Kaye
Kaye
DIRECT EXAMINATION BY MR. ORENSTEIN:
Q. Good morning, Mr. Cadigan.
A. Good morning, sir.
Q. Where are you employed, please.
A. I am a special agent of the Federal Bureau of Investigation, and I'm assigned to the Firearms and Tool Marks Unit of the FBI Laboratory in Washington, D.C.
Q. What are your responsibilities there?
A. As a member of that unit, I have three areas of responsibility. I do serial number restoration examinations, I do firearms identifications, and I also do tool mark examinations.
Q. How long have you been doing tool mark examinations?
A. For 20 years.
Q. Now, can you tell the ladies and gentlemen of the jury basically speaking what a tool mark examination is.
A. Tool mark examination deals with the comparison of marks that are left at the scene of a crime with a particular tool in order to determine whether or not that particular tool made that mark. For instance, in a burglary in which a screwdriver is used to pry open the window of a residence, tool mark identification or tool mark examination would look at the marks on the window sill and compare them to marks made by the screwdriver to determine whether or not that screwdriver made the marks on that window sill.
Q. Now, when you do that kind of examination, are there different types of marks that can be examined?
A. Yes, sir.
Q. Can you describe the different types of marks?
A. Well, basically, there are two different types of marks. One would be called a
compression or impression, where the screwdriver blade would be pushed in and then pressed
down. That would leave a depression or impression on the window sill.
The second type or general type of tool mark would be called a striation or scratch, and
that would be from the blade of the screwdriver dragging across the window sill and
leaving scratches on the surface.
Q. Now, did you conduct any tool mark comparison in this case?
A. Yes, I did.
Q. And did it involve a padlock and a drill bit?
A. Yes, it did. * * *
Q. Are there -- what kind of marks does a spinning drill bit leave? * * *
A. A drill bit would leave striations left by the cutting of the blade and the tip of the drill bit. * * *
Q. Now, you told us earlier that you did tool mark analysis in this case. Can you in general terms first explain to the jury what it is that you did?
A. Yes. I received a padlock that had some drill-bit impressions in it, and I was given two drill bits; and the request was to determine whether or not either one of the two drill bits made the impressions contained on the padlock. * * *
Q. Now that the photograph is before the jury, can you describe the striations that you looked at on the test impression?
A. Yes. In that particular photograph which shows the drill-bit impression I made with Government's Exhibit 151B, the comparisons I did looked at these striations that are all along here that are going in a circular fashion and also the striation marks that are here that are also going in a circular fashion and comparing those with the ones that were found in the lock cylinder.
Q. Now, when you made Exhibit 244, which is the photograph in this item, was that on a flat surface?
A. This was, yes, sir.
Q. Now, once you had made these photographs -- and these are just for illustrative purposes -- did you compare the padlock and the test impression?
A. Yes, sir, I did.
Q. How did you go about comparing them?
A. I placed the lock cylinder under the comparison microscope and looked at the tool marks that were present in that lock cylinder and compared them to the marks that I had produced with Government's Exhibit 151B to determine whether or not that drill bit made the impressions contained on that lock cylinder.
MR. TIGAR: Your Honor, may that answer be stricken?
THE COURT: Yes. It is stricken.
MR. ORENSTEIN: Your Honor, may I approach for a moment?
THE COURT: No. * * *
Q. Now, if we open up both sides of this exhibit, do we see what you saw when you looked through the comparison microscope?
A. You see a portion of it, yes, sir.
Q. And is that -- does that illustrate what you saw when you looked through the comparison microscope?
A. Yes, sir.
Q. Now, do you see any areas of similarity from one side to the other?
A. Yes, sir, I do.
Q. And can you point out the similarities that you saw?
A. Certainly. As we can see from the striations that are left by the drill bit -- continue over onto the lock cylinder in these areas. And those are tool marks that are contained on the lock cylinder again on the left side and the drill-bit impression on the right side.
Q. So these striations on one side from the test impression you see is also reflected on the other side in the impression in the lock; is that correct?
A. Yes, sir.
MR. ORENSTEIN: Thank you, Agent Cadigan.
Your Honor, I have nothing further on direct.
THE COURT: All right. Mr. Tigar?
MR. TIGAR: Your Honor, we would respectfully request -- I made a motion to strike most inartfully. Would the Court instruct the jury as to the significance of that?
THE COURT: Well, what the motion to strike was about was the witness giving an opinion with respect to comparison, and I struck that because what is permitted here is to show what he saw through the microscope and the comparison microscope and then with his experience and training the similarities that he pointed out.
MR. TIGAR: Thank you, your Honor.
CROSS-EXAMINATION BY MR. TIGAR: * * *
Q. So they have tolerances in the manufacture that are designed to make the drills identical at least with respect to size. Is that correct?
A. That is correct.
Q. Now, in addition to making them identical with respect to size, the manufacture of drill bits in today's world is automated, isn't it?
A. Yes, sir.
Q. Okay. Now, in this machining process, is it your belief that every drill bit that comes off the line is unique when it leaves the factory?
A. In the production, once it's sharpened. * * *
Q. All right. And the -- now, when you say that it's unique, you're taking account of the fact that, what, every time a cutting tool cuts something, it changes; right?
A. It's based on the fact that as the tool is sharpened, it is sharpened using a wheel that presents in a random-pattern grit that removes metal; and each time that wheel turns, grit falls off, pieces of metal fall off and leave a unique pattern on the tip of that screwdriver blade or drill bit.
Q. Talking about drill bits?
A. Drill bit. And those unique patterns on the tip of that screw -- drill bit are left when that drill bit is used on a surface.
Q. Now, we're talking about the manufacturing process, sir. We've gone a little bit beyond. When the -- let's look at the place where the pointy end of the drill is being made. Right? That pointy end makes contact with a wheel. Correct?
A. Yes, sir.
Q. All right. And the wheel is spinning very fast. Right?
A. Yes, sir.
Q. Now -- and that's the same -- if I make -- if the manufacturer makes a thousand drill bits in one day, every single one of the ends of those drill bits is going to come in contact with that same wheel; correct?
A. Yes.
Q. All right. And if you were at the factory and you took that wheel, would you be able -- at the end of a day's run, would you be able to identify the 1,000 drill bits that were made that day using that wheel?
A. I don't understand that question.
Q. Well, you testified, sir, that in our hypothetical example a thousand drill bits are going to be made by a manufacturer. Correct? We understand that. That's our hypothetical?
A. Yes, sir.
Q. Let's assume they're a thousand quarter-inch drill bits.
A. Yes, sir.
Q. And you told us that the way those drill bits get made is that the -- what's going to become the pointy end comes into contact with a grinding wheel sometime during the production process. Correct?
A. Yes, sir.
Q. All right. Now, if you were able at the end of the production day to take that grinding wheel and look at it under your microscope, would you be able to correlate that to the thousand drill bits that were manufactured that day?
A. Would I be able to match the grinding wheel?
Q. Yes.
A. With the drill bits?
Q. Yes, with the drill bits.
A. I don't think so.
Q. All right. Well, a grinding wheel is a cutting tool, isn't it?
A. Yes, sir.
Q. And a drill bit is a thing that receives an impression from a cutting tool. Correct?
A. Yes, sir.
Q. And it's your testimony that in that instance you would not be able to make a match between the thing that cuts and the thing that's being cut. Right?
A. Well, in the case --
Q. You can explain in a minute, but I need you to answer my question. Is it your testimony that you would not in that case be able to make a match between the thing that cuts and the thing that's being cut? Yea, or nay?
A. It's sharpened, as opposed to being cut, but there wouldn't be any pattern on the grinding wheel that you could compare to the drill bit.
Q. Okay. And you say, "sharpened, as opposed to being cut." The -- a grinding wheel has little bits or flecks of diamond or emery or something like that. Right?
A. Yes, sir.
Q. So when we say "grind," all we mean is cut -- that's a series of little cuts rendered by the little pieces of grit that are on the wheel; right?
A. "Sharpened" is a more accurate term for me.
Q. All right. Now, in this manufacturing process that we're talking about, you said you collected, you know, 150 or so drills. Right? Now, is -- have you read any of the literature about drill-bit comparison?
A. Yes, sir.
Q. Okay. Have you read a book called Modern Scientific Evidence, The Law and Science of Expert Testimony?
A. I don't know that I have.
MR. TIGAR: May I display it to the witness, your Honor?
THE COURT: Yes.
BY MR. TIGAR:
Q. Do you know this book?
A. No, sir.
Q. Have you read any work on firearms and tool marks by Alfred Biasotti and John Murdock?
A. Yes, sir.
Q. Do you recognize Alfred Biasotti and John Murdock as experts in the field of tool mark identification?
A. They have written several articles in the field, yes, sir.
Q. I didn't ask that, sir. Do you recognize them as experts in the field of tool mark identification?
A. I recognize them as people that have expertise.
Q. Now, are they members of this AFTE? Do you know?
A. Mr. Biasotti was a member of it and Mr. Murdock is. * * *
REDIRECT EXAMINATION BY MR. ORENSTEIN: * * *
Q. Now, on cross -- on cross-examination on Friday, the defense attorney asked if it's your belief that every drill bit that comes off the line in the manufacturing process is unique when it leaves the factory. Do you recall that question?
A. Yes, I do.
Q. Could you explain how the manufacturing process produces unique drill bits.
A. Certainly. As each of the drill bits is pressed against the grinding wheel --
MR. TIGAR: Object to this, your Honor.
THE COURT: What's the objection?
MR. TIGAR: No foundation for his opinion.
THE COURT: Overruled.
THE WITNESS: As each of the drill bits is placed onto a particular machine, it's then placed up against a grinding wheel. And the purpose of the grinding wheel is to sharpen the tip of the drill bit in order so that it will perform its function; that is, cut and remove metal. That wheel has random particles on it that are presented to each of the tips, the tips of the drill bit, that are to be sharpened in a random fashion, and that's why from the first to the 1,000th drill bit produced on a particular grinding machine, they will be different, because each time that wheel turns and it scrapes against the drill bit, particles drop off; and particles of the metal, of the drill bit, are sharpened and thus produce a unique tip for each one that's produced.
BY MR. ORENSTEIN:
Q. Now -- excuse me -- is the grinding wheel that's used in that process, is that larger than the surface of the drill bit that it's cutting?
A. Yes, sir.
Q. So you could have one drill bit grinded (sic) against one part of a wheel and the next drill bit is ground against a different part of the same wheel?
A. Yes. And normal function is that the wheel is indexed, which means it's moved for each drill bit. The first drill bit is sharpened. The first portion of the drill bit is sharpened, it comes out, the drill bit rotates, it goes back in, and as it goes back in, it moves just slightly so it hits a different part of the wheel so a groove is not cut into the grinding wheel so it wears the grinding wheel evenly. So it hits a different part of the grinding wheel each time.
Q. Now, is it generally the case that one drill bit, which has, as you testified, two different surfaces -- will those two surfaces be cut against the same grinding wheel?
A. Yes, sir.
Q. And obviously it's the same grinding wheel, so it would produce, one would expect, similar if not the same cuts?
A. It would be similar.
Q. But even with that similarity, again, looking at Government Exhibit 1843, which is on your screen, does that show the difference in striations that are left even when the same wheel cuts one drill bit at two different times?
A. Yes, sir. * * *
RECROSS-EXAMINATION BY MR. TIGAR: * * *
Q. You talked about this business of manufacturing drill bits. I want to ask you some more about that since it's been gone into. In 1995, did the FBI under your direction begin a study of whether or not a drill-bit mark made in a particular item could be identified as unique?
MR. ORENSTEIN: Object as beyond the scope of redirect.
THE COURT: Overruled.
THE WITNESS: In probably late 1996, we started to accumulate drill bits to study them to perhaps provide a more statistical base for the examination. But the purpose of the study --
BY MR. TIGAR:
Q. Thank you, sir. You've answered the question. You started to make a study. * * *
Q. Well, the study was in this case named "Drill Fire," wasn't it?
A. It was in this case named "Drill Fire." * * *
Q. And in connection with this operation Drill Fire or this study, someone looked at the possibility of getting Microsoft Mathematica; correct?
A. I think so.
Q. And someone also looked at the possibility of making some kind of standard statistical analysis; correct, sir?
A. It's my understanding that there was -- we were looking at what might occur as far as a statistical study.
Q. Right. Because in order to know whether or not something is truly unique, or a little bit unique, or could have happened a number of times, we can apply to the insights of statistics in order to evaluate that; right?
MR. ORENSTEIN: Objection. Scope and relevance.
THE COURT: Overruled.
THE WITNESS: I don't think that the statistical study would prove it. Certainly the -- utilizing the computer would aid in establishing the criteria for such an identification, but it doesn't -- you cannot make an identification based on statistics.
BY MR. TIGAR:
Q. To take an example from another field, there's no known instance of two people having the same fingerprints; right?
A. That is correct.
Q. And millions and millions and millions of fingerprints have been studied; correct?
A. That is correct.
Q. So now you're confident in knowing because the science has been done that a fingerprint is unique; correct?
A. Yes, sir.
Q. Right. You were going to do a study to see if you could analyze statistically drill bits; right?
A. We were going to look at drill bits.
Q. Right. And in that connection, someone was going to do a Poisson distribution; right?
A. I don't know that they were going to do that as part of the study. It was just one of the things that the person that was making those notes was thinking about.
Q. All right. And what is a Poisson distribution?
A. I have no idea.
Q. All right. Do you know that a Poisson distribution is something named after a scientist who made a mathematical way to look at evidence as how often things happen and whether they're random or not?
MR. ORENSTEIN: Objection.
THE COURT: Sustained.
BY MR. TIGAR:
Q. You don't know what it's about, okay. Was this study ever completed?
A. No, sir.
Q. Was -- are there work papers from this study?
A. Well, there are -- there's still work to be done in it. The drill-bit impressions need to be examined by me, and paperwork needs to be -- final paper needs to be written, but, no, it's not done yet. * * *
THE COURT: Next witness, please.
MR. MACKEY: Your Honor, the United States will call George Krivosta. Ms. Wilkinson will examine. * * *
DIRECT EXAMINATION BY MS. WILKINSON:
Q. Good morning, Mr. Krivosta.
A. Good morning. * * *
Q. Tell the jury where you work, Mr. Krivosta.
A. I'm employed by the Suffolk County Crime Laboratory, which is part of the medical examiner's office in Suffolk County, which is under the jurisdiction of the Health Department. * * *
Q. And what do you do at the crime -- Suffolk County Crime Laboratory?
A. I'm the supervising forensic scientist in charge of the Firearms Unit at the crime laboratory.
Q. And what type of examinations do you do in the Firearms Unit?
A. Firearms and tool mark examinations.
Q. Now, do you have any connection with the FBI Laboratory?
A. I do not.
Q. Do you also do independent examinations?
A. Yes, I do.
Q. Does that mean when you do an independent examination that you're not doing it for the Suffolk County Crime Lab?
A. That is correct.
Q. And were you asked by the Government in this case to conduct just such an examination?
A. Yes, I was.
Q. And have you worked in the past for both prosecution and defense?
A. Yes, I have. * * *
Q. Is there anything about examining the tool marks from a spinning drill bit that makes the examination easier?
A. The surface of the tool is a ground surface.
Q. Meaning -- which surface is the ground surface?
A. The cutting edge of the drill is ground. And ground -- grinding is a type of machining procedure that leaves very -- what we refer to as accidental marks, the possibility of carryover. "Carryover" means that something can be manufactured and something else manufactured immediately thereafter could have the same type of markings on it. Drilling -- or I should say grinding is a type of machining process where that cannot take place. The cutting away of the metal is done by the very little abrasive bits of material on the -- on the wheel. They're harder than the tool steel. They tend to make small scratches, but they're turning. They immediately -- they take a little metal off and they come away, and something -- a different one in a different place comes along. The possibility of getting the exact same structure becomes rather infinitesimal. So when we talk about looking at the striations in a reproducible pattern, they would have to be there either -- the only way they could be there other than from having the same tool would be by pure chance. * * *
MR. TIGAR: At some point, I'd like to voir dire.
THE COURT: All right. Now would be appropriate.
MS. WILKINSON: This would probably be the best time.
THE COURT: All right.
MS. WILKINSON: Your Honor, may I just have a clarification on exactly what issue Mr. Tigar is voir diring on?
THE COURT: I assume it is with respect to expertise.
MR. TIGAR: Yes, your Honor.
MS. WILKINSON: Okay.
VOIR DIRE EXAMINATION BY MR. TIGAR: * * *
Q. Okay. Now, are you aware of any studies showing the statistical probability that two impressions made by two different drill bits will in fact be different?
A. There was a paper published by Joe Reitz of the Baltimore Police Department in 1975 involving a homicide case. He also took the work of -- I believe it was Art Parthalow, or something like that, from Chicago, and used his assistance in the publication of that paper in the December --
Q. That paper --
A. -- in December of 1975 in the Association of Firearm and Tool Mark Examiners' Journal.
Q. Did that paper written some 22 years ago contain a statistical analysis of the probabilities involved in comparing different tool marks?
A. It did not.
Q. So the answer to the question whether there exists any literature that would tell us the statistical probability of two different marks made by two different drills being either the same or different is that there is no such study that has been done; is that correct?
A. There are several publications of statistical study discussing ground surfaces, and --
Q. Excuse me, sir. I'm talking about spinning drill bits. Is the answer to my question that no such study exists?
A. Specifically to this singular tool, no. * * *
CROSS-EXAMINATION BY MR. TIGAR: * * *
Q. And with respect to the drill bit, do you know how long a period of time elapsed between the offense that was committed and the recovery of the drill bit?
A. I do not.
Q. You testified earlier that each time a tool is used, such -- well, each time a drill bit is used to cut something, there is a likelihood that the drill bit will be altered or changed in some way; is that right?
A. Yes, it can.
Q. And is that why -- is that one reason why it is significant to know the amount of time between the offense and the time that the drill bit is recovered and examined?
A. One would want to attempt to safeguard the tool to keep the tool from being changed from its condition so that the possibility of an association might be made. But, you know, going in the other direction starts approaching the mathematically improbable. To change it into something --
Q. Now, you say "the mathematically improbable." Are you referring to any study of the statistical probability involved in identifying a drill bit with a mark that the drill bit has made?
A. There were a number of studies relative to rare chance, which is what this would be talking about. To drill bits specifically as I stated before, there are none.
Q. All right.
A. But this would still be just a rare chance.
Q. So we're talking chance; right?
A. Yes.
Q. We're talking coincidence; right?
A. Yes.
Q. Now, when we're talking about coincidence, are we -- would you be concerned to know whether the lock had been dropped by somebody before you looked at it?
A. Once again, if the lock were dropped, it could change what's there. But to change it into something that we might find in the future and associate would have to be purely by rare chance.
Q. But you're saying there could be some change made in it from being dropped?
A. Yes.
Q. Do you know whether this lock was dropped between the time you looked at -- the time it was seized at a crime scene and the time you looked at it?
A. I do not know. * * *
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