieders articulates the philosophical basis of forensic science, but the phrasing — repeated throughout — sounds equivocal and gave Clark material to suggest his conclusions lack certainty.
Marcia Clark
Isn't it true, sir, that in order to overcome the very similar findings in Agent Martz' unpreserved blood to that of the gate and the sock stain, you decided to change your opinion concerning your interpretation of the graphs on the sock stain so that you could say that it was from preserved blood?
Clark's central accusation: that Rieders retroactively shifted his testimony after learning inconvenient data, implying bias toward the defense.
Dr. Fredric Rieders
No, that is absolutely misleading and incorrect.
Rieders' flat denial of Clark's allegation that he changed his opinion to accommodate the defense narrative.

Evidence (6)

Informal
Dr. Rieders' July 17th report on EDTA findings in sock and gate stains
Discussed and challenged — Clark highlights that it shows only single parent and single daughter ion, not the full daughter spectrum Rieders later testified to seeing
Informal
Mass spectrometry graphs of sock stain and gate stain blood
Discussed — disputed whether they show full or partial daughter spectrum
Informal
FBI Agent Martz's unpreserved blood test results showing similar EDTA ion profile to gate and sock stains
Discussed — Clark uses it to argue Rieders' original findings were not distinguishing preserved from unpreserved blood
Informal
Merck index entry on calcium disodium EDTA as food preservative
Referenced by Clark to challenge Rieders' characterization of EDTA's uses
Informal
Foreman and Trujillo study on EDTA levels in normal healthy persons
Cited by Rieders to establish baseline EDTA levels below detection thresholds
Informal
Technical literature from Finnegan and Hewlett Packard on MS/MS instrumentation
Referenced by Rieders to defend his single parent/single daughter ion identification standard

Notable Exchanges (4)

Marcia ClarkDr. Fredric Rieders
Extended back-and-forth over whether Rieders changed his interpretation of the sock stain graphs after learning of Martz's unpreserved blood results — Clark implying post-hoc rationalization, Rieders denying it flatly.
accusatory
Marcia ClarkDr. Fredric Rieders
Lengthy technical debate over detection vs. identification in forensic mass spectrometry, including what constitutes a sufficient basis for identifying a compound versus merely detecting it.
strategic
Marcia ClarkDr. Fredric Rieders
Clark presses Rieders on whether he sets his own scientific standards and whether he would change his opinion if the broader scientific community disagreed — Rieders holds firm but his answers invite the inference that he operates by his own rules.
pointed
Marcia ClarkDr. Fredric Rieders
Clark walks through four types of EDTA to establish that EDTA has common non-blood sources (food preservatives, lead poisoning treatment), chipping away at the uniqueness of EDTA as an indicator of preserved blood.
methodical

Credibility Attacks (3)

⚔ Dr. Fredric Rieders
Prior inconsistent statement / opinion evolution
Clark highlights that Rieders' July 17th report did not mention the full daughter spectrum on the sock, but he testified to seeing it on July 24th — after learning of Martz's inconvenient unpreserved blood results. She implies the opinion change was motivated by the need to maintain the defense's planted-blood theory.
⚔ Dr. Fredric Rieders
Methodological challenge / self-referential standards
Clark pressed Rieders repeatedly on whether his identification standard (single parent + single daughter ion) is shared by the scientific community or self-devised, attempting to portray him as an outlier operating outside accepted forensic norms.
⚔ Dr. Fredric Rieders
Impeachment by language of own report
Clark points to Rieders' use of the phrase 'consistent with, indicative of and presumptive for' in his own report — never 'identified' — to argue that even by his own written findings, the EDTA presence was not confirmed as coming from a preserved blood tube.

Objections

7 objections (2 sustained, 5 overruled)
Proceeding 7298 • 138 utterances • Defense witness
Criminal Trial
Department 103
⚖️ Start
📂 AUG 14, 1995 📄 Cross-examination of Dr. Fredr
AUG 14, 1995 KRT DvH TD