All right. Thank you, ladies and gentlemen. Please be seated. All right. Dr. Cotton, would you resume the witness stand.

Robin Cotton, The witness on the stand at the time of the evening adjournment, resumed the stand and testified further as follows:

Let the record reflect we have now been rejoined by all the members of our jury panel. Good morning, ladies and gentlemen.

THE JURY: Good morning.

My apologies to you for the late start this morning. I had a few matters that I had to take up out of your presence, and as you can tell from the nature of the testimony, some of these things involve some rather complicated scientific matters that I had to decide before further evidence was presented to you, so I apologize to you for the delay in getting started. We also had a hard time rounding up all the necessary parties before getting started this morning. Also, I understand we had some modifications to cinema 1 and cinema 2. All right. I take it they are acceptable? All right. You might want to write a thank you note to the king.

Who?

Also, counsel, I have modified the jury box slightly. I have asked everybody in row no. 1 top slide down one seat so that juror no. 1 is protected by the monitors from the errant display boards. All right. That is for juror no. 1's protection. All right. Mr. Clarke, you may resume.

Thank you, your Honor.

Good morning again, ladies and gentlemen.

THE JURY: Good morning.

DIRECT EXAMINATION (RESUMED) BY MR. CLARKE

Dr. Cotton, just briefly, you had described the fact that Dr. Blake had actually performed this cutting process on I believe it was six of the evidence items yesterday?

Yes.

With regard to those cuttings, were you present when they took place?

Yes, I was.

And observed what took place?

Yes.

In your opinion did Dr. Blake do anything that might contaminate those samples by his cutting process?

No.

Now, have you, since we broke yesterday, had an opportunity to look at one of the those boards that I showed you yesterday that dealt with the chain of custody of certain items received in your laboratory?

Yes, I have.

All right.

Referring you to that board that is marked People's exhibit 209, did you have a chance to look at in particular the four items that have your laboratory's name labeled at the far right, which are items 7, 12, 49 and 56?

Yes, I did.

And does that board accurately reflect your laboratory's receipt of those four items on the day after the date on the board which in the case of each of four is April 3, 1995?

Yes. Our records reflect that we received them the day after the date on the board.

All right. Very good. Now, Dr. Cotton, if I could--and I believe we were about to get started on that when we recessed yesterday--with respect to the autorad that has already been marked People's exhibit 246 and which we have made copies or had prepared copies for each of the jurors, which I believe are marked People's exhibit 256, that autorad in fact contains the known DNA from the three parties in this case; is that right?

That's right.

That would include Mr. Simpson?

Yes.

Nicole Brown?

Yes.

And Ronald Goldman?

Yes.

All right. Does that autorad demonstrate any differences in their DNA patterns?

Yes, it does.

Does that autorad also have a particular item of evidence that was tested at the same time?

Yes.

What item is that?

I believe it is item 56.

Is that a shoeprint--I'm sorry, is that actually a blood-stained shoeprint?

That is what you have conveyed to me.

Now, your Honor, it would be my request to hand out, re-hand out these copies for each of the jurors so that they can utilize that during the witness' testimony about this particular x-ray.

Yes. Proceed.

I am actually looking for the earlier marked one, 246. I'm wondering if perhaps it is in the pile with 256.

I don't think so.

I just sent Mrs. Robertson on another errand so--

All right.

256?

246.

246.

All right. Mrs. Robertson has the original.

Thank you. Dr. Cotton, what I'm going to ask you to do--and first of all, have you had an opportunity to see what these x-rays look like when they are projected on to the upper screen?

Yes, I have.

With respect to 246 then would it assist you in describing the results on this particular x-ray to have it on the screen so that you can point out certain things?

Sure.

All right. With the Court's permission then I would like to display People's 246.

Proceed.

And Dr. Cotton, can you step down here and would that aid in your ability to point out particular items on this particular x-ray as well as by using the point maker?

Yes. And maybe if we have one other copy, or the original, we could play it on the small light box also.

All right. Let me ask you a couple questions. You have the original x-rays in this case?

I have the original autorads in this case.

And when we say autorad and x-ray--

X-ray.

--is that the same thing?

Yes.

Okay. You have the originals and then have there been copies provided to both sides in this case?

Yes.

All right. With respect to these originals versus the copies, what differences are there, if any?

The copies may have--for the most part there is no differences. When a band is very light, the copy may not show that band quite as clearly as the original, and the only way to determine that is to hold them side-by-side and see if you can see it as clearly on a copy as you can on the original.

All right. Do we have in fact a small light box also in Court on counsel table?

Yes.

And would it assist you to use that light box to look at the original just in case there are any differences between the original and the copy?

Well, actually what I'm concerned with is how it looks up on the screen as opposed to how it would look on the light box, so that is why that helps me to have the light box there.

All right. Then with the Court's permission we will adopt that procedure and be able to display to the jury on the projection screen itself.

All right. Proceed.

All right. Dr. Cotton, if you could, could you obtain the original of what has been marked People's 246, but also the copies, People's exhibit 256.

Here is the original for this film.

Your Honor, with the Court's permission, prior to discussing, and there aren't very many samples on these autorads, I would like to at least show briefly to the jury the particular item of evidence that has been described by previous witnesses.

Referring specifically to 56?

Exactly, and I believe that particular photo board is exhibit 165.

All right.

Your Honor, I would only make the objection, subject to a clarification from the Court, that again on the chain of custody, that she is not testifying that it is that item.

Correct.

I would just simply ask for that instruction from the Court.

I think that is apparent already from the testimony.

I'm sorry?

It is apparent already from the testimony.

And referring specifically on this exhibit, your Honor, which I believe is People's exhibit 165, in particular to the photograph on the top row, three photos from the left labeled "item no. 56."

Now, Dr. Cotton, with regard to this particular x-ray, first of all, is this an x-ray that was developed following your use of this RFLP typing process?

Yes, it is.

Okay. Could you describe for us what this x-ray shows in broad terms? In other words, how is it oriented, what are the samples on it and so forth?

Okay. Let me just start with telling you that this is the right way to hold it. The dark lettering, or the dark background to the lettering, at the top I want to be up. The lettering across the top is simply the number of the gel that these samples were loaded on. "f" is on there because it is a forensic case and not a paternity case. If it was a paternity case, that would be a "p." 08/09/94 is the date the gel was run on and "15a" is simply the number of the gel tank that the gel was run on. And this lettering is actually essentially burned into the film, that is, it is exposed at the time the film is made, so it can't be erased or taken off in any way, and this is our permanent record that this film goes with a particular case. Now, on your films, although it is not shown on the screen, you can see that there is handwriting at the bottom and that handwriting at the bottom is written on here by the analyst who is doing the test, and he or she is taking that record from the case folder where it is listed, the order that the samples were loaded into the gel, and so these are our sample numbers across the bottom, and then the case number and the gel number is written again and then you see the letters "SLC." That refers to the fact that this film is made with a group of probes and in the lab we call it a cocktail, so it is that--that stands for single locus cocktail. The reason--if you remember in the example that we have talked about so far, we keep talking about for one genetic location you will see two bands. Well, obviously here, and now you can sort of move to the screen, you see that there are multiple bands on--in many of the lanes here, and that is because four different probes were added to this film. This is done in our lab. It is the first addition of probes. And then--and we haven't mentioned this before. Once you add probes to a membrane and you allow them to bind and you get your x-ray film off, you can strip those probes away without moving--removing very much of the DNA on the membrane and come back and then do another probe on that membrane, get another film, finish that, strip that probe off and come back and do it again. And depending on the amount of DNA that you have on that film, you may be able to do that many, many times.

Let me stop you for a moment, Dr. Cotton. When you have described that this particular x-ray includes four different probes done at once--

Yes.

--why do you do that? Why don't you just do one at a time?

If we are comparing evidence samples and known samples and the evidence and the knowns are not consistent, that is, the known people that we have for a case are excluded from being donors of the evidence, that becomes apparent immediately on having a group of four probes like this. So it allows us, if in fact the result is an exclusion, it allows us to see that very clearly right away. We report that right away and then we don't go on any further until we are requested. And we've done our film in the lab this way from the beginning. Most other labs just do them one at a time. This is an instance where there isn't a right or a wrong. This isn't better or worse than anybody else's; it is just customary at Cellmark. Okay. So the next important thing to notice, and I will--we will go to the pen here, okay, this lane on the far left, the second lane in, this middle lane and the two lanes on the right are what are referred to as markers. They are one of the--one of the types of controls that is on an RFLP test. Each--let's talk about this marker first, (Indicating), because it is the easiest to visualize. Each one of these bands is from a DNA fragment whose size is exactly known. The marker is purchased from a biotechnology company, and although I'm not going to remember the exact sizes, I could easily go look them up. And in--as a very close approximation, this band is 2000 base pairs. This one, (Indicating), is 3000--whoops. Let's undo that. So we have 2, 3, 4,000, 5000, 6000, 7000 up here, (Indicating), 8000, 9, 10, 11 and 12. The purpose of that marker is to later on use that with the computer imaging system to help make an estimation of the fragment sizes in the other samples. And as long as we are talking about that, let's just use an example. If this is 2 and this is 3 and this is 4, this band, (Indicating), in Mr. Goldman's pattern is clearly between 3 and 4, and remember that what we are concerned about is the samples were loaded across the top here in about the same positions as the bottom of each of the labels, approximately. And the DNA from each sample moved through the gel, down in this direction, (Indicating), and the smaller pieces would move faster and further through the gel than the longer ones. And that is illustrated again by the marker. Here is this lowest one is about 1600 and then 2000 and so on. So by eye you can make an estimation that this lowest band in Mr. Goldman's pattern is somewhere between 3000 base pairs and 4000 base pairs. Now, the computer system can actually do measurements. The measurements reflect the distance migrated through the gel. And the computer system will then do a calculation that will give you a more precise estimate that you can do just by eye. You don't have to have a computer system to do it. You could measure them yourself and plot it out on a piece of graph paper and your answer would still be quite good. The second marker up here, (Indicating)--well, let me go back to the labels. This marker is labeled 1 KB. It stands for one kilobase. That is each of the bands in that marker is 1000 base pairs larger than the band below it. The second marker is a viral DNA that is commonly used as a marker. It is labeled lambda and really we are only using this top band as a--to give us a band that is larger than 12,000 base pairs. And this top band in lambda is approximately 23,000 base pairs. So this--the combination of this 23,000 base pair and the 1 KB marker is what we are using to estimate sizes. There are two additional samples on this film that does not relate specifically to this case. One of them is over here it is labeled TDS on your film. It is DNA from a blood sample from one of the lab staff at Cellmark. This person has been gracious enough to provide us a blood sample every four or six months or so and we have been using his blood sample as a control sample for a long time. We know exactly what his pattern should look like and we have many measurements of the sizes of the DNA bands in that pattern, and that is an example of one of the controls that I mentioned the other day where we know what this pattern should look like. Should it look different than usual, we would--that is, should the band sizes be different than usual, that would be of concern to us.

Do you ever have to track that person down when you are running low?

Let me stop you for a moment, I'm sorry. Dr. Cotton, with regard to that k562 lane, could you point that out again.

Right here, (Indicating).

All right. And could you explain just briefly again, what is the purpose of that sample?

That sample is simply another control DNA whose pattern, now that we have run it a number of times, is recognizable. We do not in our lab have standard sizes for this lane yet. We still are accumulating numbers for that. So we are not using it, umm, in exactly the same way we are using the TDS, because we do have standard sizes for that, so we are accumulating those standard sizes, but the pattern does look as it is supposed to.

Now, as to the number of these samples, where it is the lambda, the 1 KB, the TDS, referring to the first three lanes on the left, and then the K5--and the additional 1 KB's in the middle and off to the right, as well as the k562, if something goes wrong or doesn't appear correct when you are reading this result, does that kind of turn on a light in your head or what?

It alerts you to the fact that something might be wrong. Now, it could be that something is just wrong with that standard sample and that you demonstrate that, but it also tells you something could be wrong with the standard samples and the gel run in that particular case, which then would affect all the samples. So if anything doesn't look right, you would go in and figure out what was the problem, did it affect all the samples in that gel run or is it specific to that particular standard? If possible, even if it was just specific to the standard, you could go back and rerun them. Sometimes if we have a problem with the standard and we can't rerun the evidence--and actually I don't want to be confusing. I'm using "standard" essentially two ways. Usually if it is a known sample, I will try to call it a known sample from a known person. If it is one of our standard markers or the TDS, I will try to remember to refer to it as a standard sample in the lab. If we had problems with a standard sample, such as TDS, and we couldn't rerun the evidence, we might rerun the standard and the known samples from that case to make sure that everything was reproducible. So a problem with a standard doesn't mean you have to dismiss all of the results, but it does mean that you better look at them closely and make sure that everything is okay.

Okay. Referring you, if I can, and let's start with this first lane that is labeled lambda, why is it the bands that are shown there seem to be smaller than the band in the next lane over, the 1 KB? Is "smaller" the right word or not?

Are you--okay. You are asking me why are these bands narrower from top to bottom than these bands in the 1 KB lane?

Yes.

There are two things that can affect that. One is that there may be more DNA in the 1 KB lane, more total DNA in that lane, than in the lane that has the lambda DNA. We are loading standard amounts. I think that the amount of lambda that is loaded may be less, but I would have to go into the protocol to confirm that. The other thing is that when you look at this kind of difference, whenever you are looking at a larger band versus a smaller band, or a dark band versus a light band, there are many things that can affect that. It--it is a technical enough procedure that a single explanation may not be the only contributing thing to making something darker or lighter. In this case the answer to your question is there are two possible contributing things: One is that there is less DNA in the lambda lane than the 1 KB lane, and the other would be that the amount of p32 in the probe for the 1 KB was more than the amount of p32 in the probe for the lambda and that is something that can also affect how dark or light a particular band is.

As far as this difference in the darkness and lightness and the narrowness of the bands, does that make any difference in your ability to interpret results?

On this film in this example it wouldn't make any difference at all. It certainly can make a difference. Bands can be very light. Bands can be very dark and close together, such that you can't make an absolute distinction of whether there is a single band or two very close together, so it can make a difference, but it is not really making a difference on these markers. Let me give you a better example. Let's come over here, (Indicating). You can see that this band in the k562 lane--can I make that stay there? No. What am I doing wrong? How do I make it stay there?

By pushing the button.

Oh, right, the button. There we go. Okay. That band, (Indicating), is more intense than the two bands above it, and the band below it. Without going back and looking, I can't remember, but it could be that for the cocktail there are actually two bands there, one identified by one probe and one identified by another, so that you see basically overlapping bands and that is a--I'm just making this up as an example--that is another reason why a band might be darker than the bands above it or the bands below it.

How do you answer that question or do you answer that question that you have just asked in the course of your further testing?

Yes, because as you go through and do each individual probe by itself, you can then in doing that--let's see if we can undo this arrow. Let's--this is--okay. Let's say we went and did each individual probe by itself and we identified that this band and this band, (Indicating), came from the first probe. And then let's say we went back and get another band--I mean, sorry--another probe and we identified that this band and this one over here, (Indicating), came from probe no. 2. And you could go back and do another hybridization and we might see that on the third probe that identified this band and this one, (Indicating), and go back then and do the fourth probe that is part of the group and perhaps the fourth probe would again identify this band and this remaining band, (Indicating). So in the process of doing them each individually, you can define the pattern that you see, which bands came from which genetic location. The cocktail is great for telling people apart. You can see here that clearly Mr. Simpson, Miss Brown, Mr. Goldman all have different overall patterns. To establish more information than that, it is desirable to go back and necessary to go back and do each probe individually. Now, we didn't do that on this film, because the evidence lane doesn't have a banding pattern, so I can't show you that, but on the other film we did do that.

All right. We will return actually to both of those things, the actual evidence on this x-ray, as well as the fact that you did these probings individually on other x-rays as well or other x-rays in addition to that. One more question generally about this x-ray itself. There appears to be some darkening between the bands, for instance, on the third lane labeled TDS; is that correct?

Over here you are talking about, (Indicating)?

Yes.

You are talking about this background in here, (Indicating)?

As well as in, for instance, the sample that is labeled "n. Brown" at the top as well?

Yes, here. All of this, (Indicating).

And to some lesser extent in what looks like two other of the lanes or perhaps three as well; is that right?

Yes.

What is that?

That is the background that you see as DNA becomes degraded. The more degraded the sample is, the darker this general background becomes, and the longer the exposure, that is, the longer the x-ray film has laid over the membrane to expose, the darker this background will become.

Does that affect your ability to interpret results, the fact of this background?

I have certainly seen DNA patterns where the degradation was so substantial that it basically obliterated your ability to see any bands. For the most part, even if there is degradation, you can still see where the bands are, because they are superimposed over it and they are still darker than the background. It can affect your ability to read it. It doesn't all the time.

Does it affect the accuracy of the results themselves?

As long as it doesn't affect the ability of the computer imaging system to choose where that band is or your ability to assess that the computer imaging has chosen the band position correctly, then it generally won't affect the results, but if it is dark enough, it will.

Can it, for instance, turn one type into looking like a different type?

No, it doesn't do that.

So in other words, this part of the of the testing process doesn't affect your ability to accurately type samples?

Does that question make sense?

No.

Okay. I will withdraw it then. Thank you.

Now, as far as--the next area I would like to ask you about, Dr. Cotton, is you described briefly how it can be seen that the sample from the three known individuals, Mr. Simpson, Nicole Brown and Ronald Goldman, have different overall patterns. Can you describe that and show that for us, please?

Okay. The--let me just take a look at the light box.

Remember that we are making the assessment of a pattern by looking at the position of each of the bands as they are distributed from the top to the bottom, so let's just say we have--we have these three people here. Mr. Simpson has three bands that are close together that are almost near the top of the 1 KB ladder.

Let me stop you for just a moment, Dr. Cotton. Perhaps you can clear all of those arrows that you have already done off to the right.

Okay. There we go.

Thank you.

He has three additional bands lower down, and although you can't see it very well on this screen, there is an additional band down here, (Indicating), which I had to check on the light box to make sure that I remembered that there was one down there. This isn't--this isn't necessarily the optimal way of viewing these, and in the laboratory you would just look at it on the light box and make your decisions based on how it looked laid on the light box like I have it over at the table. So if you make a comparison, we will just compare Mr. Simpson's pattern to the TDS pattern, the TDS pattern also has some close groupings of bands, but they are not in the same position as the groupings that Mr. Simpson has. This lower grouping down here, (Indicating), there is no bands at all, so this pattern is clearly different from the TDS pattern.

Let me stop you for a moment, Dr. Cotton. With respect to Mr. Simpson's DNA we see what appear to be a grouping of three bands and then a little lower down another grouping of three bands and then you described further on, almost all the way down this x-ray as we could see it, then a light band. What can you tell us about why that band would be lighter?

We know from many, many--let me just--let me put an arrow right here where I think that light band is, and actually the TDS pattern also has a light band, and that one is right here, (Indicating), in a slightly different position. We know from understanding the gel and understanding how the radioactivity or the probe DNA that is radioactive binds, that in this system and some other systems, but I will just refer to the Cellmark system, when a band is very small it tends to be lighter. You can see that in the TDS control and you can see that in Mr. Simpson's pattern. One of the reasons for that is that the total number of repeats in that small band, remember, the length of the band is defined by how long that repeating sequence is, and the probe is going to bind to that repeating sequence. The total number of repeats available for a probe to bind in a very small band is substantially fewer than a band that is more sizable. That is just another example of a technical reason why you might see bands that are different--differing in intensity.

Incidentally, does Mr. Goldman also have a similar band in that range?

Yes, he does.

Perhaps you could point that out.

That would be right there, (Indicating).

Now, with respect to those lighter bands, how do they affect your ability to type results accurately?

The largest problem that you might have is that you may have two samples that have the same pattern, a known and an evidence, and if you have less DNA for--let's say you have less DNA in the evidence than you do in the known, you can see that if--if you get--if it gets very much lighter, that is those lower bands, if they got very much lighter, you wouldn't be able to see them. So it does happen occasionally that you might be missing a lower band such that your evidence, say, had eight--sorry. Let's say your known had eight and the eighth one was down in this region of the gel, (Indicating), or maybe even in this region, (Indicating), and the evidence only had seven and didn't have one in that region. And that leaves you with two explanations. Either the DNA has--in the evidence actually may have all the bands but you can't see one, or the DNA in the evidence is not--could not be from the same person as the DNA in the known. And you would have to then make some decision about interpretation of that seven--of those seven bands as compared to those eight bands.

Now, Dr. Cotton, with respect to these three samples, whether it is Mr. Simpson's, Nicole Brown Simpson's or Ron Goldman's, those are known samples? In other words, to your knowledge it was identified where they came from?

Yes.

In other words, they came from known individuals?

Yes.

Now, I also believe I interrupted you when you were describing the differences in the overall patterns of the three individuals.

Or had you finished?

Well, you could do more. I don't--

Next question.

Yes, definitely, your Honor.

Now, I would like to turn your attention, Dr. Cotton, if I can, to the sample or the lane which looks like it is the fifth one from the left that is labeled "no. 56 print."

Okay.

With regard to that sample--and again that stain was put through this RFLP typing possess, correct?

Yes, it was.

What kind of results do you see from that particular sample?

What does that mean?

All right. Dr. Cotton, I'm going to ask you several questions about that particular sample, but I believe you could answer those from the witness stand, if that would be more comfortable.

Okay.

And your Honor, at this time I would like to place on the projector screen the actual photograph of this particular evidence item.

All right. Is that available?

Yes, I believe so.

This will be 258 or have we numbered this yet?

This I believe is already marked as People's 45-J.

45-J.

Now, Dr. Cotton, with respect to item 56 before you actually had this sample tested using the RFLP process--and I'm going to clear the arrows--do you go through a particular step with a sample to try to determine if there is human--I'm sorry--if there is DNA present and if so approximately how much?

Yes.

How do you do that?

After the DNA extraction and before you do the next step, which is the restriction cutting of the DNA, you take a very small portion of your DNA and run it on a very small gel, it is about oh, three inches by four inches, two inches by three inches, something like that. And what that allows you to do is determine whether the DNA is in pretty good condition or whether it is degraded or somewhere in between, and it allows you to make a rough estimation of how much you have. And it doesn't tell you whether it is a mixture and it doesn't tell you whether it is human; it just tells you whether you have some DNA there.

And did you perform that particular step with regard to this item no. 56?

Yes, we did.

What did it tell you?

I'm sorry, your Honor. I would object and just ask for the instruction.

You haven't established the connection of 56 to this item yet, so I will take that as an objection subject to a motion to strike.

Right.

Proceed.

Could we approach, your Honor?

Proceed.

All right.

With regard to this particular item that was provided to you, item no. 56, what were the results of this test to determine how much DNA was present?

Again objection for the same reason.

Same ruling.

All right.

Proceed.

When we ran the DNA obtained from item 56 on the mini gel there was clearly DNA there and it appeared to be in good condition.

What does that tell you about your ability to then type that DNA?

Right then it doesn't tell you anything.

Okay. Does the result of that test affect what further steps you take in terms of typing that sample?

Well, it certainly can. If you have very little DNA or it is very degraded, at that juncture then you might decide that it is not of sufficient quantity and quality for RFLP and that you should then go on and do PCR.

So in other words, you use this step as sort of a guide as to which typing approach, RFLP or PCR, would be the more likely to produce results that give you information?

That's right.

With regard to this particular item, did you make a determination of which approach then to try RFLP or PCR?

We made a determination to try RFLP and we knew that we had enough sample left over to do PCR, so we went ahead clearly from the film that we shouldn't have--I mean shouldn't have--it doesn't matter that we did it, but it didn't give us any result.

Did the fact that it produced no RFLP result, was that something you expected or was that a surprise of any sort?

Well, that was sort of a surprise. Umm, what I haven't mentioned, there is also a test you can do to determine whether you have human DNA, so you could do both your mini gel and a test to determine whether you have human DNA and we routinely do that for PCR samples. We did not do it for this sample before the RFLP. We did do it later on, so because we hadn't done it, we didn't know that that wasn't human DNA and we did proceed with an RFLP analysis.

Now, you described earlier the role that bacteria can play in terms of degrading human DNA; is that right?

Yes.

With regard to this particular instance, to what extent can you offer an opinion about the possible role of bacteria?

If there was originally human DNA present in that sample, it is substantially degraded and not able to give any--it is so degraded that no RFLP pattern could be obtained.

And to what extent, if any, does--I'm sorry, does bacteria play a role in that or could play a role in that?

Well, it can play a role in that. If a sample is deposited on a surface that has a lot of bacteria, then the bacteria may participate in the degradation of that DNA. Bacteria contain many enzymes, many proteins that will break up DNA in a random manner, and therefore, when bacteria is present DNA degradation occurs.

Now, did you subject this same material provided as item no. 56 to you to PCR typing?

Yes, we did.

Did you obtain results?

I believe we did.

Can you verify that from the materials that you have?

Sure.

Yes, we did obtain PCR results from that sample.

Do those results then allow you to make any conclusion about whether or not there is human DNA in this sample?

Yes, they do.

Why is that?

The PCR test also is pretty much considered to be human specific. That is, it will recognize human DNA and you might be able to type a primate, like a chimpanzee or a gorilla, but you can't type other animals, so the fact that we got a PCR type from that sample is a very good indication that there was human DNA present.

So then is it the case, with respect to your RFLP typing that produced no result, that doesn't mean there was no human DNA in that sample?

That's right. What it means is that the DNA was so degraded that it was incompatible with giving a result.

As far as bacteria are concerned, do bacteria result in changing the type of a sample, for instance, if bacteria was present in item no. 56?

All right. Now, what I would like to do is shift your attention, Dr. Cotton, to a second series of x-rays that you created after testing other evidence. First of all, you have, do you not, with you, x-rays of other RFLP tests in this case other than 56?

Yes.

Incidentally, with regard to item no. 56, and that first auto--x-ray, I'm sorry, that you have been showing on the board, did you then, in the case of that sample and those three knowns, go through this process of doing one probe at a time creating additional x-rays?

Not with that film.

Why?

Because there was--since there was no evidence--since there was no information obtained from the evidence, we didn't go through the process of doing each probe by itself, because there is just no DNA there from the evidence, so there is no--nothing to be gained by doing that.

So there is no reason to go further with regard to that sample?

That's right.

Now, did you also receive--well, let me rephrase. When you conducted this RFLP typing, again did you do it on other samples in addition to 56?

Yes, we did.

Did those include samples that you actually obtained RFLP typing results for?

Yes.

In particular, did you test on one x-ray what included items no. 52?

Yes.

MR. CLARKE: Your Honor, with the Court's permission I would ask that a photograph of 52 be placed on the elmo as well. (Discussion held off the record between Deputy District Attorney and Defense counsel.)

Which is I am told exhibit 48-I.

And in particular, your Honor, with regard to the board which has been marked--I'm talking about the photo board that is on the easel currently as People's exhibit 165--in particular, the photograph labeled on the left-hand side of that board, three photos down, labeled "item no. 5."

Was that one of the items tested during this RFLP typing possess, Dr. Cotton?

Yes.

On this particular test or during this test did you also test any other items in this case?

Yes.

What were those items?

Item no. 78 and item no. 12.

All right. What I think we will do is take them one at a time. Do you have with you the first x-ray in this testing process for those items you have just described?

Yes.

Would that be what you've called the cocktail x-ray or cocktail autorad?

Yes, but I'm going to have to find it.

Dr. Cotton, we may have the original.

I was hoping you did, because I wasn't seeing it in this group.

Incidentally, is that the original of that particular x-ray?

It sure is.

How are you able to tell that is an original instead of a copy?

Sometimes the copies are a different color, but these recent copies are not, and they are so close to the originals that what I'm doing is feeling for the labels that are stuck onto the originals and I can feel that this has the labels on it and so I can really quickly say this isn't the copy.

All right. With respect to this particular cocktail x-ray, I would ask that that be marked as People's next in order, your Honor.

People's 258.

Did we premark this already?

I'm sorry. That has been marked, your Honor. That is 257-A.

257-A.

I apologize.

Now, Dr. Cotton, with respect to the samples that were tested on this particular x-ray, would it again assist you to use the overhead projector as well as the pointing machine?

Sure.

All right.

All right. Dr. Cotton, if you can, can you describe for us what is shown on this particular x-ray? What are the samples?

Do you want me to list the controls as well?

If you can just describe them briefly and answer whether or not they are the same control or the same types of controls used on the earlier x-ray?

The film is laid out in terms of where the samples were loaded on the gel in a similar manner to the one that you saw previously so that we have marker lanes on the left, two marker lanes on the right. They are the same markers as before. All the films have the same markers, the lambda and the 1 KB. The reason that you can actually see the markers is that a probe is also added that identifies the markers, because the markers are not from human DNA, and if you didn't add a probe specifically for them, you wouldn't be able to see them. There is also an additional marker lane in the center, another 1 KB ladder. There is a TDS standard over here, (Indicating). This standard shows some degradation. And again what--as you view it on the light box, as opposed to viewing it on this screen, it is not this dark. The same is true with some of these lanes over here. When you look at it on the light box it is a little bit easier. There is also a k562 lane on this film that is shown right here, (Indicating). There--the three known samples are here, (Indicating): Simpson, Brown and Goldman. The three evidence samples are loaded over here, no. 52, no. 78 and no. 12.

Now, with regard to, and you have identified or described the fact that the three known samples are towards the right of that x-ray; is that right?

That's right.

And they have created certain banding patterns; is that correct?

That's right.

Now, with regard to those lanes--and let's look at, for instance, what is labeled Nicole or N. Brown, that lane appears to be dark. Can you describe what causes that?

This sample has a considerable amount of degradation in it. That was seen as early on as the mini gel when we looked to see how much DNA we got from that sample. You can see on the mini gel that that DNA is degraded. The same is actually true for the sample from Mr. Goldman, although on this particular film the sample from Nicole Brown looks slightly more degraded than the sample from Mr. Goldman. All of the samples of the known on this film and the TDS and the k562 appear to be rather dark, and they are, and the reason is that this was a long exposure because one of the evidence lanes didn't have very much DNA in it.

Now, which lane was that?

The lane that doesn't have very much DNA is the lane where we have sample, no. 52, and you can see how much lighter this banding pattern is as opposed to the others, (Indicating). Now, among all the various things that can determine whether something is light or something is dark, the overall most common reason is how much DNA is there. And we also know quantitatively--well, in estimating from the mini gel that there wasn't a lot of DNA in that sample.

Does the fact that some of these lanes are darker prevent you from being able to interpret the results?

If we had just this film, you would--you could interpret it, but I would rather see all the films in series and interpret them altogether, than just use this one. The bioimage was used on this film, the sizes were done from this film, but anytime that you have a whole set of data, you would like to look at the entire set before you come to a conclusion, not just look at a single film.

Now, from looking at these--from looking at these particular samples--and let me focus your attention on what appear to be the three evidence items, no. 52, the Bundy walkway, no. 78, Mr. Goldman's boot and no. 12, the Rockingham foyer--what can you tell us about the relative amounts of DNA in those three items from this x-ray?

From this film, no. 12, would have the most in comparison to those three. No. 78 would have sort of a middle amount and no. 52 would have the smallest amount of DNA.

So from left to right on those three items, basically the DNA goes up in terms of its amount?

Yes.

Now, as far as once you obtain this particular x-ray, was it in fact examined for any results or interpretations that could be made?

Yes.

What can you--

It was.

What can you tell us about any conclusions or opinions you reached from this particular film?

From this particular film you can--let's look at each piece of evidence individually. Item 52 has three bands close to the top, another grouping of three bands, and a single band down here, (Indicating), and that pattern is consistent and looks to be the same as the pattern from Mr. Simpson which also has a group of three, another group of three and a single band down at the bottom. And because of--sorry.

Go ahead, I'm sorry.

Because it also has the same pattern, let's go on to sample 12. It also has a group of three bands, another group of three bands, and a single band way down at the bottom, so the DNA banding pattern from item 52 and item 12 are--I'm now speaking as if I was making an initial interpretation from this film--they are certainly consistent with the pattern from Mr. Simpson. Later on, after doing some measurement, you would make a determination that--where you would say the patterns match or they do not match, but at this point they are visibly the same.

All right. Dr. Cotton, what I'm going to ask you to do is without wearing out your thumb, if you are using that to place the arrows, could you place the arrows on each the bands you see in the Bundy walkway lane, item no. 52.

Do you want each band or shall we do the two groups of three?

Whichever is easier, as long as it will show the relative positions.

It is probably clearer to--

I will just--so we don't have too many arrows up here, I will just point to the middle band in this group of three and the middle band in this group of three, just indicating that I have a group of three and a single band down here at the bottom, (Indicating). And I will make the same designation for the--did you want me--I'm sorry.

That's fine.

Did you want me to go on to no. 12?

Yes, if you would.

I will make the same designation for the two groups of three bands in item no. 12 and the single band down towards the bottom, and the group of three from the known sample from Mr. Simpson, the second group of three, and the single band down at the bottom, (Indicating).

All right. Your Honor, then with the Court's permission, I would ask that this particular x-ray film that has these arrows on it be printed and marked as a People's exhibit.

Yes. Do you want to make that a separate exhibit or do you want to make it a sub exhibit under 257?

The only hesitation I have as a sub exhibit is that there are already sub exhibits to 257, but that may still be appropriate. 257-A(1).

A-1.

All right. Would this be an appropriate point?

Yes.

Ladies and gentlemen, we are going to take our recess for the morning session. Please remember all of my admonitions to you. Do not discuss this case amongst yourselves, don't form any opinions about the case, do not allow anybody to communicate with you, do not conduct any deliberations until the matter has been submitted to you. We will stand in recess until one o'clock. All right. Dr. Cotton, you may step down.