3.David Cahill — Direct/Cross/Redirect
792 lines(Discussion at sidebar and out of the hearing of the jury:)
MR. WATKINS: This is Trooper Cahill where I filed a motion to --
THE COURT: Right.
MR. WATKINS: -- exclude.
The Court indicated -- kind of intended a ruling, but did allow us to go through voir dire. After considering it further, I would ask that we rely on the papers. I made two arguments: One is on a scientific basis, none of it should come in. I would still rely on that. I do not believe that there's a reason to have a protractive voir dire of this particular witness and will not object on that basis.
THE COURT: Okay. Based solely on the event mentioned in the papers then, the motion is denied. I think he's qualified to testify.
MR. MELLIN: Your Honor, based on the comment you made the other day about experts, do you not want me to ask --
THE COURT: I prefer not.
MR. MELLIN: Okay. That's fine.
THE COURT: I think it's limited because -- well, I think I expressed -- it depends on the question you ask. If it falls within their expertise, it's okay. If you think it goes beyond their expertise, your objection -- I don't like the blanket ruling.
(In open court:)
DAVID CAHILL, duly sworn
COURT CLERK: State your name, spell your last name for the record and speak into the mic.
DAVID CAHILL: David Cahill, C-A-H-I-L-L.
DIRECT EXAMINATION BY MR. MELLIN:
MR. MELLIN: Good morning, sir. I'm over here. It's a trick. Good morning.
DAVID CAHILL: Good morning.
MR. MELLIN: Sir, where are you employed?
DAVID CAHILL: I'm a lieutenant with the Massachusetts State Police.
MR. MELLIN: And how long have you been with the Massachusetts State Police?
DAVID CAHILL: Twenty-eight years.
MR. MELLIN: How do you become a lieutenant? What various ranks do you go through?
DAVID CAHILL: You start off as a trooper, take an exam for sergeant and take another exam for lieutenant.
MR. MELLIN: During your 28 years, can you briefly describe what you've been involved in?
DAVID CAHILL: The first 16 years I was a trooper assigned to patrol. In my 16th year I was then transferred to the Firearms Identification Section at the crime lab. At that time it was in Sudbury -- all of the crime lab in Sudbury. I was promoted to sergeant, and then subsequently, two years ago, I was promoted to lieutenant.
MR. MELLIN: At some point -- did you go to college?
DAVID CAHILL: Yes, I did.
MR. MELLIN: Where did you go to college?
DAVID CAHILL: I have a bachelor's degree in science, in criminal justice, from Western New England University, and a master's degree in criminal justice from the University of Massachusetts at Lowell.
MR. MELLIN: Now, you mentioned firearms identifications. What is that?
DAVID CAHILL: It's a section at the lab -- at the crime lab. What we deal with is firearms relating to crimes.
MR. MELLIN: And how do you go about determining if a firearm was involved in some shooting?
DAVID CAHILL: Most of the time -- well, there's two ways: One, we can be called to the scene of the crime, we recover all -- I would recover all evidence regarding firearms. The second one is if an agency, be it local, state or federal, recovers a firearm and they want it examined by our section, they will bring it to us and submit it to us at the lab in Maynard.
MR. MELLIN: Did you receive certain training related to firearm identification?
DAVID CAHILL: Yes, I did.
MR. MELLIN: Can you describe for us what training you have?
DAVID CAHILL: Yes. Over the first two years assigned to the section it's an apprenticeship program. You're working with qualified -- under qualified examiners. And during that two years, you're sent out to numerous training opportunities. Myself, I've been sent down to the ATF school for the NIBIN system in Largo, to the FBI Academy in Quantico, Virginia, for advanced technician firearms identification. I've also been to several in-house trainings that we've hired people to come in and train us in toolmarks and firearms. And I've also been to several weapons manufacturers: Colt, Berettas, Glock, Smith & Wesson. And during those armorers' courses, usually you learn how they make and maintain their firearms. I mean, a couple of them, like Beretta -- not Beretta -- on Colt, Smith & Wesson and Ruger, we actually observed the manufacturing processes of how these weapons are manufactured.
MR. MELLIN: You mentioned Ruger. Do you know where Rugers are manufactured?
DAVID CAHILL: They have plants in Freeport, New Hampshire, and also Prescott, Arizona.
MR. MELLIN: Do they have a plant in Massachusetts?
DAVID CAHILL: No, they do not.
MR. MELLIN: Is the field of firearms identification generally accepted?
DAVID CAHILL: Yes; it has been for close to 85 years.
MR. MELLIN: Are there treatises that apply to firearms identification?
DAVID CAHILL: Yes, there are.
MR. MELLIN: And are those subject to peer review?
DAVID CAHILL: Yes, they are.
MR. MELLIN: And are those generally accepted in the field?
DAVID CAHILL: Yes.
MR. MELLIN: Are there also generally accepted procedures that you follow to do an identification?
DAVID CAHILL: Yes; we have certain protocols and procedures at the lab itself.
MR. MELLIN: You mentioned protocols. What type of protocols do you follow?
DAVID CAHILL: Well, we have a firearms identification protocol, and it explains step by step of how we recover evidence, how we're to examine it, how we're supposed to generate our reports afterwards.
MR. MELLIN: Approximately how many firearms identifications have you done?
DAVID CAHILL: In excess of 3,000.
MR. MELLIN: And of those thousands, are those subject to peer review? Does someone oversee your work?
DAVID CAHILL: Yes, they do.
MR. MELLIN: And at times do you oversee the work of others?
DAVID CAHILL: Yes, I do.
MR. MELLIN: And how does that process go?
DAVID CAHILL: In regards to making identifications under the microscope, if we were to identify a cartridge case, either to itself or to a firearm, we'd have them put it on the microscope, we'd do the ID, then we would ask another examiner to come and verify our identification. After that's all said and done, after the verification process, we generate our reports. Once the reports are done, they're submitted for technical and administrative review by another -- a supervisor, usually of a higher rank than the person who was issuing the report.
MR. MELLIN: You talked about the Massachusetts state lab. Is that an accredited lab?
DAVID CAHILL: Yes, it is. It's ASCLD accredited.
MR. MELLIN: It is what?
DAVID CAHILL: ASCLD. Association of Crime Lab Directors. It's an organization that certifies labs.
MR. MELLIN: You mentioned you've done over a thousand examinations. Of those over a thousand, are you aware of anyone ever claiming that your work was unreliable?
DAVID CAHILL: No.
MR. MELLIN: Has anyone ever claimed after the fact that any conclusions you rendered or reached was unreliable?
DAVID CAHILL: No.
MR. MELLIN: Have you testified previously as an expert in firearms identification?
DAVID CAHILL: Yes, I have.
MR. MELLIN: Approximately how many times?
DAVID CAHILL: Over a hundred times.
MR. MELLIN: Lieutenant Cahill, if you could just generally describe for us how does someone go about identifying a firearm and whether or not it was used in a shooting?
DAVID CAHILL: When we would recover the firearm, we would examine the firearm first to make sure -- you know, check its operability; check the condition of the firearm; make, model, serial number; note the condition as it's submitted. Once we determine the weapon is safe to fire, we would then test-fire the weapon. We have a facility at the lab to test-fire firearms. We would take those tests that we generated and then go into our microscope room where we have a comparison microscope, and then we would compare the tests from the firearm to the recovered evidence.
MR. MELLIN: Okay. You mentioned a test-fire. If you could just tell us what is that?
DAVID CAHILL: It is we take either -- we could take ammunition that was recovered with the weapon at the scene, or we have a large reference section in our lab of ammunition. What we do is we check the weapon to see what the caliber is, we get the same caliber ammunition, we take it into our test-fire room, we load the weapon and we test-fire it. We fire the weapon.
MR. MELLIN: If you're dealing with a semiautomatic weapon that has shell casings, how do you go about making an identification of shell casings?
DAVID CAHILL: Again, we have -- if the shell casings are recovered by themselves with no weapon, we'd take the shell casings -- first we'd make -- we take them into our workroom, we make note of the make, manufacturer and caliber of the shell casings, record those. Then we bring the shell casings into our microscope room. We then place the microscope -- there's a comparison microscope. There's a stage on the right and the left, and it has one eyepiece so you could look at both stages at the same time. And then we're looking for specific markings left behind on those shell casings generated through the firing process to make our identification.
MR. MELLIN: If you have a number of shell casings but don't have a firearm recovered, are you still able to determine whether or not those shell casings were all fired from a single weapon?
DAVID CAHILL: Yes, we can.
MR. MELLIN: If you have the firearm recovered, are you then able to make a comparison to determine if that firearm fired those shell casings?
DAVID CAHILL: Yes, we can.
MR. MELLIN: And how do you make that comparison?
DAVID CAHILL: Again, we test fire the firearm, we look at the test under the microscope to make sure there's enough microscopic marks left behind on the test to make the identification. Then we take the evidence -- we look at all the evidence first together to make sure that they're all fired -- or they all possess the same microscopic markings. Then we take a sample from the recovered evidence and the test-fires, and we compare those against each other under the microscope and make the identification through the individual microscopic marks left behind.
MR. MELLIN: Are you, as well, able to determine whether or not a recovered projectile or a bullet was fired by a particular weapon?
DAVID CAHILL: Yes, we can.
MR. MELLIN: And how do you go about doing that?
DAVID CAHILL: Again, we test fire the weapon, we recover the projectile, we look for the individual markings left behind on the projectile from the test against the individual markings on the submitted evidence. Again, we bring them to the microscope room, we put the test-fire on one side of the microscope and the recovered evidence on the other side, and we're looking for those striated individual markings left behind during the firing process to make our identification.
MR. MELLIN: And generally, when you're talking about a round of ammunition or a bullet or a projectile, as sometimes you like to refer to it as, what are you looking for on that projectile to make a comparison?
DAVID CAHILL: Okay. Well, what most people call a bullet, we would call it a live round of ammunition. It has four different components to a live round of ammunition. One would be what people would normally refer to as the bullet, we would call it a projectile. That's the casing that contains the projectile. Inside the casing is the powdered charge, and on the base of that casing is the primer.
MR. MELLIN: And if I may have just brought up for the witness right now, your Honor, Exhibit 940.
MR. MELLIN: Do you see Exhibit 940 in front of you?
DAVID CAHILL: I do now, yes.
MR. MELLIN: Very good. Do you recognize what that is?
DAVID CAHILL: Yes, I do.
MR. MELLIN: Is that a photograph of a -- well, you tell me. What is that a photograph of?
DAVID CAHILL: It appears to be a photograph of one live round of ammunition.
MR. MELLIN: Your Honor, if the witness may use this just as a chalk?
THE COURT: All right.
BY MR. MELLIN:
MR. MELLIN: Lieutenant Cahill, looking at Exhibit 940, as you look at that, what do you see on the right side of that photograph?
DAVID CAHILL: That's a ruler or a scale.
MR. MELLIN: That's on the left side.
DAVID CAHILL: That's the projectile -- or the live cartridge, I should say.
MR. MELLIN: Okay. And as you look at that, if you could -- this is a screen that's interactive so you could touch it. As you look at it, what are the component parts that we're looking at?
DAVID CAHILL: Okay. Right here would be the nose or the projectile or the bullet. On here, the brass-colored item is the cartridge case. Inside this cartridge case would be the powder or the propellant for the cartridge. And on the base underneath is the primer. Usually it's silver in color. In order to operate this, you load it into a weapon, the firing pin would then strike the primer, setting off an explosive charge that would ignite the powder inside the cartridge, creating pressure for one to force a projectile down the barrel of the weapon.
MR. MELLIN: All right. And for the record, you indicated that the copper-colored portion of this photograph is what?
DAVID CAHILL: A bullet, or projectile.
MR. MELLIN: Okay. So now the bullet, when there is -- the firing pin hits the bottom of this casing and there causes some type of internal explosion, what happens to the bullet?
DAVID CAHILL: The bullet is forced down the barrel of the weapon.
MR. MELLIN: And as the bullet is being forced out the barrel, what's happening to the bullet?
DAVID CAHILL: On weapons that are rifled, what happens is the projectile is grabbed by the rifling as it's being forced down the barrel. Rifling is designed to impart a spin on the projectile, making it a much more accurate weapon.
MR. MELLIN: Hold on right there. You keep talking about rifling. What do you mean by "rifling"?
DAVID CAHILL: Rifling in weapons is grooves, lands and grooves, that are cut down the length of the inside of the barrel. These are done by, you know, hardened cutters. And they cut actually grooves into the projectile -- excuse me, into the barrel. And during that process, it could be towards the right or to the left.
MR. MELLIN: And what is the purpose of this internal rifling in the barrel of a weapon?
DAVID CAHILL: Again, it imparts a spin on the projectile as it's traveling down the barrel, making it much more accurate.
MR. MELLIN: Just like throwing a football, if you have a tight spiral it's much more accurate than if it flutters?
DAVID CAHILL: Yes.
MR. MELLIN: Okay. So what are you able, as a firearms identifier or examiner, able to do with those rifling marks?
DAVID CAHILL: So what happens, after the projectile travels down, it picks up what we call microscopic individual markings left behind during the -- by the rifling. As the rifling is cut, hardened-steel tools are dragged down the barrel and they cut into the hardened steel of the barrel leaving microscopic imperfections in the barrel. The projectile --
MR. MELLIN: You mean on the bullet or on the barrel?
DAVID CAHILL: On the barrel. When the projectile travels down the barrel, it picks up those microscopic markings and leaves behind marks on the projectile itself.
MR. MELLIN: So the bullet is shot out the barrel. Is that right?
DAVID CAHILL: Yes.
MR. MELLIN: What happens to that casing?
DAVID CAHILL: Depending on what kind of weapon is used, a revolver, the casing would stay inside the weapon itself. A semiautomatic weapon, it would actually be thrown outside the weapon.
MR. MELLIN: When you said a revolver, is that the gun that has the cylinder on it?
DAVID CAHILL: Yeah. It's like what the cowboys used to have. It has a cylinder, it has a number of live rounds. And every time you fire it, the cylinder rotates to the next live cartridge.
MR. MELLIN: And when you say the casing is kicked out, where does it go after it's kicked out?
DAVID CAHILL: Depending on the weapon -- the ejection point is on the right or the left, it's usually -- both weapons have an ejection point on the right side of the weapon. You eject it to the right and somewhere to the rear of the weapon.
MR. MELLIN: And if someone is standing on a street or on a sidewalk or some hard surface and these casings are ejected out, what happens when that casing hits that hard surface?
DAVID CAHILL: Most of the time it will bounce and roll. They won't actually stay where they first hit, they have a possibility of bouncing and rolling.
MR. MELLIN: Now in this case did you do a firearms identification?
DAVID CAHILL: Yes, I did.
MR. MELLIN: And generally what did you do?
DAVID CAHILL: I responded to the scene and recovered all the firearms-related evidence, brought it back to the lab, examined it, generated my report.
MR. MELLIN: As you're going through your testimony, would it help to have a copy of your report in front of you?
DAVID CAHILL: Yes.
MR. MELLIN: Your Honor, if I may approach with Government's Exhibit 1567. I'm not going to introduce it into evidence, but I think it would be helpful if the Lieutenant had it.
THE COURT: Okay.
MR. WATKINS: No objection, your Honor.
THE COURT: Okay.
BY MR. MELLIN:
MR. MELLIN: Lieutenant, just for the record, Exhibit 1567, is that your report?
DAVID CAHILL: Yes, it is.
MR. MELLIN: Okay. And it's a relatively voluminous report. Is that fair to say?
DAVID CAHILL: Yes.
MR. MELLIN: How many pages?
DAVID CAHILL: Thirty-two.
MR. MELLIN: Okay. And what is the date on your report?
DAVID CAHILL: The date it was generated was August 22, 2013.
MR. MELLIN: Generally, when you got to the scene at Watertown, what did you do?
DAVID CAHILL: I checked in with the crime scene services and the detectives from the Middlesex County District Attorney's Office just to let them know I was at the location.
MR. MELLIN: Okay. Prior to arriving at Watertown, what did you do?
DAVID CAHILL: I was at the scene of a shooting in the city of Cambridge on Vassar Street.
MR. MELLIN: How did you end up there?
DAVID CAHILL: I was called to that scene from my home.
MR. MELLIN: And so that was at MIT?
DAVID CAHILL: Yes, it was.
MR. MELLIN: And did you recover the ballistics evidence at MIT as well?
DAVID CAHILL: Yes, I did.
MR. MELLIN: Now, the findings and conclusions that you've reached in this case either regarding the MIT shooting or the Watertown ballistics evidence, were those subject to peer review?
DAVID CAHILL: Yes, they were.
MR. MELLIN: Who reviewed your work?
DAVID CAHILL: My immediate supervisor, Detective Lieutenant Michael Coleman.
MR. MELLIN: Let me talk first about the MIT evidence. What did you recover at MIT?
DAVID CAHILL: At MIT we recovered five 9 mm Luger caliber discharge cartridge casings and two projectiles.
MR. MELLIN: If I could have the witness look at Exhibit 698, please.
MR. MELLIN: Do you recognize Exhibit 698?
DAVID CAHILL: Yes, I do.
MR. MELLIN: What is that?
DAVID CAHILL: That is a 9 mm caliber discharged cartridge case with the Placard No. 1 from the scene at MIT.
MR. MELLIN: I move into evidence and ask to publish 698.
MR. WATKINS: No objection.
THE COURT: I'm told it's already in.
COURT CLERK: It's already in.
THE COURT: If it isn't, it is now.
MR. MELLIN: Thank you. Redundancy.
BY MR. MELLIN:
MR. MELLIN: Lieutenant Cahill, do you see Exhibit 698?
DAVID CAHILL: Yes, I do.
MR. MELLIN: Okay. And that casing that you see there, that is one of the three that you recovered outside the car. Is that right?
DAVID CAHILL: Yes, it is.
MR. MELLIN: Okay. If I could have you look at Exhibit 699.
MR. MELLIN: Not knowing whether or not that's in, your Honor --
MR. MELLIN: Well, first, do you recognize that?
DAVID CAHILL: Yes, I do.
MR. MELLIN: What is that?
DAVID CAHILL: That is a second shell, 9 mm Luger caliber discharged shell casing from the scene at MIT with Placard No. 2.
MR. MELLIN: I'm told that's already in as well, your Honor. If I can please have that published?
MR. MELLIN: And again, just for the record, what do you see in that photo?
DAVID CAHILL: A 9 mm Luger caliber discharged cartridge case.
MR. MELLIN: And then if I could have you look at 701?
THE COURT: Is that in? Okay.
MR. MELLIN: Do you recognize 701?
DAVID CAHILL: Yes, I do.
MR. MELLIN: What is that?
DAVID CAHILL: That is a third 9 mm Luger caliber discharged cartridge case with the Placard No. 3 next to it.
MR. MELLIN: And all three of these casings were found outside of Officer Collier's vehicle. Is that right?
DAVID CAHILL: Yes, to the rear of the cruiser.
MR. MELLIN: If I could have you look at Exhibit 702, please. Do you recognize Exhibit 702?
DAVID CAHILL: Yes, I do.
MR. MELLIN: What is that?
DAVID CAHILL: That is the front seat of Officer Collier's cruiser.
MR. MELLIN: Is that a fair and accurate photograph of how the cruiser looked?
DAVID CAHILL: Yes.
MR. MELLIN: I'd move into evidence Exhibit 702 if it's not already in.
MR. WATKINS: No objection.
THE COURT: Okay.
(Government Exhibit No. 702 received into evidence.)
MR. MELLIN: Ask to publish it, your Honor.
BY MR. MELLIN:
MR. MELLIN: Lieutenant Cahill, as you look at Exhibit 702, what do you see there?
DAVID CAHILL: In the center of the seat, in the pool of blood is the 9 mm Luger caliber discharged cartridge case.
MR. MELLIN: And if we could pull up Exhibit 704, please.
MR. MELLIN: Do you recognize Exhibit 704?
DAVID CAHILL: Yes. That's a close-up of the seat with the discharged cartridge casing.
MR. MELLIN: Your Honor, I'd move into evidence and ask to publish Exhibit 704.
MR. WATKINS: No objection.
(Government Exhibit No. 704 received into evidence.)
BY MR. MELLIN:
MR. MELLIN: Lieutenant Cahill, as you look at Exhibit 704, there's a casing in the middle of that photo. Is that right?
DAVID CAHILL: Yes; right on the scale where it says "130."
MR. MELLIN: I was just going to ask you to circle that, if you don't mind.
DAVID CAHILL: (Witness complies.)
MR. MELLIN: All right. And for the record, it's right in the middle of the photograph?
DAVID CAHILL: Yes, it is.
MR. MELLIN: Okay. And this is a -- 704 is a closer photograph than 702, the one we just saw. Is that right?
DAVID CAHILL: Yes.
MR. MELLIN: And again for the record, this is the front driver's seat?
DAVID CAHILL: Yes, it is.
MR. MELLIN: All right. If I could have you look at Exhibit 708, please.
MR. MELLIN: I believe that's in, your Honor.
MR. MELLIN: Do you see what 708 is?
DAVID CAHILL: Yes, I do.
MR. MELLIN: What is that a photograph of?
DAVID CAHILL: A 9 mm Luger caliber discharged cartridge casing that was located on the passenger-side seat on top of Officer Collier's hat or cover.
MR. MELLIN: So as we look at 708, this is a close-up and his hat is to the right?
DAVID CAHILL: Yes.
MR. MELLIN: And are those now the five casings that you recovered from the scene, three outside and these two in the car?
DAVID CAHILL: Yes.
MR. MELLIN: All right. And if I could have you look at 710, please.
MR. MELLIN: I believe 710 is already in as well.
MR. MELLIN: Do you see Exhibit 710?
DAVID CAHILL: Yes, I do.
MR. MELLIN: What is that?
DAVID CAHILL: That is the passenger front seat of Officer Collier's cruiser.
MR. MELLIN: And what do you see, as a firearms examiner, that's of note to you?
DAVID CAHILL: In the center of the picture is a copper-colored -- it's a copper jacket or lead-spent projectile.
MR. MELLIN: Is that the top of one of these rounds that we were talking about?
DAVID CAHILL: Yes, it is.
MR. MELLIN: In addition to this projectile that was recovered in the car, at some point did you recover additional projectiles?
DAVID CAHILL: Yes, I did.
MR. MELLIN: How did you go about recovering additional projectiles?
DAVID CAHILL: The next day Officer Collier's autopsy was performed and three additional copper jacket lead-spent projectiles were received from the chief medical examiner. The day after that we returned to the Cambridge PD and examined Officer Collier's cruiser a second time, and a fifth copper jacket or lead-spent projectile was recovered from underneath the carpeting on the driver's side front seat.
MR. MELLIN: How did you go about recovering that?
DAVID CAHILL: We had to remove the seat, and we removed the carpeting from the cruiser.
MR. MELLIN: And how is it that it would have been able to fall under the carpeting?
DAVID CAHILL: It looks like when it was fired, they hit the center console inside the cruiser and it ricocheted down and under the carpeting.
MR. MELLIN: If I could have you look at Exhibit 726 for just a moment.
MR. MELLIN: If I may approach, your Honor?
THE COURT: Yes.
BY MR. MELLIN:
MR. MELLIN: Do you recognize what Exhibit 726 is?
DAVID CAHILL: Yes, I do.
MR. MELLIN: What is that?
DAVID CAHILL: This is a 9 mm Luger caliber discharged cartridge case with Number 13-08091. This is from the scene in Cambridge, Officer Collier's shooting.
MR. MELLIN: And how are you able to recognize that as one of the casings from that shooting?
DAVID CAHILL: One, it's my handwriting on it.
MR. MELLIN: And if you could, just open that up.
DAVID CAHILL: (Witness complies.)
MR. MELLIN: Is that one of the casings recovered?
DAVID CAHILL: Yes, it is.
MR. MELLIN: Now, as you look at that, what do you see on the -- kind of the headstamp of that casing?
DAVID CAHILL: On the base of the cartridge case is the manufacturer headstamp. It says "Win," and underneath that, "9 mm Luger."
MR. MELLIN: What does "Win" mean, do you know?
DAVID CAHILL: "Win" is an abbreviation for the manufacturer, which is Winchester.
MR. MELLIN: And it says "9 mm Luger"?
DAVID CAHILL: Yes. That's the caliber designation for this cartridge case.
MR. MELLIN: Now, when we're talking about caliber, like 9 mm, can you describe briefly kind of what are the various types of calibers?
DAVID CAHILL: Caliber has to do with the diameter of a projectile that travels down the barrel. So in this case, "9 mm" would mean it was 9 mm in diameter, or roughly .355 inches in diameter.
MR. MELLIN: What are some other calibers that are used?
DAVID CAHILL: There's .40 caliber, there's .45 caliber. There's hundreds of different calibers.
MR. MELLIN: Okay. What about like a 380 or a 38?
DAVID CAHILL: Yes, .380, .38, 9 mm, those are all in the same .38 caliber class, which mostly means the diameter is pretty much the same but the weight of the projectile is different. Like a .380, a normal weight for that would be 95 grams, a 9 mm is around 115 grams, and .38s can get up to like 140 grams.
MR. MELLIN: And what about a .40 caliber?
DAVID CAHILL: A .40 caliber about 180 grams, but again, that's not in the same caliber class because a .40 caliber is .40 inches in diameter. So it's a different caliber class than 9 mm.
MR. MELLIN: And again, a .45?
DAVID CAHILL: A .45, again, is .45 inches in diameter, and they can range from 230 grams, a little lighter, a little heavier depending on the manufacturer.
MR. MELLIN: Okay. Is a .45 caliber weapon able to fire a 9 mm round?
DAVID CAHILL: It's not designed to, no.
MR. MELLIN: And vice versa, if you have a .45 caliber round, are you able to put that into a 9 mm?
DAVID CAHILL: It's physically impossible to do that.
MR. MELLIN: Now, when you recovered all those five casings, what were you able to determine about them?
DAVID CAHILL: I brought them back to the lab, I made a microscopic comparison. I made a determination that they were all fired by the same unknown weapon.
MR. MELLIN: And at that point unknown?
DAVID CAHILL: Yes.
MR. MELLIN: Okay. And again, just to briefly describe it, how can you compare a casing and determine that it's fired by the same weapon?
DAVID CAHILL: Again, we're looking for the individual markings left behind during the firing process. When the weapon's fired, again, the firing pin strikes the primer, sets off the charge. And the primer, which ignites the powder, develops between 15- and 20,000 pounds of pressure inside the chamber of that weapon. The pressure does two things: In a semiautomatic pistol, one, it forces the projectile down the barrel, outside the barrel. In a semiautomatic pistol, what happens is that casing is then slammed up against what's called the breech face of the weapon, and it's where the firing pin comes through, and it stamps those individual microscopic markings left behind during the manufacturing process onto the base of that cartridge. Again, the firing pin also striking it leaves an indentation in the primer, leaving some individual markings behind.
MR. MELLIN: And all of those markings were consistent for all five of those casings?
DAVID CAHILL: Yes, they were.
MR. MELLIN: Now, if we can just briefly turn to the Watertown -- not so briefly, but Watertown --
THE COURT: No, if you're going to do that, why don't we pause and take the midmorning recess.
MR. MELLIN: All right.
COURT CLERK: All rise for the Court and the jury. The Court will take the morning recess.
(The Court and jury exit the courtroom and there is a recess in the proceedings at 10:56 a.m.)
COURT CLERK: All rise for the Court and the jury.
(The Court and jury enter the courtroom at 11:26 a.m.)
COURT CLERK: Be seated.
THE COURT: Proceed.
MR. MELLIN: Thank you, your Honor. Your Honor, I'd also move into evidence Exhibit 726, which was the shell casing recovered from the scene at MIT.
MR. WATKINS: I have no objection.
THE COURT: All right. Do you want it shown?
MR. MELLIN: No, that's fine. He's already talked about it.
THE COURT: Oh, the actual object?
MR. MELLIN: Yes.
(Government Exhibit No. 726 received into evidence.)
BY MR. MELLIN:
MR. MELLIN: Lieutenant Cahill, when you responded to Watertown, did you locate weapons at that scene?
DAVID CAHILL: Yes, I did.
MR. MELLIN: Did you locate a pellet gun as well as a 9 mm?
DAVID CAHILL: Yes, I did.
MR. MELLIN: If I may approach, your Honor, with Exhibit 934.
MR. MELLIN: Do you recognize Exhibit 934?
DAVID CAHILL: Yes, I do.
MR. MELLIN: And what is that?
DAVID CAHILL: That's a pellet gun I retrieved from Laurel Street in Watertown.
MR. MELLIN: Your Honor, the government would move that into evidence and ask if it may be published.
MR. WATKINS: No objection.
THE COURT: All right.
(Government Exhibit No. 934 received into evidence.)
BY MR. MELLIN:
MR. MELLIN: If I may just have you hold it up and show it to the ladies and gentlemen of the jury.
DAVID CAHILL: (Witness complies.)
MR. MELLIN: And Lieutenant Cahill, when you look at that pellet gun, how would you describe it?
DAVID CAHILL: It's an Airsoft pellet gun. The caliber's .177. It's a copy of a Smith & Wesson M&P 40 real gun.
MR. MELLIN: What do you mean by "it's a copy"?
DAVID CAHILL: It's not manufactured by Smith & Wesson; it's just a knockoff of one of their firearms.
MR. MELLIN: Okay. You also recovered a 9 mm?
MR. MELLIN: If I may approach with Exhibit 928, your Honor, and take back that other exhibit.
THE COURT: All right.
BY MR. MELLIN:
MR. MELLIN: Do you recognize Exhibit 928?
DAVID CAHILL: Yes, I do.
MR. MELLIN: What is that?
DAVID CAHILL: It's the Ruger 9 mm caliber Model P95 semiautomatic pistol I recovered from the scene at Laurel Street.
MR. MELLIN: If I may pull up 948-213, which is in evidence.
MR. MELLIN: Do you see the photograph in front of you?
DAVID CAHILL: Yes, I do.
MR. MELLIN: What is that?
DAVID CAHILL: That's a picture of the weapon that I recovered from Laurel Street.
MR. MELLIN: Is that the 9 mm?
DAVID CAHILL: Yes, it is.
MR. MELLIN: You mentioned something about a serial number?
DAVID CAHILL: Yes. The serial number has been defaced, or obliterated, on the weapon.
MR. MELLIN: As you look at 948-231, can you circle where that serial number was located?
DAVID CAHILL: (Witness complies.)
MR. MELLIN: For the record, it's the silver plate on the handle of the weapon?
DAVID CAHILL: Yes, it is.
MR. MELLIN: In addition to the gun being in that box, Exhibit 928, is there another item in there?
DAVID CAHILL: Yes, there is.
MR. MELLIN: What is that?
DAVID CAHILL: It's the magazine for that weapon.
MR. MELLIN: Your Honor, I would move in 928 and -- which includes both the magazine and the weapon.
THE COURT: I'm told it's in already, but if not it will be.
MR. WATKINS: Yeah.
MR. MELLIN: Thank you.
If I could have Lieutenant Cahill hold that up as well, your Honor, and not point it at anyone?
DAVID CAHILL: The weapon?
BY MR. MELLIN:
MR. MELLIN: Yes. And just for the record, is it rendered safe?
DAVID CAHILL: Yes.
MR. MELLIN: How is it rendered safe?
DAVID CAHILL: It has a cable lock going through the slide of the weapon down the barrel.
MR. MELLIN: Okay. Is there any ammunition in it?
DAVID CAHILL: No, there is not.
MR. MELLIN: All right.
DAVID CAHILL: This is a Ruger Model P95 semiautomatic pistol.
MR. MELLIN: And what caliber?
DAVID CAHILL: 9 mm.
MR. MELLIN: And if I could have you hold up the magazine?
DAVID CAHILL: This is the magazine that was recovered with the weapon on Laurel Street.
MR. MELLIN: All right. And as you hold that up, do you -- there's a bottom portion of that that is larger than the top portion. Is that right?
DAVID CAHILL: Yes, it is.
MR. MELLIN: And what is that?
DAVID CAHILL: This is an extended magazine, so when you insert it inside the weapon, the magazine sits below the grip of the weapon. It's just like a plastic cover on the magazine.
MR. MELLIN: And as we look at 948-231, do you see that magazine actually in that weapon?
DAVID CAHILL: Yes, it is.
MR. MELLIN: Now, for the record, what is a magazine?
DAVID CAHILL: A magazine in a semiautomatic pistol is what holds the ammunition for that weapon. In order to fire this weapon, you load the right caliber ammunition inside the magazine, you place the magazine inside the grip, or the bottom of the weapon, in order to load the weapon. Then on the top of the weapon where the barrel is, where I showed where the cable lock was coming out is called the slide. You pull onto the slide, pull it to the rear. It's under spring tension. As you pull it to the rear and release it, it strips off the live ammunition on the top of that magazine. In order to operate this weapon, you then pull the trigger, the trigger releases the firing pin, the firing pin strikes the primer, again, develops pressure inside the cartridge case. The pressure forces the projectile down the barrel, and the remaining pressure operates the slide of the weapon, or the top. It pushes that slide to the rear. So it pulls it all the way to the rear, and the spring tension of the weapon pulls it forward, strips off the next live cartridge, and the weapon is ready to fire again up until you've fired all the ammunition that is inside the magazine.
MR. MELLIN: Now, when you've fired all of the ammunition, at that point this magazine is empty, right?
DAVID CAHILL: Yes, it is.
MR. MELLIN: Is there a way to eject that magazine and put either a new one in or to reload the one that you had?
DAVID CAHILL: Yes. On the side of the weapon right by the trigger guard is called a magazine release. You press that button, it releases the catch that's on the magazine, the magazine can then be removed from the weapon.
MR. MELLIN: And the magazine that we're talking about that's Exhibit 928, is that an extended magazine?
DAVID CAHILL: Yes, it is.
MR. MELLIN: What does that mean?
DAVID CAHILL: The original magazine for this weapon, went to the bottom of the weapon, usually holds ten live cartridges. This magazine holds 18. So in order to fit the 18 cartridges, the magazine has to sit below the bottom of the grip of the weapon.
MR. WATKINS: Your Honor, may I interrupt and have a moment with Mr. Mellin?
(Counsel confer off the record.)
MR. MELLIN: Your Honor, we had previously listed the magazine as 931. We'll just do that for the record.
THE COURT: So you'll take it out of 928 and make it 931?
MR. MELLIN: Correct.
(Government Exhibit No. 928 is replaced by Exhibit No. 931.)
BY MR. MELLIN:
MR. MELLIN: In addition to this magazine that you see inside of the handgun that is recovered, did you recover other magazines as well?
DAVID CAHILL: Yes, I did.
MR. MELLIN: What did you recover those from?
DAVID CAHILL: One magazine for this weapon was recovered at the scene by the Honda on Laurel Street, the second magazine was recovered from the SUV at the Watertown PD.
MR. MELLIN: If I may approach, your Honor?
THE COURT: All right.
BY MR. MELLIN:
MR. MELLIN: Lieutenant Cahill, I just handed you two items, Exhibit 894 and Exhibit 893. Do you recognize Exhibit 894?
DAVID CAHILL: Yes, I do.
MR. MELLIN: What is that?
DAVID CAHILL: It's the magazine that I recovered from the street -- on Laurel Street in Watertown.
MR. MELLIN: Wait. Which one are we talking about?
DAVID CAHILL: This.
MR. MELLIN: All right. What's the exhibit number on that one?
DAVID CAHILL: 933.
MR. MELLIN: All right. You're trying to trick me. All right. I had said 894 but let's talk about 933. That's the magazine recovered on Laurel Street?
DAVID CAHILL: Yes, it is.
MR. MELLIN: Okay. And then 894, do you see that?
DAVID CAHILL: Yes, I do.
MR. MELLIN: What is that?
DAVID CAHILL: This is the magazine that was recovered out of the Mercedes SUV by my unit at the Watertown Police Department.
MR. MELLIN: And did that magazine actually have live rounds in it?
DAVID CAHILL: Yes, it did.
MR. MELLIN: How many live rounds did it have in it?
DAVID CAHILL: It had seven live cartridges in the magazine.
MR. MELLIN: If I could have you --
MR. MELLIN: Just the witness, please.
MR. MELLIN: -- look at Exhibit 931. I'm sorry. 931 is -- I take that back. It's 895. If I could have you look at Exhibit 895. Do you recognize that?
DAVID CAHILL: Yes, I do. It's the magazine that was inside the Mercedes SUV.
MR. MELLIN: I'd move into evidence Exhibit 895.
MR. WATKINS: No objection.
THE COURT: Okay.
(Government Exhibit No. 895 received into evidence.)
MR. MELLIN: If I may have that published, please.
BY MR. MELLIN:
MR. MELLIN: Lieutenant Cahill, as you look at that photograph, you mentioned there was -- how many rounds were in that?
DAVID CAHILL: Seven.
MR. MELLIN: Okay. And how many does that magazine actually hold?
DAVID CAHILL: Ten.
MR. MELLIN: Thank you. When you went to the --
MR. MELLIN: You can pull that down, Mr. Bruemmer.
MR. MELLIN: When you went to the scene on Laurel Street, did you recover the casings that were on that scene?
DAVID CAHILL: Yes, I did.
MR. MELLIN: And in total, how many casings did you recover?
DAVID CAHILL: In total, 266.
MR. MELLIN: And of those 266, how many were 9 mm?
DAVID CAHILL: Fifty-six.
MR. MELLIN: Did you also recover projectiles, or these bullets?
DAVID CAHILL: Yes, I did.
MR. MELLIN: How many bullets or projectiles did you recover?
DAVID CAHILL: Ninety-five.
MR. MELLIN: And could you -- of the projectiles, do you remember how many were a Ruger type of a projectile?
DAVID CAHILL: There were eight 9 mm caliber projectiles.
MR. MELLIN: That you were able to find?
DAVID CAHILL: Out of those 95, yes.
MR. MELLIN: Okay. So of the 56 casings of 9 mm, you were only able to find six to eight of those projectiles?
DAVID CAHILL: Yes.
MR. MELLIN: At some point did you analyze those 56 casings?
DAVID CAHILL: Yes, I did.
MR. MELLIN: What were you able to determine about your analysis of those casings?
DAVID CAHILL: Upon examining the 56 recovered, I made the determination they were all fired by the same unknown weapon.
MR. MELLIN: And when you say "the same unknown weapon," what type of a weapon would that have been?
DAVID CAHILL: A 9 mm caliber weapon.
MR. MELLIN: Now, in addition to saying there was an unknown weapon, did you at some point attempt to determine whether or not those 56 casings were related to Exhibit 928, the 9 mm you recovered on the scene?
DAVID CAHILL: Yes, I did.
MR. MELLIN: And what did you determine?
DAVID CAHILL: I test-fired the 9 mm, I compared the test from the 9 mm to the 56 cartridges recovered from the scene, and it was my opinion the 56 live -- the 56 discharged cartridge casings were fired by the 9 mm Ruger Model P95 semiautomatic pistol.
MR. MELLIN: You mentioned the other casings that were on the scene. There were 56 9 mm. Were there other rounds as well that were fired?
DAVID CAHILL: Yes, there were -- approximately 210 other rounds that were -- casings that were recovered.
MR. MELLIN: And were you able to determine that those -- well, did you receive the firearms of Watertown police and other police that responded to the scene?
DAVID CAHILL: Yes, I did.
MR. MELLIN: And were you able to determine that none of the police weapons fired any of the 56 9 mm weapon -- rounds that were recovered?
DAVID CAHILL: Yes, I was.
MR. MELLIN: How were you able to determine that?
DAVID CAHILL: One, there was a different caliber class; two, I test-fired all of the submitted weapons of the police agencies, and I identified all of the cartridges of those 210 back to those police weapons.
MR. MELLIN: And in addition, you excluded, then, the 9 mm from those rounds?
DAVID CAHILL: From those weapons, yes.
MR. MELLIN: Okay. And on the flip side of that, these .40 caliber -- or what other caliber were the police firing?
DAVID CAHILL: There was .40 and .45 caliber.
MR. MELLIN: And so were you able to exclude those .40 and .45s as firing the 9 mm casings?
DAVID CAHILL: Yes, I was.
MR. MELLIN: When you did your comparison testing, did you actually take photographs of the analyses you were doing?
DAVID CAHILL: Yes, I did.
MR. MELLIN: If I could have you look just at Exhibit 943, please. Do you recognize what Exhibit 943-01 is?
DAVID CAHILL: Yes, I do.
MR. MELLIN: What is that?
DAVID CAHILL: It's a microscopic comparison -- a picture of a microscopic comparison I did at the lab.
MR. MELLIN: And is that from the MIT shooting?
DAVID CAHILL: Yes, it is.
MR. MELLIN: Okay.
MR. MELLIN: Your Honor, if I may use 943-01 just as a chalk for the witness to explain.
THE COURT: Okay.
MR. MELLIN: If I may have that published?
BY MR. MELLIN:
MR. MELLIN: Lieutenant Cahill, as we look at Exhibit 943-01, what are we looking at?
DAVID CAHILL: It's a side-by-side image from a picture of what I was looking at on the comparison microscope back at the lab. If you look on the left side of that image, there's Item -714, which was one of the rounds or projectiles that was recovered from the MIT shooting. On the right-hand side of the picture is the test-fire from the Ruger that I compared it to.
MR. MELLIN: Okay. So this is actually a comparison of the projectiles?
DAVID CAHILL: Yes, it is.
MR. MELLIN: Okay. Now, the projectiles are the two that are in the police cruiser. Is that right?
DAVID CAHILL: Yes.
MR. MELLIN: In addition to the three from the autopsy. Is that right?
DAVID CAHILL: Yes.
MR. MELLIN: All right. As you look at 943-01, can you circle on the screen kind of the area that you're talking about that you were able to analyze, show the comparison?
DAVID CAHILL: Yes. This red box is the area I was looking at that I -- one of the areas I was looking at that I made my identification on.
MR. MELLIN: And as a trained examiner, what do you see in that photograph and in that red box?
DAVID CAHILL: I see the striated -- you know, microscopic -- individual markings left behind from the barrel of the Ruger imparted on the projectiles. So I used them to make my identifications.
MR. MELLIN: So as you look at this under a microscope, how are you able to make a finding or come to a conclusion that that's the same weapon that fired the bullet?
DAVID CAHILL: If you see inside the circle or the red box, those lines that match up -- those are what we call striated toolmarks, and they match up from the test-fire on the right to the evidence on the left. And this is just one area that we're using as an identification. If you were to then roll that projectile, there would be several other areas that we would use to make that identification.
MR. MELLIN: And we're actually just looking at one of the areas of -- or one of the photographs of the areas of comparison. Is that right?
DAVID CAHILL: Yes, it is.
MR. MELLIN: There are several others in addition?
DAVID CAHILL: Yes, there are.
MR. MELLIN: If I could please have Exhibit 733 pulled up, which is already in evidence.
MR. MELLIN: What is Exhibit 733?
DAVID CAHILL: That would be one of the projectiles from the autopsy of the chief medical examiner.
MR. MELLIN: Now, when you are able to make a comparison -- when you were making the comparison of this projectile to a test-fire projectile, as we look at Exhibit 733, how were you making that comparison?
DAVID CAHILL: Well, it's tough to see from this picture but it's probably sitting on its base. So if you look at the base of the projectile, we're looking for the rifling on that projectile. If you look at those inner marks inside the rifling, those individual marks that we're comparing against from the test-fires.
MR. MELLIN: And so even on something that is deformed like this projectile that has gone through a skull, you're still able to make those determinations?
DAVID CAHILL: Not every time but in this case I was able to.
MR. MELLIN: If I could have you please look at Exhibit 733 -- excuse me -- 735. Again, is this one of the projectiles that was recovered from inside the skull of Sean Collier?
DAVID CAHILL: Yes, it was.
MR. MELLIN: All right. And even though it is deformed, you're still able to make your conclusions?
DAVID CAHILL: Yes, I am.
MR. MELLIN: Okay. And then finally, 737: Is that another one of the projectiles recovered from inside the skull of Officer Sean Collier?
DAVID CAHILL: Yes, it is.
MR. MELLIN: And even though that one looks even more deformed than the other, you're still able to make a determination?
DAVID CAHILL: Yes, I was.
MR. MELLIN: At times are you unable to make determinations?
DAVID CAHILL: Not on the projectiles from the MIT scene. All five were identified back to the weapon that was recovered from Watertown.
MR. MELLIN: I'm sorry. I asked a really poor question. I was asking in general, at times are you unable to make an identification because there are not enough markings on a projectile?
DAVID CAHILL: Yes.
MR. MELLIN: But in this case you were able to identify all three of these casings -- or projectiles?
DAVID CAHILL: Yes, I was.
MR. MELLIN: In addition to the weapon, the two weapons and the casings, did you also recover live rounds at the scene?
DAVID CAHILL: Yes, I did.
MR. MELLIN: Okay. If I may take back most of that.
MR. MELLIN: And, your Honor, if I may approach with Exhibit 935.
MR. MELLIN: Do you recognize Exhibit 935?
DAVID CAHILL: Yes, I do.
MR. MELLIN: What is that?
DAVID CAHILL: It's a box of Winchester 9 mm Luger caliber ammunition that was recovered from the Laurel Street scene.
MR. MELLIN: I'd move into evidence Exhibit 935.
MR. WATKINS: No objection.
THE COURT: Okay.
(Government Exhibit No. 935 received into evidence.)
BY MR. MELLIN:
MR. MELLIN: Are there still live rounds in that box?
DAVID CAHILL: Yes, there are.
MR. MELLIN: How many live rounds are still in the box?
DAVID CAHILL: There are four.
MR. MELLIN: If I could have the witness please look at Exhibit 941. Actually, if I could have him look at Exhibit 866. I believe it's in evidence.
MR. MELLIN: Do you recognize Exhibit 866?
DAVID CAHILL: Yes, I do.
MR. MELLIN: And as you look -- is that a photograph of Watertown, on Laurel Street?
DAVID CAHILL: Yes, it is.
MR. MELLIN: Okay. Is that from the crime scene search?
DAVID CAHILL: Yes, it is.
MR. MELLIN: And the box of ammunition that you have in front of you, do you see that in this photograph?
DAVID CAHILL: No, I do not.
MR. MELLIN: All right. Do you remember seeing backpacks out there?
DAVID CAHILL: Yes, I do.
MR. MELLIN: If I blow that up, do you see the box that we're talking about?
DAVID CAHILL: Yes, I do.
MR. MELLIN: Where do you see it?
DAVID CAHILL: The lower left-hand corner right by where Placard 109...
MR. MELLIN: Lieutenant Cahill, I'm not sure if I asked you, but the projectiles that were recovered on the scene on Laurel Street, were you able to tie those back to the 9 mm as well?
DAVID CAHILL: Yes, I was.
MR. MELLIN: And those are the six to eight we were talking about?
DAVID CAHILL: Yes.
MR. MELLIN: And did you do a comparison of those as well?
DAVID CAHILL: Yes, I did.
MR. MELLIN: If I can have just the witness, please, look at Exhibit 944.
MR. MELLIN: Do you recognize Exhibit 944-01?
DAVID CAHILL: Yes, I do.
MR. MELLIN: What are we looking at there?
DAVID CAHILL: It's a picture of one of my comparisons under the microscope. On the left-hand side of the screen is the test-fire from the recovered weapon, and on the right-hand side of the screen, it's my Item 4-89, both 9 mm Luger caliber discharged cartridge casings.
MR. MELLIN: Again, your Honor, I would ask to publish it just as a chalk.
THE COURT: Okay.
BY MR. MELLIN:
MR. MELLIN: As 944-01 comes up, is this just one of a series of microscopic photos that you took?
DAVID CAHILL: Yes, it is.
MR. MELLIN: Okay. Now, if you can please describe for the ladies and gentlemen what it is you see in that.
DAVID CAHILL: On the screen you see a microscopic picture of what I was looking through under the microscope. Again, on the left-hand side it's a split screen, so if you see the line going straight down the middle of the picture, on the left-hand side is the test-fire I conducted from the 9 mm Ruger P95 I recovered from the scene, and on the right-hand side is one of the discharged cartridge casings, my Item No. 4-89, that was recovered from the scene at Watertown.
MR. MELLIN: And similar to Exhibit 943, there's an area of agreement that you have in a red box?
DAVID CAHILL: Yes. If you like, I can circle it or --
MR. MELLIN: Please.
DAVID CAHILL: (Witness complies.) If you look inside the circle, there's a red box in there which we call the "area of agreement." It's the individual microscopic markings on that cartridge casing that we compared one to the other that I was able to determine that that was fired by the Ruger.
MR. MELLIN: And again, are there other areas of agreement in addition just something like this?
DAVID CAHILL: Yes, there are.
MR. MELLIN: All right.
MR. MELLIN: With the Court's indulgence.
(Counsel confer off the record.)
MR. MELLIN: At one point you mentioned that the weapon recovered is a Ruger 9 mm. Is that right?
DAVID CAHILL: Yes, it is.
MR. MELLIN: And then at another point you mentioned something called "Luger." Do you know what that was about?
DAVID CAHILL: Yes.
MR. MELLIN: What was that?
DAVID CAHILL: Ruger is the manufacturer of the firearm; Luger is the caliber designation of the weapon. So a Luger -- a 9 mm Luger is the caliber designation developed by Ruger before World War I as a certain weapon for the German Army.
MR. MELLIN: I may have failed to ask you this, but based on your analysis of the scene at MIT as well as the recovery of the projectiles from Officer Sean Collier, were you able to make a determination that all five of those projectiles were fired by that 9 mm Ruger?
DAVID CAHILL: Yes, I was.
MR. MELLIN: And based on your analyses of the evidence found at the scene, were all 56 of the 9 mm shell casings tied to that exact same 9 mm Ruger?
DAVID CAHILL: Yes, they were.
MR. MELLIN: Your Honor, I'd move into evidence Exhibit 933.
MR. WATKINS: No objection.
THE COURT: Okay.
(Government Exhibit No. 933 received into evidence.)
MR. MELLIN: Thank you. Nothing further.
CROSS-EXAMINATION BY MR. WATKINS:
MR. WATKINS: It's still good morning, Lieutenant.
DAVID CAHILL: Good morning, sir.
MR. WATKINS: I'm putting before you Exhibits 928, which is the Ruger, 931, which is the extended magazine, and then 934 is the pellet gun?
DAVID CAHILL: Yes.
MR. WATKINS: Would you take out Item 931, which is the extended magazine from the Ruger.
DAVID CAHILL: (Witness complies.)
MR. WATKINS: And just hold it up.
DAVID CAHILL: (Witness complies.)
MR. WATKINS: So you work in the Firearms Identification Section of the Massachusetts State Police lab. Is that correct?
DAVID CAHILL: Yes.
MR. WATKINS: And there are other divisions and other laboratories within the Massachusetts State Police?
DAVID CAHILL: Yes.
MR. WATKINS: Forensic Services Group, Firearms Identification Section, a whole host of laboratories?
DAVID CAHILL: Yes.
MR. WATKINS: And when you collect evidence at the scene, for example, the Ruger, the extended magazine and the pellet gun, you're not the first one that analyzes something necessarily. Is that correct?
DAVID CAHILL: That's correct.
MR. WATKINS: So in this case before you did any kind of analysis, those items went to the fingerprint identification section?
DAVID CAHILL: Yes, it did.
MR. WATKINS: And all three of them were analyzed for fingerprints, correct?
DAVID CAHILL: Correct.
MR. WATKINS: And reports came with those fingerprint results, right?
DAVID CAHILL: They generated reports but I never received them.
MR. WATKINS: But those reports follow along with the weapon as it goes through the Massachusetts State Police system?
DAVID CAHILL: Yes, they generated it.
MR. WATKINS: And did you -- well, do you know whether the items were compared to the fingerprints of Jahar Tsarnaev and Tamerlan Tsarnaev?
DAVID CAHILL: I do not.
MR. WATKINS: But a report would have been generated in the ordinary course?
DAVID CAHILL: Yes, they would have.
MR. WATKINS: Now, I want to put up in front of you what's been previously admitted as Exhibit 775. Have you seen that map before?
DAVID CAHILL: I'm not exactly sure of this one but I've seen diagrams of the scene.
MR. WATKINS: And you recognize that to be a diagram of the Laurel and Dexter area?
DAVID CAHILL: Yes.
MR. WATKINS: And this is the area from which you collected items on the morning of April 19th?
DAVID CAHILL: Yes.
MR. WATKINS: And that was something done by you personally after other folks had done other collection or other identification of items there?
DAVID CAHILL: Yes, myself and other members of my unit.
MR. WATKINS: So we heard from -- for example, Trooper Tanguay was there first, and then Trooper Dowd came in and did the GPS, and then you came in. Is that --
DAVID CAHILL: When they were all done, yes, I recovered everything.
MR. WATKINS: And there was videotaping done and photographs being done, right?
DAVID CAHILL: Yes.
MR. WATKINS: And there were several teams all around this area doing similar work, right?
DAVID CAHILL: Yes.
MR. WATKINS: So just to be clear, the 9 mm cartridges you collected were all from around this general area, right?
DAVID CAHILL: Yes. The majority, yes.
MR. WATKINS: Trooper Dowd will tell us precisely where they are, but as a general matter they were up in this area of the Watertown cruiser and the Civic, right?
DAVID CAHILL: Yes.
MR. WATKINS: And none were collected down in this area, which is the actual intersection of Laurel and Dexter, right?
DAVID CAHILL: Correct.
MR. WATKINS: So you told us a total of 266 identifiable rounds shot around that area?
DAVID CAHILL: Casings, yes.
MR. WATKINS: I'm sorry?
DAVID CAHILL: Discharged cartridge casings, yes.
MR. WATKINS: Discharged cartridge casings. There were projectiles -- some projectiles you were able to find also, correct?
DAVID CAHILL: Yes.
MR. WATKINS: And these would be both 9 mm projectiles and also law enforcement projectiles, .40 caliber and .45 caliber, right?
DAVID CAHILL: Yes.
MR. WATKINS: And subtracting the 56 cartridges from the Ruger, that leaves 210 cartridges unaccounted for outside of the Ruger, not unaccounted for -- because you did account for all of them. Is that correct?
DAVID CAHILL: Yes.
MR. WATKINS: You had access to every law enforcement weapon that was fired at that scene on that morning, correct?
DAVID CAHILL: I believe so, yes.
MR. WATKINS: Obviously, if somebody fired and didn't report it --
DAVID CAHILL: I never found -- I never not had a cartridge casing match back to a gun.
MR. WATKINS: Right. You matched every single one of them found down there to one of those, right?
DAVID CAHILL: Yes.
MR. WATKINS: And every one of them, except for the 9 mm casings, were to law enforcement weapons, right?
DAVID CAHILL: Yes.
MR. WATKINS: And Mr. Mellin was asking you about the different calibers. The vast majority of the casings -- cartridge casings you recovered were .40 caliber?
DAVID CAHILL: Yes.
MR. WATKINS: And that's understandable. That's kind of standard issue for police departments. Many police departments use .40 caliber, right?
DAVID CAHILL: Yes.
MR. WATKINS: Some upgrade to .45 caliber?
DAVID CAHILL: Yes.
MR. WATKINS: But in this case, 176 of these cartridges were .40 caliber; only 18 were .45 caliber, right?
DAVID CAHILL: Yes.
MR. WATKINS: And again, these were all cartridges that you matched up to law enforcement weapons, right?
DAVID CAHILL: Yes.
MR. WATKINS: There were also 16 rifle cartridges, right?
DAVID CAHILL: Yes.
MR. WATKINS: 5.56 mm, right?
DAVID CAHILL: Yes.
MR. WATKINS: So there was -- somebody down there actually was able to get their rifle out and fire?
DAVID CAHILL: No, that scene was several blocks away. Those weren't recovered at the Dexter and Laurel scene.
MR. WATKINS: That was four blocks away, on a kind of separate incident of law enforcement, right?
DAVID CAHILL: Yes.
MR. WATKINS: So from the Dexter and Laurel scene, those .40 and .45 caliber, those were all collected, all law enforcement and all at the scene, right?
DAVID CAHILL: Yes.
MR. WATKINS: And more specifically, looking at Exhibit 775, those cartridges were found in this area, right?
DAVID CAHILL: A good number of them were, yes.
MR. WATKINS: I'm sorry?
DAVID CAHILL: A good number of them were. Not all of them.
MR. WATKINS: A good number. Well, some of them were found maybe a little further over here to the right, which is where the Watertown officers were shooting, right?
DAVID CAHILL: Correct.
MR. WATKINS: But there were quite a number found in these areas. Is that right?
DAVID CAHILL: Yes.
MR. WATKINS: And because you had access to the law enforcement weapons and you had access to who submitted those weapons, you got a pretty good idea of who was shooting from where based on the cartridges, right?
DAVID CAHILL: Yes.
MR. WATKINS: We don't know, because as a cartridge we don't know which direction they're shooting, but you know generally where they were standing when they were shooting, correct?
DAVID CAHILL: Yes.
MR. WATKINS: So, for example, taking this northeast corner here, you're able to identify five different weapons that were firing from that northeast corner. Is that correct?
DAVID CAHILL: Yes.
MR. WATKINS: A Watertown Police Department officer was firing from there?
DAVID CAHILL: Yes.
MR. WATKINS: Four Boston Police Department officers were firing from that northeast corner, right?
DAVID CAHILL: Yes.
MR. WATKINS: And over on this side we have three Boston Police Department officers firing from that side, right?
DAVID CAHILL: Yes.
MR. WATKINS: And one Massachusetts state trooper firing, right?
DAVID CAHILL: Yeah, he was a little farther down the street but in that general area.
MR. WATKINS: I'm sorry?
DAVID CAHILL: He was a little farther down the street, but, yes.
MR. WATKINS: Again, generally -- I mean, you can point to it if you --
DAVID CAHILL: He was farther down.
MR. WATKINS: Oh, I see. To the left there.
DAVID CAHILL: Yes.
MR. WATKINS: But he was in that general area there, right?
DAVID CAHILL: Yes.
MR. WATKINS: And down here also officers firing. There would be Dic Donohue, from whom we heard from.
DAVID CAHILL: He was -- I don't believe Officer Donohue fired his weapon.
MR. WATKINS: Officer -- a Cambridge Police Department officer and two Watertown Police Department officers firing from that direction?
DAVID CAHILL: Yes, sir.
MR. WATKINS: Now, you also were -- you were able to collect projectiles from a Mercedes SUV?
DAVID CAHILL: Yes, we were.
MR. WATKINS: I'm putting before you what's been admitted as Exhibit 339. Is that the Mercedes SUV that you collected spent projectiles from?
DAVID CAHILL: Yes.
MR. WATKINS: And showing it from another angle, which is Exhibit 3044, that is the left side of it, correct?
DAVID CAHILL: Yes.
MR. WATKINS: And from inside of the Mercedes -- or embedded in the Mercedes itself were 32 spent projectiles. Is that correct?
DAVID CAHILL: Yes.
MR. WATKINS: Let me go back again to -- oh, and again, were you able to match these to law enforcement weapons?
DAVID CAHILL: No, I was not.
MR. WATKINS: Going back again, then, to Exhibit 775, when you were collecting evidence you were aware that a vehicle had been reported fleeing in that direction through this intersection, correct?
DAVID CAHILL: Yes.
MR. WATKINS: And what you found embedded in the Mercedes was consistent with that and consistent with where you knew officers to be, right?
DAVID CAHILL: Yes.
MR. WATKINS: So to state the obvious, I guess, the officers were shooting at the Mercedes as it was going by?
DAVID CAHILL: Correct.
MR. WATKINS: There were also bullets through the windshield that you saw in that Mercedes, but there were holes in the side -- either side, correct?
DAVID CAHILL: Yes.
MR. WATKINS: So we've heard evidence about Officer Donohue being injured in this -- or this vicinity.
DAVID CAHILL: Uh-huh. That vicinity.
MR. MELLIN: Your Honor, objection to this line of questioning at this point. This is speculation. This is a firearms' examiner who's talking about the casings that were recovered and making identifications of the weapons.
THE COURT: Overruled. I'll allow it.
BY MR. WATKINS:
MR. WATKINS: So again, you've testified about officers having shot from this direction, and we've heard about Dic Donohue being in this area on this driveway, and the Mercedes fleeing in this direction.
MR. MELLIN: Your Honor, objection as to where counsel just says there's been testimony as to where Mr. Donohue was -- Officer Donohue was at the time. He has two different arrows, there's two different locations.
THE COURT: No, I think...
MR. WATKINS: I've taken it off, your Honor.
THE COURT: All right.
BY MR. WATKINS:
MR. WATKINS: Four officers in that area -- sorry -- five officers in that area shooting at a fleeing vehicle. Certainly if one of them missed, you would expect to find a projectile in this area here.
DAVID CAHILL: Is that a question?
MR. WATKINS: It is.
MR. MELLIN: Objection, your Honor. It's complete speculation.
THE COURT: Yeah, I think it is. Sustained.
MR. WATKINS: I have nothing further.
REDIRECT EXAMINATION BY MR. MELLIN:
MR. MELLIN: Lieutenant Cahill, are you always able to find the casings at a crime scene?
DAVID CAHILL: No.
MR. MELLIN: Why is that?
DAVID CAHILL: They could be lost; a vehicle could drive through the scene, get caught in the tire and leave the scene; people pick them up as souvenirs sometimes.
MR. MELLIN: Right. So if a car is driving down Laurel Street, they could run over one of these casings, and these casings become embedded in the tire, correct?
DAVID CAHILL: Correct.
MR. MELLIN: All right. Now, we talked a little bit about bullets in a windshield. Did you also look at bullets in another car and into a windshield?
DAVID CAHILL: There were two Watertown cruisers that we --
MR. MELLIN: What did you determine about that?
DAVID CAHILL: That one of the 9 mm rounds from the weapon was recovered from the Watertown cruiser.
MR. MELLIN: And when we're saying "one of the 9 mm rounds," we're talking about the weapon that you recovered on the scene. Is that right?
DAVID CAHILL: Yes.
MR. MELLIN: And you recovered the spent projectile inside that Watertown police car, correct?
DAVID CAHILL: Yes.
MR. MELLIN: And it was shot through the windshield?
DAVID CAHILL: Yes.
MR. MELLIN: And it was tied back to that gun?
DAVID CAHILL: Yes, it was.
MR. MELLIN: Thank you. Nothing further.
MR. WATKINS: Nothing.
THE COURT: All right, Lieutenant. Thank you. You may step down.
DAVID CAHILL: Thank you, your Honor.
(The witness is excused.)
MR. WEINREB: The United States calls Agent Matthew Riportella.