📄 Cross-examination of Dr. John Gerdes (part 1) — Friday, August 4, 1995
Address:
C:\DEPT103\CRIMINAL\1995\AUG\4\CROSS-EXAMINATION-OF-DR-JOHN-G.DOC
TRIAL
▲ Day 129 of 167

Cross-examination of Dr. John Gerdes (part 1)

Witness: Dr. John Gerdes
Examiner: George Clarke
Called by: Defense • Date: Friday, August 4, 1995 • Utterances: 444
Prosecution's George Clarke resumes cross-examination of defense DNA expert Dr. John Gerdes, systematically dismantling his contamination theory by tracing the chain of custody of key Bundy blood drops (items 48, 50, 52) and Bronco console stains (303, 304, 305). Clarke establishes that separate swatches from each evidence item were independently sent to Cellmark and the Department of Justice — labs that never involved Yamauchi's extraction process — yet all three labs returned DNA results consistent with OJ Simpson. This structural argument significantly undermines Gerdes' claim that cross-contamination during Yamauchi's handling could account for the incriminating DNA results.
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. The record should reflect that we have now been rejoined by all the members of our jury panel. Good morning, ladies and gentlemen.

THE JURY: Good morning.

3 THE COURT:

All right. Dr. Gerdes, would you resume the witness stand, please.

John Gerdes, the witness on the stand at the time of the evening adjournment, resumed the stand and testified further as follows:

4 THE COURT:

All right. Good morning again, doctor.

5 DR. GERDES:

Good morning.

6 THE COURT:

Doctor, sir, you are reminded you are still under oath. And Mr. Clarke, you may continue with your cross-examination.

7 MR. CLARKE:

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

THE JURY: Good morning.

CROSS-EXAMINATION (RESUMED) BY MR. CLARKE

8 MR. CLARKE:

Good morning, Dr. Gerdes.

9 DR. GERDES:

Good morning.

10 MR. CLARKE:

Dr. Gerdes, the day before yesterday you suggested that there might have been cross-contamination on various evidence items in this case, correct?

11 DR. GERDES:

Yes, I did.

12 MR. CLARKE:

And you suggested that that cross-contamination that might have occurred, occurred during the extraction and evidence handling phase by Collin Yamauchi, correct?

13 MR. SCHECK:

Objection to the form of the question as argumentative.

14 THE COURT:

Overruled.

15 DR. GERDES:

I stated that it was consistent with that, yes.

16 MR. CLARKE:

Now, those are two different steps in the process, correct, that is, sample handling and evidence--I'm sorry, DNA extraction?

17 DR. GERDES:

Yes.

18 MR. CLARKE:

Those two acts or events take place in different rooms at the Los Angeles Police Department, DNA--at the Los Angeles Police Department crime laboratory?

19 DR. GERDES:

They do.

20 MR. CLARKE:

Where does the sample handling take place?

21 DR. GERDES:

That would be in the evidence handling room.

22 MR. CLARKE:

Evidence processing room?

23 DR. GERDES:

Evidence processing room, yes.

24 MR. CLARKE:

Or EPR as it is sometimes referred to in this case?

25 DR. GERDES:

Yes.

26 MR. CLARKE:

DNA extraction takes place where?

27 DR. GERDES:

That is in the serology laboratory.

28 MR. CLARKE:

Now, Dr. Gerdes, you would agree, wouldn't you, that there is a way, by tracing the history of samples and how they are processed and handled, to eliminate one or both of those possibilities of cross-contamination, whether in sample handling or extraction, by looking at the history of a particular evidence sample?

29 DR. GERDES:

I'm not sure. No, I don't believe you can do that. I said that the two controls--to explain this, the two controls, the amplification water control, tends to be a control for introduction of contamination at that stage and that particular control allows you to differentiate from that stage on the process of copying the DNA and anything preceding that. Now, there really isn't a good control to differentiate the first two steps, which is sample handling and sample extraction, at least in the laboratory. Now, the substrate control would allow you theoretically to determine if extract--if there was DNA introduction earlier. If, for instance, the substrate controls were contaminated, and all of the reagent blanks were clean around the same time, that would be definite indication that the source or the time at which the contamination occurred would be at the crime scene.

30 MR. CLARKE:

Dr. Gerdes, going back to my question, isn't there a way, by tracing the history of a particular evidence sample, to eliminate the possibility that cross-contamination occurred at one or both of those two stages?

31 DR. GERDES:

No. The problem is that when you get to the final process, the final typing strip, if you see an indication of DNA on that strip, you have some idea as to what stage it might have been incorporated, but there is no proof because basically, for instance, the extraction blank, if it were contaminated, that basically tells you that something occurred in the handling in the laboratory or in the extraction process, but if the substrate control was contaminated, that could be either because it was contaminated at the--at the crime scene or the reagents that were added to that substrate control at the lab introduced DNA, so that is--

32 THE COURT:

Ask the question again.

33 MR. CLARKE:

Thank you.

34 MR. CLARKE:

Dr. Gerdes, what I'm asking you is isn't there a way, by tracing the history of a sample, that may eliminate one or both of those possibilities of cross-contamination during handling and/or extraction?

35 DR. GERDES:

You can analyze the sequence of events, if that is what you are getting at.

36 MR. CLARKE:

All right. So instead of the history of a sample, you prefer the term "Sequence of events"?

37 DR. GERDES:

Yes.

38 MR. CLARKE:

You are familiar with item no. 48, one of the blood drops at Bundy, correct?

39 DR. GERDES:

Correct.

40 MR. CLARKE:

Describe for us the sequence of events with regard to item no. 48.

41 DR. GERDES:

Okay. Item no. 48, if I recall correctly, came in on the 13th of June, was handled at the processing room for drying on the 14th of June. That particular item was processed at the same time as Mr. Simpson's reference sample and the Rockingham glove.

42 MR. CLARKE:

Well, objection. Move to strike the last portion of the answer.

43 THE COURT:

Overruled.

44 MR. CLARKE:

Is that the entire history?

45 DR. GERDES:

Yes. In the sequence in which that occurred was that the--Mr. Simpson's blood sample was handled first and then the Rockingham glove and then the item 52 and I don't remember the exact sequence, I can look it up, but the other Bundy drops after that.

46 MR. CLARKE:

Is that the entire sequence of events with respect to item no. 48 and DNA testing?

47 DR. GERDES:

There were also substrate controls that were processed at the same time.

48 MR. CLARKE:

Is that--

49 DR. GERDES:

That were done at that time as far as the cuttings.

50 MR. CLARKE:

Is that the entire DNA history of item no. 48?

51 DR. GERDES:

No. At that point that item was--and at this point I will have to look at my notes.

52 MR. CLARKE:

All right. Would it refresh your recollection to look at your notes?

53 DR. GERDES:

Yes.

54 (Brief pause.)
55 (Discussion held off the record between the Deputy District Attorneys.)
56 DR. GERDES:

Okay. On the 24th of June the item 48 and--was mailed to Cellmark and it was mailed at the same time as 49, 50, the reference samples from all three individuals, and no. 7 and 12 which are blood drops from Rockingham and item 47, 52, 56 and 78. Those items were mailed in a package from LAPD on 6/24/94 to Cellmark. The Department of Justice item 48 was mailed to the Department of Justice on August 12th, 1995, and it was mailed at the same time as item no. 6, which is a blood drop from the Rockingham driveway, and items 47, 49 and 50, as well as the reference samples from Mr. Simpson, Nicole Simpson and Ron Goldman.

57 MR. CLARKE:

Is that the entire history of those samples as far as DNA testing is concerned, doctor?

58 DR. GERDES:

They were then analyzed at those particular laboratories and the substrate controls for those particular items for the Department of Justice substrate controls.

59 MR. CLARKE:

I'm sorry, your Honor. Objection, motion to strike.

60 THE COURT:

Sustained.

61 MR. SCHECK:

What about the item, your Honor? He should be allowed to explain it.

62 THE COURT:

Sustained. Sustained.

63 MR. CLARKE:

With respect to item no. 48, is that the entire history as far as DNA testing is concerned?

64 DR. GERDES:

If you want me to go in the specific dates in which the DNA was analyzed, et cetera.

65 MR. SCHECK:

Your Honor, I think this question is vague in the form that he is talking about--

66 THE COURT:

Sustained. Rephrase the question.

67 MR. CLARKE:

Dr. Gerdes, with regard to--

68 THE COURT:

That is also a speaking objection.

69 MR. SCHECK:

I apologize.

70 MR. CLARKE:

Dr. Gerdes, with regard to item no. 48, you have described it being seized. How many swatches were seized--collected?

71 DR. GERDES:

Well, I don't recall right off and I apologize, but I only brought what I felt were critical items to--I mean, I have two file drawers full of data on this and I would have to look it up and I don't have it with me.

72 MR. CLARKE:

As far as these two swatches--I'm sorry. Rephrase that. I would like you to assume that there were two swatches collected with regard to item no. 48 at the crime scene.

73 DR. GERDES:

Okay.

74 MR. CLARKE:

With regard to those swatches--

75 MR. SCHECK:

Objection to that hypothetical in terms of what was collected at the crime scene.

76 THE COURT:

Sustained.

77 MR. CLARKE:

As far as what was collected from item no. 48, how many swatches did in fact Collin Yamauchi deal with when he extracted DNA from it--from one or more of them?

78 DR. GERDES:

I believe, umm--

79 (Discussion held off the record between the Deputy District Attorneys.)
80 DR. GERDES:

Again, I don't have that record with me. I can look that up.

81 MR. CLARKE:

You are unable to tell us today--

82 DR. GERDES:

How many swatches, no.

83 MR. CLARKE:

All right. With regard to item no. 48, is it your recollection, is it your testimony that all of the swatches were in fact processed by Mr. Yamauchi, and I'm referring to DNA extraction?

84 DR. GERDES:

Yes.

85 (Discussion held off the record between the Deputy District Attorneys.)
86 MR. CLARKE:

Incidentally, Dr. Gerdes, do you believe the number of swatches that are collected with respect to a particular stain is important?

87 DR. GERDES:

I believe it is important to keep track of how many there are and it is important--it would be important if they are--to--the ideal situation would be to take those swatches and put them in separate bindles at the time of collection so that they are not handled.

88 MR. CLARKE:

Objection, move to strike, nonresponsive.

89 THE COURT:

Overruled. Ask again.

90 MR. CLARKE:

With regard to, Dr. Gerdes, these one or more swatches, it is your testimony Mr. Yamauchi extracted DNA from whatever was collected, whether it was one or if it was two, he extracted from both of them?

91 DR. GERDES:

He--I'm sure he did not extract from all of the swatches that were collected. It is important to reserve some of that evidence and I'm sure he did that.

92 MR. CLARKE:

Wouldn't it be very important to know, in terms of your opinions about cross-contamination, whether or not he in fact did extract DNA from some of them, all of them or none of them?

93 DR. GERDES:

It would be--it would be important in terms of whether he handled all of them.

94 MR. CLARKE:

Well, wouldn't it be extremely important in terms of the potential of cross-contamination for you to know exactly how many of those swatches he took DNA from?

95 DR. GERDES:

It would be--basically important in terms of--of--it is not important in terms of what I see on the typing results that have been reported. It is important in terms of the potential to go back, at least to the stage in the lab, and perhaps do further analysis. It still doesn't control for what happened before that and it doesn't control for the fact that those swatches--it is my understanding that they were all handled, they were all packaged at the same time. It doesn't matter how many swatches there were there on that morning of--or on the evening of June 13th when they were packaged and bindled, those items were all handled at the same time. And so at this point, since I don't know exactly--or I can't be assured exactly of how those were handled and manipulated, at that point you have--already have a suspicion or may have a suspicion as to the handling of the samples because they were all handled, the swatches were all handled at that time. A subset of those may have been extracted at a later time, but because they were all handled together on that day and because they were all handled together at the crime scene, you can't back this up all the way to the very, very beginning.

96 MR. CLARKE:

Dr. Gerdes, wouldn't it be extremely important to know, in terms of the potentials of cross-contamination, if Mr. Yamauchi extracted DNA from all of those swatches or only some of those swatches?

97 DR. GERDES:

It would be important in terms of going back to those swatches and perhaps doing something with those again, but as far as the analysis of the data that I've looked at, it is not important to that. What I'm looking at is the typing result that he obtained from that and the manipulation, not the extraction, but the manipulation of those swatches on that morning.

98 MR. CLARKE:

Is it your testimony that the steps in extracting DNA from a sample represent the exact same steps that are taken when one simply packages a sample for shipment to another laboratory?

99 DR. GERDES:

No. It is my testimony that the manipulation process has the potential, whenever you manipulate these. It doesn't have to be DNA extraction.

100 MR. CLARKE:

Objection, nonresponsive, your Honor.

101 THE COURT:

Sustained.

102 MR. CLARKE:

Move to strike.

103 THE COURT:

The answer is stricken.

104 MR. CLARKE:

Dr. Gerdes, what I'm asking you is are the steps of extracting DNA from a swatch the same exact steps that are taken when a swatch is simply packaged for shipment to another laboratory?

105 DR. GERDES:

The DNA extraction procedures are similar in all of those laboratories.

106 MR. CLARKE:

No. What I'm asking you, Dr. Gerdes, is are the steps the same for one, taking a sample and extracting DNA from it, and two, simply collecting a sample from a storage location and sending it to another laboratory?

107 DR. GERDES:

The steps should be the same and that includes handling that substrate control in parallel between each evidence item that is handled.

108 MR. CLARKE:

Dr. Gerdes, aren't there steps in extracting DNA that include adding reagents, for instance, to a swatch?

109 DR. GERDES:

Yes.

110 MR. CLARKE:

Aren't there steps that include, for instance, adding chelex to a swatch?

111 DR. GERDES:

Yes.

112 MR. CLARKE:

When one simply grabs a sample from storage and packages it for shipment to another laboratory is chelex added to it?

113 DR. GERDES:

No, but the sample is handled, it is manipulated with gloved hands.

114 MR. CLARKE:

Objection, nonresponsive, your Honor.

115 THE COURT:

Sustained.

116 MR. CLARKE:

Move to strike the answer.

117 THE COURT:

The answer is stricken.

118 MR. CLARKE:

Dr. Gerdes, when you pick a sample up from storage, put it in a box and send it to another laboratory, you don't add any chemicals to it, do you?

119 DR. GERDES:

No.

120 MR. CLARKE:

You don't add chelex to it?

121 DR. GERDES:

No.

122 MR. CLARKE:

You don't put it in a microcentrifuge and spin it around?

123 DR. GERDES:

No.

124 MR. CLARKE:

You just put the sample in a container and ship it?

125 DR. GERDES:

That's correct.

126 MR. CLARKE:

It is never exposed to an extraction process, correct, under the situation I have just described?

127 DR. GERDES:

Under what I've described that's true.

128 MR. CLARKE:

Now I would like to turn your attention to item no. 50. Can you describe the history of that sample, and that is referring to item no. 50, another blood drop at the crime scene?

129 MR. SCHECK:

Your Honor, I think that that is vague, the term "History."

130 THE COURT:

Overruled. In the context of what we've just heard, I know exactly what is coming.

131 (Discussion held off the record between the Deputy District Attorneys.)
132 DR. GERDES:

Item--item 50 was handled at that same--as far as manipulation of the swatches, on 6/13, if I recall. As far as bindling, then it was--it was in the first set again, so it was in with that same set of first--of initial LAPD DNA extractions on 6/14 and again in the manipulation stage that particular item at the time of packaging, the order was Mr. Simpson's reference sample, the Rockingham glove, item--blood item 52 and then item 48 was one of the other four, I'm not sure which order, but it was one of those subsequent to that as far as the manipulation and handling of that sample and bindling. Then on 6/14 it was one of the items that was set up for DNA extraction and then typed at LAPD and it was mailed--item 50, correct?

133 MR. CLARKE:

Yes.

134 DR. GERDES:

It was mailed again on 6/24 to Cellmark. It was in that--that grouping that I mentioned earlier, and to the Department of Justice--it was mailed again on August 12th to the Department of Justice.

135 MR. CLARKE:

Can you--first of all, is that the entire history of that sample as far as DNA testing is concerned?

136 DR. GERDES:

As far as--as its arrival at laboratories. Of course if you want to go into when it was extracted and so forth at each lab, that is not the entire history, but at that point then it was extracted and typed.

137 MR. CLARKE:

In other words, when these items were received by other laboratories there were steps taken to type those samples?

138 DR. GERDES:

Correct.

139 MR. CLARKE:

How many samples were collected with regard to item no. 50?

140 DR. GERDES:

How many swatches?

141 MR. CLARKE:

Correct, I'm sorry, swatches.

142 DR. GERDES:

Again, I don't have that data sheet with me.

143 MR. CLARKE:

With regard to item no. 50, wouldn't it be important to know how many of the swatches collected were extracted for DNA by Collin Yamauchi?

144 MR. SCHECK:

Your Honor, object to the form of the question.

145 THE COURT:

Overruled.

146 DR. GERDES:

Of--the--basically the extraction process again is the second step in this procedure so what is really critical--

147 MR. CLARKE:

Objection, move to strike, your Honor.

148 THE COURT:

Sustained.

149 MR. CLARKE:

Move to strike.

150 THE COURT:

The answer is stricken in its entirety. The jury is to disregard. Ask the question again.

151 MR. CLARKE:

Dr. Gerdes, listen to my question carefully. As far as the potential of cross-contamination of this item that you described on your direct testimony--

152 DR. GERDES:

Uh-huh.

153 MR. CLARKE:

--wouldn't it be important to know if Collin Yamauchi extracted DNA from all the swatches that were received or just some of them?

154 DR. GERDES:

It would be important as to the potential of contamination from that point on, but that does not control for the entire process of what happened in terms of manipulation and handling at the crime scene prior to that.

155 MR. CLARKE:

So your answer is it would be important?

156 DR. GERDES:

It is one aspect.

157 MR. CLARKE:

Dr. Gerdes, with regard to item no. 52, that is another blood drop at Bundy, correct?

158 DR. GERDES:

Yes.

159 MR. CLARKE:

Can you describe for us the history of that item?

160 DR. GERDES:

That is--I believe I already have. It is in that same exact sequence.

161 MR. CLARKE:

All right. Can you tell us how many swatches were collected for item no. 52?

162 DR. GERDES:

I don't have that information with me.

163 MR. SCHECK:

Your Honor, may the witness have papers to refresh his recollection?

164 THE COURT:

Do you have them to refresh his recollection?

165 MR. SCHECK:

Of course. Right here.

166 MR. CLARKE:

Well, I'm sorry, I think I'm given the right to ask questions.

167 MR. SCHECK:

Your Honor, my objection is to this process. He says he doesn't recollect.

168 MR. CLARKE:

Objection.

169 THE COURT:

Sit down. Sit down. Proceed.

170 MR. CLARKE:

You don't recall independently how many swatches were collected for item no. 52, correct?

171 DR. GERDES:

That's correct.

172 MR. CLARKE:

With regard to that particular item, RFLP results were obtained by Cellmark, correct?

173 DR. GERDES:

That's correct.

174 MR. CLARKE:

With regard to the potential of cross-contamination that you described two days ago, wouldn't it be important to know how many swatches of the ones that were collected were extracted by Collin Yamauchi for DNA?

175 DR. GERDES:

No.

176 MR. CLARKE:

So item 52 is different from item 50.

177 DR. GERDES:

No. What I'm saying is I tried to explain it and that is that you basically--doesn't matter how many swatches, those swatches were all handled together. The number doesn't matter.

178 MR. CLARKE:

Dr. Gerdes, isn't it true some of those swatches were never processed to extract DNA by Collin Yamauchi?

179 DR. GERDES:

They were all manipulated to be bindled.

180 MR. CLARKE:

Dr. Gerdes, isn't it true not all of those swatches were extracted for their DNA content by Mr. Yamauchi?

181 DR. GERDES:

Again, it doesn't matter.

182 MR. CLARKE:

Objection, move to strike.

183 THE COURT:

Ask the question for the third time. Doctor, answer the question.

184 DR. GERDES:

Yes.

185 MR. CLARKE:

Dr. Gerdes, isn't it true Collin Yamauchi did not extract DNA from all of those swatches from the Bundy blood drops?

186 DR. GERDES:

Some of those were extracted from different individuals at different labs.

187 MR. CLARKE:

Collin Yamauchi didn't extract DNA from some of those samples, correct?

188 DR. GERDES:

Correct.

189 MR. CLARKE:

Your Honor, I have a series of slides that I would ask to be marked as--

190 THE COURT:

Proceed.

191 MR. CLARKE:

--People's next order.

192 THE CLERK:

564.

193 THE COURT:

564. Do you want the series as 564?

194 MR. CLARKE:

Thank you. And I have previously shown them to counsel and I would ask that the first one be displayed.

195 (Peo's 564 for id = series of slides)
196 THE COURT:

Proceed.

197 MR. CLARKE:

Now, Dr. Gerdes calling your attention to--can you see the slide?

198 DR. GERDES:

May I step down, your Honor? That would be easier from down here.

199 THE COURT:

Sure.

200 MR. CLARKE:

For the record, your Honor, this first slide that will be part of People's 564, does the Court wish them to be lettered individually?

201 THE COURT:

Yes.

202 MR. CLARKE:

All right. This would be 564-A entitled "Replicate DQA testing of items, 48, 50, 52."

203 (Peo's 564-A for id = slide)
204 MR. CLARKE:

And for purposes of describing this slide A, Dr. Gerdes, does it basically have what appear to be two symbols or a house or building?

205 DR. GERDES:

Yes.

206 MR. CLARKE:

The bottom of which is labeled "EPR" and the notation to the left "6/13 drying."

207 DR. GERDES:

Yes, I see that.

208 MR. CLARKE:

And then an arrow to an icon or symbol again labeled "EPR" and to the left labeled "6/14 sampling"?

209 DR. GERDES:

That is what it says.

210 MR. CLARKE:

All right. Is it correct then that with regard to those three items, that they were in fact dried in the evidence processing room or EPR on June 13th, that drying process began?

211 DR. GERDES:

That's true.

212 MR. CLARKE:

And is it also true that on the next day, June 14th, in the same room, the evidence processing room, that those particular or at least one of those particular swatches from those samples were sampled by Mr. Yamauchi?

213 DR. GERDES:

That's true.

214 MR. CLARKE:

Is that consistent with your understanding of the events in this case?

215 DR. GERDES:

That is my understanding.

216 MR. CLARKE:

All right. Your Honor, with the Court's permission I would like to display the next slide which would be B.

217 (Peo's 564-B for id = slide)
218 MR. CLARKE:

And B for the record contains a symbol.

219 THE COURT:

Additional icon marked "Serology."

220 MR. CLARKE:

Thank you.

221 MR. CLARKE:

Now, Dr. Gerdes, isn't it correct that from June 14th and in particular from that portion of the samples from items 48, 50 and 52 which were sampled by Mr. Yamauchi, that they went into the serology section and DNA was extracted by Mr. Yamauchi?

222 DR. GERDES:

That's correct, as I understand it.

223 MR. CLARKE:

It is your understanding also that what went on June--excuse me--that what went from the evidence processing room to the serology room was not all of the swatches that were in fact collected on June 13th?

224 DR. GERDES:

That's my understanding.

225 MR. CLARKE:

All right. Then if we could have what will be labeled exhibit C, I'm sorry, slide C.

226 (Peo's 564-C for id = slide)
227 MR. CLARKE:

Which has added another symbol labeled "Parker Center."

228 DR. GERDES:

Yes.

229 MR. CLARKE:

Is it also correct that as part of the DNA typing process of portions of some of the swatches, that following the extraction of DNA that DNA that had been extracted by Mr. Yamauchi was taken to Parker Center for the amplification portion of the test?

230 DR. GERDES:

That's true.

231 MR. CLARKE:

And in fact that amplification portion also includes the development of the strips so that results can be read, right?

232 DR. GERDES:

That's true.

233 MR. CLARKE:

And even photography as well to record those results so that they can be reviewed later?

234 DR. GERDES:

That's true.

235 MR. CLARKE:

Is this in fact, slide C, an accurate representation of the chain of events for a portion of some of the swatches of items 48, 50 and 52?

236 DR. GERDES:

It is.

237 MR. CLARKE:

All right. Slide D then with the Court's permission.

238 THE COURT:

Yes.

239 (Peo's 564-D for id = slide)
240 MR. CLARKE:

What this slide has added, Dr. Gerdes, is two symbols to the right of the June 14th sampling EPR symbol which read "ECU and serology," correct?

241 DR. GERDES:

That's what it says, yes.

242 MR. CLARKE:

And is it--it is true, is it not, that portions of the remaining swatches not sampled, not extracted by Collin Yamauchi, were sent to the evidence control unit?

243 DR. GERDES:

I believe that is true.

244 MR. CLARKE:

Portions of those remaining portions were returned to the serology unit for purposes of shipment; isn't that correct?

245 DR. GERDES:

On that date?

246 MR. CLARKE:

No. As far as the date, I don't want to you assume that it was on June 14th that the sampling date occurred.

247 DR. GERDES:

At a later date, that's true.

248 MR. CLARKE:

All right. And your Honor, I it will be slide E.

249 (Peo's 564-E for id = slide)
250 MR. CLARKE:

You described, Dr. Gerdes, and I believe you described the date of June 4th that again portions of the original swatches were sent to Cellmark, correct?

251 DR. GERDES:

That's correct.

252 THE COURT:

We're talking 48, 50 and 52 still, correct.

253 MR. CLARKE:

And that would be true for items 50?

254 MR. SCHECK:

Your Honor, I would object to the term "Portions" as opposed to "Swatches."

255 THE COURT:

Swatches.

256 MR. CLARKE:

All right. Dr. Gerdes, what was sent as far as items 48, 50 and 52 to Cellmark that you described I believe on June 4th?

257 DR. GERDES:

They were swatches of those particular items.

258 MR. CLARKE:

Those were not swatches that Collin Yamauchi had extracted DNA from, were they?

259 DR. GERDES:

They are not the--the swatches that he extracted DNA from, no.

260 MR. CLARKE:

All right. Then slide F, your Honor.

261 (Peo's 564-F for id = slide)
262 MR. CLARKE:

And I believe it could be characterized as including an arrow down from the symbol Cellmark to a circle containing DOJ.

263 MR. CLARKE:

Is that a fair description, doctor?

264 DR. GERDES:

Yes.

265 MR. CLARKE:

With regard to item no. 52, it is correct, is it not, that a swatch or swatches were sent from Cellmark to the Department of Justice for testing, correct?

266 DR. GERDES:

I believe that's true.

267 MR. CLARKE:

And in fact were ultimately typed by the Department of Justice?

268 DR. GERDES:

Yes.

269 MR. CLARKE:

Dr. Gerdes, with regard to those samples, and I'm referring to the swatches that were never extracted by Collin Yamauchi, they were never subjected to cross-contamination that you have described that can occur during the extraction of DNA process, correct?

270 DR. GERDES:

They were not subjected to that at that third step in the process.

271 MR. CLARKE:

In other words, the swatches that went to Cellmark and the Department of Justice, and I'm referring now to the arrows that go right as well as to Cellmark and DOJ, they were never subjected to any of those steps by Collin Yamauchi to remove DNA?

272 DR. GERDES:

Not at the extraction stage, but there are earlier stages.

273 MR. CLARKE:

Objection, move to strike the answer, your Honor; nonresponsive.

274 THE COURT:

Sustained. Ask the question again.

275 (Discussion held off the record between the Deputy District Attorneys.)
276 MR. CLARKE:

Dr. Gerdes, isn't it true that what you described yesterday, actually day before yesterday, about what might have happened to those samples that went to Cellmark and DOJ as far as DNA extraction cross-contamination could not have happened?

KEY QUOTE
277 DR. GERDES:

I wouldn't state it--if you restrict it to only the extraction stage, that is true.

KEY QUOTE
278 MR. CLARKE:

You have described the extraction stage as one of those stages that cross-contamination can occur, correct?

279 DR. GERDES:

That's correct.

280 MR. CLARKE:

It could not have happened with the Cellmark and DOJ samples, correct?

281 DR. GERDES:

Not at the extraction stage.

282 MR. CLARKE:

All right. Perhaps you could have a seat again, doctor. Thank you.

283 (Witness complies.)
284 (Discussion held off the record between the Deputy District Attorneys.)
285 MR. CLARKE:

Incidentally, Dr. Gerdes, none of these samples went to simply one laboratory, correct?

286 DR. GERDES:

All of the samples--excuse me. All of the samples went to LAPD, went through LAPD first.

287 MR. CLARKE:

Well, objection, move to strike, nonresponsive.

288 THE COURT:

Ask the question again.

289 MR. CLARKE:

Dr. Gerdes, isn't it true that none of these samples were typed by one laboratory only?

290 DR. GERDES:

Of these three items you are talking about?

291 MR. CLARKE:

Correct.

292 DR. GERDES:

They were all typed by more than one lab.

293 MR. CLARKE:

They were typed by three different laboratories, correct?

294 DR. GERDES:

That's correct.

295 MR. CLARKE:

And they were typed using swatches that weren't even typed by LAPD as far as Cellmark and DOJ?

296 DR. GERDES:

Could you repeat that?

297 MR. CLARKE:

Sure. As far as the swatches typed by Cellmark and the Department of Justice, those swatches weren't even typed by the Los Angeles Police Department, correct?

298 DR. GERDES:

Those swatches?

299 MR. CLARKE:

The individual swatches?

300 DR. GERDES:

The items were; the swatches weren't.

301 MR. CLARKE:

Incidentally, as far as the results from items 48, 50 and 52, and I'm referring to the DNA results, they all could have come from Mr. Simpson, correct?

302 DR. GERDES:

In terms of what is reported as results?

303 MR. CLARKE:

In terms of--

304 DR. GERDES:

Yes.

305 MR. CLARKE:

In terms of what was reported by the LAPD?

306 (Brief pause.)
307 (Discussion held off the record between the Deputy District Attorneys.)
308 DR. GERDES:

That's definitely true for item 52 for LAPD. That is true for item 50. The reason I'm checking is that there were some with very faint C dots that they didn't call. Yes, that is true for that third item, too.

309 MR. CLARKE:

So items, 48, 50 and 52 all revealed DNA results by the Los Angeles Police Department consistent with Mr. Simpson?

310 DR. GERDES:

Yes.

311 MR. CLARKE:

As far as Cellmark was concerned, they tested all three items as well, didn't they?

312 DR. GERDES:

Yes.

313 MR. CLARKE:

Those results were all consistent with Mr. Simpson, correct?

314 DR. GERDES:

They were.

315 MR. CLARKE:

As far as items 48, 50 and 52 by Gary Sims and the Department of Justice, those results with all consistent with Mr. Simpson, correct?

KEY QUOTE
316 DR. GERDES:

That's correct.

317 MR. CLARKE:

Now, you suggested day before yesterday that there might have been cross-contamination of certain evidence items other than 48 through 52, correct?

318 DR. GERDES:

Yes.

319 MR. CLARKE:

Dr. Gerdes, isn't it true there are evidence items in this case that were never even touched by Collin Yamauchi?

320 DR. GERDES:

The--yes, that is true.

321 MR. CLARKE:

Isn't it true there are evidence items never even touched by Dennis Fung?

322 DR. GERDES:

They are all going through the same laboratory.

323 MR. CLARKE:

Objection, nonresponsive, move to strike.

324 THE COURT:

Sustained. The answer is stricken.

325 DR. GERDES:

There are some items, yes.

326 MR. CLARKE:

There are items never been touched by Dennis Fung; isn't that correct?

327 DR. GERDES:

That's true.

328 MR. CLARKE:

There are evidence samples never been touched by Andrea Mazzola?

329 DR. GERDES:

That's true.

330 MR. CLARKE:

There are evidence items that have never even been typed for PCR by the Los Angeles Police Department but have been typed by Cellmark or the Department of Justice?

331 DR. GERDES:

As far as typing, that is true.

332 MR. CLARKE:

As far as those samples that have not been touched by Collin Yamauchi, Dennis Fung and Andrea Mazzola, tell us which samples are those?

333 DR. GERDES:

Again, I don't have my notes on that section of--of the chain of custody, and basically I'm basing that on what I recall from their testimony.

KEY QUOTE
334 MR. CLARKE:

Okay. Wouldn't it be important to know who touched certain items as far as collecting evidence, let's say, as far as the potential of cross-contamination?

335 DR. GERDES:

It would--it might be important in terms of tracing it to a single individual, but basically I didn't attempt to trace it to a single individual. It is traced to--what the point is, is there is--from looking at any of those individuals and the record of the laboratory in terms of contamination, there is substantial risk, and I have no confidence--

336 MR. CLARKE:

Objection, move to strike, nonresponsive.

337 THE COURT:

Overruled.

338 DR. GERDES:

And so therefore I did not attempt.

339 THE COURT:

That is the end. Next question?

340 DR. GERDES:

Excuse me.

341 MR. CLARKE:

May I have a moment, your Honor?

342 (Discussion held off the record between the Deputy District Attorneys.)
343 MR. CLARKE:

Dr. Gerdes, as far as the potential of cross-contaminating another sample, it is different to extract DNA from it than it is to simply package it for shipment in terms of this risk of contamination of individuals?

344 THE COURT:

We have already asked that question.

345 MR. CLARKE:

All right.

346 MR. CLARKE:

As far as these samples that were not processed by any of these individuals--and I have mentioned Collin Yamauchi, Dennis Fung and Andrea Mazzola, correct?

347 DR. GERDES:

Yes.

348 MR. CLARKE:

As far as all of those samples, you cannot recall now which samples those are; is that right?

349 DR. GERDES:

I have a clear--I know that the samples which are the Bundy blood drops, the Rockingham glove and Mr. Simpson's reference sample were handled by Collin Yamauchi. I have a definite absolute positive--I'm positive of that. As far as other samples, such as the sock and perhaps some of the--the other items, I don't have as clear of a recall--recollection of those.

350 MR. CLARKE:

You discussed during your direct examination three items removed from the Bronco automobile, items no. 303, 304 and 305. Do you recall that?

351 DR. GERDES:

I do.

352 MR. CLARKE:

Can you describe for us the history of those items?

353 DR. GERDES:

Yes. Those were collected in June, June 14th, I believe, and those were processed, umm, and extracted on June 15th.

354 MR. CLARKE:

Who collected those items, 303, 304 and 305, and I'm referring to collecting the bloodstains?

355 DR. GERDES:

Umm--

356 MR. SCHECK:

Your Honor, which--

357 MR. CLARKE:

Excuse me. Objection, your Honor, speaking objection.

358 THE COURT:

Sustained.

359 MR. CLARKE:

I'm sorry.

360 THE COURT:

Proceed.

361 DR. GERDES:

I don't recall who collected them out of the Bronco itself.

362 MR. CLARKE:

So you don't recall who collected them on June 14th?

363 DR. GERDES:

No.

364 MR. CLARKE:

Who typed them?

365 DR. GERDES:

They were typed by Collin Yamauchi on the 15th of June.

366 MR. CLARKE:

What were the results by Mr. Yamauchi from items 303, 304 and 305?

367 DR. GERDES:

303?

368 MR. CLARKE:

303, 304 and 305?

369 DR. GERDES:

I'm sorry, I thought you were talking about the earlier items, 23, 25--okay.

370 MR. CLARKE:

I'm sorry, you thought when I said 303--

371 DR. GERDES:

303.

372 MR. CLARKE:

You thought I said 23 and 25?

373 DR. GERDES:

I'm sorry, I'm--let me back up. The items 303--those were collected in--those were the items that were later collected from the Bronco console, so those were the items that were collected at a later date.

374 MR. CLARKE:

When were they collected?

375 DR. GERDES:

In--I believe it was in July. I don't recall the exact date.

376 MR. CLARKE:

It is actually in August, isn't it, Dr. Gerdes?

377 DR. GERDES:

Yes, July or August.

378 MR. CLARKE:

So these three samples, 303, 304 and 305 were not collected in June of 1994?

379 DR. GERDES:

No, they were collected in July or August, excuse me.

380 MR. CLARKE:

They were collected over two months later, weren't they?

381 DR. GERDES:

They were.

382 MR. CLARKE:

You do not recall who collected those samples?

383 DR. GERDES:

Not the individual.

384 MR. CLARKE:

All right. What can you tell us about the sequence of events following that--

385 DR. GERDES:

I'm sorry, I do recall who collected them; Collin Yamauchi.

386 MR. CLARKE:

Is it your testimony that Collin Yamauchi collected the stains from the console 303, 304 and 305?

387 DR. GERDES:

I am not absolutely sure, but I think that is who did that. I don't have the notes with me.

388 (Discussion held off the record between the Deputy District Attorneys.)
389 MR. CLARKE:

Dr. Gerdes, isn't it important to know who collected these items in view of your testimony about the potential of cross-contamination?

390 DR. GERDES:

Not in my opinion. Basically it is important how they were collected; not who collected them.

391 MR. CLARKE:

Isn't it true Michele Kestler collected those samples?

392 DR. GERDES:

That may be.

393 MR. CLARKE:

In your opinion that makes no difference?

394 DR. GERDES:

It makes--I have observed the testimony of each of these individuals on their procedures as to how they collect items. In my opinion none of the individuals are collecting these in a manner that a microbiologist would consider safe and therefore I don't recall the details frequently on who did it. They are all equally risky.

395 MR. CLARKE:

So it is your testimony that all of the individuals in this case and who have been involved in collecting evidence are all risky as you have used the term?

396 DR. GERDES:

In terms of what they've described as their collection methods at the crime scene, yes.

397 MR. CLARKE:

As far as 303, 304 and 305, what are the sequence of events after their collection?

398 DR. GERDES:

Okay. Those items were sent to the Department of Justice after being processed at the LAPD and they were received there on September 26th.

399 MR. CLARKE:

Were these samples typed by the Los Angeles Police Department?

400 DR. GERDES:

No.

401 MR. CLARKE:

Did they have DNA extracted by the Los Angeles Police Department?

402 DR. GERDES:

No.

403 MR. CLARKE:

Were they processed as far as any steps in preparation to extract DNA, for instance, in the serology section of the Los Angeles Police Department?

404 DR. GERDES:

They were processed in terms of bindling and packaging.

405 MR. CLARKE:

Now, those samples were then typed, correct, by the Department of Justice?

406 DR. GERDES:

Correct.

407 MR. CLARKE:

All right. Your Honor, I have a slide actually in the form of a copy to place on the elmo that I would ask be marked as the People's next exhibit in order, a copy of which I have provided to the Defense.

408 THE COURT:

565.

409 MR. CLARKE:

565.

410 (Peo's 565 for id = slide)
411 DR. GERDES:

May I step down, your Honor?

412 THE COURT:

Yes.

413 MR. CLARKE:

All right. Dr. Gerdes, perhaps this item can be described as a title "DNA testing of items 303, 304, 305 Bronco console."

414 DR. GERDES:

Yes.

415 THE COURT:

Is this--is this something known as a flow chart?

416 MR. CLARKE:

Yes. I think that would be a good description, flow chart.

417 MR. CLARKE:

Now, the first box to the left, Dr. Gerdes, describes "Bronco console removed during search"; is that correct?

418 DR. GERDES:

Yes, yes.

419 MR. CLARKE:

With a date of August 26th, 1994?

420 DR. GERDES:

Yes.

421 MR. CLARKE:

And to your--from your review of the record does that appear to be an accurate description of what occurred on that date?

422 DR. GERDES:

That is--yes.

423 MR. CLARKE:

The flow chart then has a second box to the right labeled "September 1, `94" and inside that box swatches made from console in serology, correct?

424 DR. GERDES:

Yes.

425 MR. CLARKE:

And does that in fact describe accurately what occurred with regard to items 303, 304 and 305?

426 DR. GERDES:

I believe that does, yes.

427 MR. CLARKE:

Your only hesitation; is that right, is just as to the date?

428 DR. GERDES:

That's right. I didn't remember the date.

429 MR. CLARKE:

The next box then shows "Swatches sent to Department of Justice 9/26/94"; is that right?

430 DR. GERDES:

I don't recall the date exactly, but I believe I just read that off, so yes.

431 MR. CLARKE:

And as far as--

432 DR. GERDES:

That is what I just said, yes.

433 MR. CLARKE:

As far as you know that is accurate?

434 DR. GERDES:

Yes.

435 MR. CLARKE:

And then the next box shows "11/22/94 no. 305 returned to LAPD"?

436 DR. GERDES:

Correct.

437 MR. CLARKE:

Had the Department of Justice done anything with regard to item no. 305 as of November 22nd, 1994?

438 DR. GERDES:

I would have to check my notes, but--let me check.

439 MR. CLARKE:

All right. Would you please, if that would refresh your memory.

440 (Witness complies.)
441 MR. SCHECK:

Your Honor, could we approach for a minute on something?

442 THE COURT:

On this exhibit?

443 MR. SCHECK:

What? We have to discuss--

444 THE COURT:

With the court reporter, please.

Temperature

tense

Key Quotes (5)

George Clarke
Dr. Gerdes, isn't it true that what you described yesterday, actually day before yesterday, about what might have happened to those samples that went to Cellmark and DOJ as far as DNA extraction cross-contamination could not have happened?
The crux of Clarke's cross — forcing Gerdes to concede that the contamination theory doesn't apply to the independently-tested samples.
Dr. John Gerdes
I wouldn't state it--if you restrict it to only the extraction stage, that is true.
Gerdes' partial concession that Yamauchi-related extraction contamination cannot explain the Cellmark and DOJ results.
Dr. John Gerdes
In my opinion none of the individuals are collecting these in a manner that a microbiologist would consider safe and therefore I don't recall the details frequently on who did it. They are all equally risky.
Gerdes broadens his attack to every evidence collector, but the sweeping claim undermines his specificity and credibility.
George Clarke
As far as items 48, 50 and 52 by Gary Sims and the Department of Justice, those results were all consistent with Mr. Simpson, correct?
Clarke locks in the triple-lab confirmation — LAPD, Cellmark, and DOJ all matched Simpson, delivered to the jury as a clean series of admissions.
Dr. John Gerdes
Again, I don't have my notes on that section of--of the chain of custody, and basically I'm basing that on what I recall from their testimony.
Recurring admission that undercuts Gerdes' authority as an expert — he repeatedly lacks the records to support his own analysis.

Evidence (6)

People's 564-A through 564-F
Series of slides depicting the chain of custody and DNA testing flow for items 48, 50, and 52 (Bundy blood drops), showing EPR drying, serology extraction, Parker Center amplification, and shipment to Cellmark and DOJ
introduced and discussed with witness
People's 565
Flow chart titled 'DNA testing of items 303, 304, 305 Bronco console,' tracing collection (8/26/94), swatch preparation (9/1/94), DOJ shipment (9/26/94), and item 305 return to LAPD (11/22/94)
introduced and discussed with witness
Informal
Items 48, 50, 52 — Bundy crime scene blood drops
central to contamination argument; chain of custody traced in detail
Informal
Items 303, 304, 305 — blood stains from Bronco console, collected August 1994
discussed; Gerdes confused dates and collector identity
Informal
Rockingham glove — processed alongside Bundy drops and Simpson reference sample on 6/14
referenced in contamination sequencing
Informal
OJ Simpson reference blood sample — handled first in the 6/14 sequence before Bundy drops
referenced as potential contamination source

Notable Exchanges (4)

George ClarkeDr. John Gerdes
Clarke walks Gerdes through slides A–F establishing that separate swatches from items 48, 50, 52 went to Cellmark and DOJ without ever being touched by Yamauchi in the extraction process — and that all three labs got the same result. Gerdes is forced to agree at each step.
strategic
George ClarkeDr. John Gerdes
Clarke repeatedly asks how many swatches were collected for each item; Gerdes repeatedly admits he doesn't have his notes with him. Scheck tries to hand him papers mid-examination; Clarke objects and Ito shuts it down.
revealing
George ClarkeDr. John Gerdes
Clarke asks who collected items 303–305 from the Bronco. Gerdes first says he doesn't recall, then says he thinks it was Yamauchi, then walks it back entirely when Clarke implies it was Michele Kestler. Gerdes' uncertainty about a key factual basis of his testimony is exposed.
revealing
Barry ScheckLance A. Ito
Scheck attempts a speaking objection to help Gerdes when the witness says he can't recall; Ito shuts it down sharply: 'Sit down. Sit down. Proceed.'
heated

Credibility Attacks (3)

⚔ Dr. John Gerdes
lack of preparation / missing records
Clarke repeatedly exposed Gerdes' inability to recall key details — number of swatches collected, who collected Bronco samples, exact dates — because Gerdes did not bring his notes. Gerdes himself acknowledges having 'two file drawers full of data' but not having the relevant records with him.
⚔ Dr. John Gerdes
internal inconsistency
Gerdes initially testified he was 'sure' Yamauchi collected Bronco console items 303–305, then retracted: 'I am not absolutely sure.' Clarke then suggests it was actually Michele Kestler, which Gerdes concedes may be true.
⚔ Dr. John Gerdes
concession under structured cross
Clarke's slide-by-slide approach forced Gerdes to confirm that Cellmark and DOJ swatches were never subjected to Yamauchi's extraction — directly conceding that his contamination theory cannot explain those labs' matching results.

Witness Demeanor

(Witness steps down from stand to view slides on multiple occasions)
(Brief pauses and off-record discussions with co-counsel throughout)
(Witness audibly confused, correcting himself on items 303/304/305 dates and collector identity)
(Witness complies — returning to stand after viewing exhibits)

Objections

22 objections (12 sustained, 6 overruled)
Proceeding 7178 • 444 utterances • Defense witness
Criminal Trial
Department 103
⚖️ Start
📂 AUG 4, 1995 📄 Cross-examination of Dr. John
AUG 4, 1995 KRT DvH TD