Speaker 1: Brought to you by the reinvented two thousand twelve camera.
Speaker 1: It's ready. Are you get in touch with technology? With
Speaker 1: tech stuff from how stuff works dot com. Hello everyone,
Speaker 1: and welcome to text stuff. My name is Chris Polette
Speaker 1: and I'm an editor at how stuff works dot com.
Speaker 1: Sitting across from me as usuals who wants to start
Speaker 1: off this podcast with a bang is senior writer Jonathan Strickland.
Speaker 1: Samuel Spade's jaw was long and bony, his chin jutting
Speaker 1: v under the more flexible V of his mouth. Very nice,
Speaker 1: Thank you. You know we did a podcast on nuclear
Speaker 1: weapons recently, Yes, we did, um, and right in the
Speaker 1: middle of it, for reasons that I can't even fathom,
Speaker 1: I started thinking about other kinds of weapons, and I thought,
Speaker 1: you know what, it would be kind of interesting to
Speaker 1: do a podcast on ballistics, which is basically the science
Speaker 1: of figuring out moving stuff and projectiles. Yeah, yeah, I
Speaker 1: I was. I agree, that was a cool idea. Yeah,
Speaker 1: it's a science of deals with motion of projectiles. But
Speaker 1: of course it's been used. Sorry, I didn't mean an interrupt.
Speaker 1: I was gonna say that, you know, ballistics, it also
Speaker 1: is kind of shorthand for a specific branch of forensics,
Speaker 1: which is really what we're focusing on today. Yes, because
Speaker 1: when you get down to it, the actual study of
Speaker 1: ballistics is in large part a matter of physics. Yes. Yes,
Speaker 1: there's a lot of science involved in this. We know
Speaker 1: how we much we hate science, dad gum it um.
Speaker 1: Unfortunately for the scientists, but fortunately for crime mystery writers.
Speaker 1: Bullets do not always behave themselves in terms of physics, Like,
Speaker 1: they generally go where they're supposed to go, but they
Speaker 1: don't always follow the normal path when they get there. Yeah,
Speaker 1: let's just say that it's all due to little, tiny
Speaker 1: individual differences on a very small scale. Because we don't
Speaker 1: mean to say that bullets somehow defy the laws of physics. No,
Speaker 1: but they don't always. They don't always travel like a
Speaker 1: predictable path. Right. You might think, oh, well, if so
Speaker 1: and so was standing here and shot such and such
Speaker 1: over there, then the bullets should be right here. That's
Speaker 1: that's not always the case. Even even saying the cartridge
Speaker 1: for the the case for the cartridge should be right here,
Speaker 1: that's not always the case either. So to really understand this,
Speaker 1: first of all, we need to talk a little bit
Speaker 1: about how the forensics part of ballistics all came about
Speaker 1: in the first place. Yes, and and really ballistics people
Speaker 1: have been trying to get the science behind uh forensics
Speaker 1: ballistics down for quite some time, but it hasn't really
Speaker 1: been that long that we really got it down pat.
Speaker 1: I mean in the nineteenth century, Uh, there were people
Speaker 1: who were trying to figure out how to do this,
Speaker 1: but they were the methods they were using were not
Speaker 1: at all scientific, right, And to understand how you would
Speaker 1: be able to use ballistics to try and identify a
Speaker 1: weapon that fired a particular projectile, you have to understand
Speaker 1: a little bit more about what goes on with these projectiles.
Speaker 1: So sometime around oh, the late fifteen century, the people
Speaker 1: who were creating firearms at that time discovered something which
Speaker 1: was that if you were to have a barrel of
Speaker 1: a weapon have some grooves in it to help direct
Speaker 1: the projectile to spin as it comes out of the barrel,
Speaker 1: you improve the stability of that projectile's flight path. Yeah.
Speaker 1: Previously they were what you call smooth bore, which was
Speaker 1: basically a a smooth tube. The inside of it was smooth,
Speaker 1: so you would, uh, you know, say, take your musket
Speaker 1: and fire, uh, fire a shot from it. Um. Actually,
Speaker 1: you know this is this is I was getting ready
Speaker 1: to dismiss this in my head, but I think we
Speaker 1: should mention this. Um. You know those early muskets where
Speaker 1: you would you know, uh, you'd have to get everything ready.
Speaker 1: You'd have to put the wadding and the and the
Speaker 1: powder in and then the musket ball and tamp it
Speaker 1: all down with the rod before you could fire the weapon.
Speaker 1: You know, whether it's matchlock or flint lock, which we
Speaker 1: talked about in another podcast. Um, but you have a
Speaker 1: basically a roundsh ball made of lead which is fired
Speaker 1: using um, the explosive gunpowder and the the gases propelled
Speaker 1: the ball out of the tube and you know they go, well,
Speaker 1: they go where they go generally go in the direction
Speaker 1: that the barrel was pointing. Yes, more specific than that, Yeah,
Speaker 1: it h They weren't nearly as accurate as a rifled barrel,
Speaker 1: which is what which is what Jonathan was just talking about,
Speaker 1: where the there are grooves inside the barrel and they
Speaker 1: are UM and they travel in a spiral pattern. I
Speaker 1: remember correctly, didn't we talk about something in the rim
Speaker 1: when they started grooving the barrel? But they weren't They
Speaker 1: weren't in a spiral pattern. They were straight m may
Speaker 1: have been I can't remember, I'm sorry, But eventually they
Speaker 1: did hit onto the fact that a helical groove spiral
Speaker 1: groove would uh where where that would create enough spend
Speaker 1: so that the projectile would become much more stable. Of like,
Speaker 1: this is the same sort of idea you get when
Speaker 1: you have a football player throwing a football American football.
Speaker 1: American football player, um your hands. You know when you
Speaker 1: hear about like when you hear about like a tight
Speaker 1: spiral that helps that projectile in this case the American
Speaker 1: football maintain a precise flight path. Well, while that was
Speaker 1: very useful in making firearms more accurate, it was not
Speaker 1: the out of as a way of identifying a firearm
Speaker 1: based upon a projectile that had been fired for several centuries.
Speaker 1: It wasn't until the eighteen hundreds and uh actually I
Speaker 1: have the earliest this. This is all from a website
Speaker 1: called Firearms I d and it was created by a
Speaker 1: guy named Scott Doyle who did some amazing research on ballistics,
Speaker 1: the history of it, and all of the elements that
Speaker 1: go into identifying firearms. If you are interested in the subject,
Speaker 1: I recommend you check out firearms, I d because it
Speaker 1: is truly exhaustive. I'm only going to give a small
Speaker 1: fraction of what he made available. So the earliest of it,
Speaker 1: he found the earliest documented case of identifying a firearm
Speaker 1: UH in a criminal case happened in eighteen thirty five
Speaker 1: in London. And what had happened was a homeowner was
Speaker 1: killed by by a gun and a servant was suspected
Speaker 1: of being the perpetrator. And UH, a fellow named Henry
Speaker 1: Goddard UM who was with the London Police or with
Speaker 1: a branch of the London Police, was assigned the case.
Speaker 1: And he examined the the the projectile that killed this
Speaker 1: shop owner and determined that it was made by a
Speaker 1: particular mold um by UH, which meant that it came
Speaker 1: from a specific company. And then he looked at the
Speaker 1: paper patch that was used in the the the firing
Speaker 1: as well. Now, this paper what it did was it
Speaker 1: created a seal between the powder and the projectile so
Speaker 1: that when the powdering knights and the gases expand, the
Speaker 1: projectile would have a good seal on it, so it
Speaker 1: would it would fly out properly. And you saw that
Speaker 1: this paper patch had been made from some newspaper that
Speaker 1: had been in the room. He actually found the page
Speaker 1: where the newspaper had been torn to make that patch,
Speaker 1: and so they were able to determine that it was,
Speaker 1: in fact the servant who appeared to have fired on
Speaker 1: this shop owner. And so that was the first case.
Speaker 1: Now in that case, it wasn't an idea, you know,
Speaker 1: specifically checking the bullet for the spiral marks that would indicate, um,
Speaker 1: what gone fired it, because that's that's something else we
Speaker 1: should mention, these rifling marks. Uh. In fact, that's why
Speaker 1: we call it a rifle. There's these rifling marks that
Speaker 1: are on the bullet itself. That's that's caused. As a
Speaker 1: bullet travels down this this grooved barrel, it cards little
Speaker 1: scratches into the bullet. And so these scratches are unique
Speaker 1: to a particular weapon. Even even two weapons of the
Speaker 1: same make and model will produce different scratches, at least
Speaker 1: on a on a tiny let. You know, beyond a
Speaker 1: superfluous glance, you'll be able to see that there are
Speaker 1: different prances, and so it's almost like a fingerprint. If
Speaker 1: you are able to see, you know, tell that two
Speaker 1: different bullets are close enough and identity that these these
Speaker 1: markings are really really you know, to all intentsive purposes, identical.
Speaker 1: You can say that they were both fired by the
Speaker 1: same weapon. So if you happen to have that weapon
Speaker 1: in your possession and you've done a bunch of test
Speaker 1: firings and all the bullets are coming out the same
Speaker 1: way and they matched the bullet that was used in
Speaker 1: a crime, you can feel pretty confident saying that that,
Speaker 1: in fact was the weapon that was used in that crime. Um.
Speaker 1: So yeah, I mean there, um, there are many cases
Speaker 1: in which you know, this has been this has been used.
Speaker 1: I mean one of the first I read, and I
Speaker 1: read an excellent article by Katherine Ramsland um in uh
Speaker 1: in which he was talking about do you remember learning
Speaker 1: about Sacco and Vanzetti in your American history class? This
Speaker 1: very controversial, absolutely absolutely. Um. This was a case in which, uh, um,
Speaker 1: the payroll was being delivered to a shoe factory and
Speaker 1: a a couple of guys came up and shot the guards,
Speaker 1: and um, you know, they basically made off with the money,
Speaker 1: and uh so they started looking for information. This, by
Speaker 1: the way, was April fifty, um, and this is when
Speaker 1: they started looking. Uh. This really was the incident that
Speaker 1: made modern ballistics a science, I think, UM, just from
Speaker 1: from the way they handled it. So UM, the investigators
Speaker 1: behind this UH collected all the evidence they could, including
Speaker 1: the spent shell casings. UM. They went back to looking
Speaker 1: at the manufacturers of of weapons. UM. There were about
Speaker 1: six at the time that they looked at, and UH
Speaker 1: they turned out to be Remington, Winchester, and Peters UM
Speaker 1: that that could use these these casings UM. And what
Speaker 1: they what they ended up doing was they started, uh,
Speaker 1: you know, looking around at you know, what they could
Speaker 1: get from this information. And as it turns out, one
Speaker 1: of the incriminating factors was the fact that for one
Speaker 1: of the weapons that they had, the only bullets that
Speaker 1: they could find, uh that would fit that weapon were
Speaker 1: in Saco's pocket. UM, which is pretty incriminating evidence, but
Speaker 1: it's not exactly that's circumstantial, you know. UM. So what
Speaker 1: they did was they talked to somebody who had worked
Speaker 1: with UH sort of preliminary ballistics technology. His name was
Speaker 1: Albert H. Hamilton's and UH he actually had been um
Speaker 1: working with UH with other cases and UH he wasn't
Speaker 1: completely scientific um in his methods, but he he actually
Speaker 1: got stuck in the middle of the case. And during
Speaker 1: this uh the Sacco and Vanzettie case, UM came in
Speaker 1: with new weapons that were UH similar to the ones
Speaker 1: that they had and basically disassembled them in front of
Speaker 1: the judge who noticed that he was swapping parts with
Speaker 1: the other gun and went, no, you can't do that,
Speaker 1: and they threw it out. But they did give the
Speaker 1: information to Calvin Goddard, someone who is quite famous in
Speaker 1: ballistics forensics. Yeah, he's he's I would argue that he's
Speaker 1: probably considered by many people to be the father of
Speaker 1: this technology. He worked with a guy named Charles Waite
Speaker 1: at in New York with the Bureau of Forensic Ballistics,
Speaker 1: and he was using microscopes and a helixometer, which is
Speaker 1: a probe that you could use to look at gun
Speaker 1: barrels UM. I imagine that was used in the manufacturing
Speaker 1: of these weapons. UM. But what he did was he
Speaker 1: fired these the weapons used or or in Sacco and
Speaker 1: Vanzetti's possession, UM into a wad of cotton and compared
Speaker 1: the casing and the bullet to the ones recovered in
Speaker 1: the investigation. And they were similar enough UM to incriminate
Speaker 1: both of them. Now um, Vanzetti, I mean, they put
Speaker 1: both of them to death, but Vanzetti said he was innocent,
Speaker 1: and uh apparently Zacho's uh last words were long live anarchy,
Speaker 1: which doesn't exactly uh he he doesn't exactly say, well,
Speaker 1: you know, I didn't do any of that, but yeah,
Speaker 1: and and in later years too, they've still they continue
Speaker 1: to examine that and uh, right now, although it's still
Speaker 1: controversial whether or not these guys were railroaded or whether
Speaker 1: or not they actually did commit the crime. Um, uh,
Speaker 1: they still say that. Uh, the weapons still support Goddard's
Speaker 1: findings even years later. So the technology we're using now
Speaker 1: suggest that those weapons were the ones used them. That
Speaker 1: Bureau of Forensic Ballistics was formed in in April nineteen
Speaker 1: twenty five in New York City, and the whole purpose
Speaker 1: behind it was that by nine you remember, back in
Speaker 1: eighteen thirty five, was the first time we see someone
Speaker 1: trying to identify a firearm, uh, after a crime has happened.
Speaker 1: The firearm itself was the one that was used. By
Speaker 1: ninety five, there had been a lot of pioneers who
Speaker 1: worked on this idea of identifying firearms based upon the
Speaker 1: projectiles they fired, and uh, The problem was that the
Speaker 1: the resources were scattered, right. I mean you had you
Speaker 1: had some communities that might have an expert that resides
Speaker 1: within that community, but then you know, you might have
Speaker 1: hundreds of miles of area where there is no expert,
Speaker 1: there's no one to call upon. And so the Bureau
Speaker 1: was formed as a resource for law enforcement agencies across
Speaker 1: the United States. There were other countries that were doing
Speaker 1: similar things. Actually, a lot of this early research where
Speaker 1: the idea was, hey, look, they're these markings on this bullet.
Speaker 1: They're consistent with every bullet that's fired from this particular gun,
Speaker 1: and they're different from all the ones that are fired
Speaker 1: from that gun. That kind of work was being done
Speaker 1: all over the world. In fact, there were a lot
Speaker 1: of people in France who wrote a lot of instrumental
Speaker 1: early papers on identifying firearms based upon their projectiles or Yeah.
Speaker 1: And then two, the FBI, the Federal Bureau of Investigation
Speaker 1: here in the United States was directed by a their
Speaker 1: jaunty head of staff, Jagger Hoover. I think that's the
Speaker 1: first time I've ever heard is I think that's what
Speaker 1: Jay stands for, right, John T. Edgar Hoover. Um, No,
Speaker 1: not at all, uh, he know, it was more like,
Speaker 1: really you said that, really it was a question mark,
Speaker 1: like the sarcastic kind. It wasn't actually an interrobang, gotcha.
Speaker 1: So he directed that the FBI should create a lab
Speaker 1: for ballistics forensics as well, and so this was becoming
Speaker 1: really serious business. And then we're there were a lot
Speaker 1: of early cases between you know, the late eighteen hundreds
Speaker 1: and and nineteen twenty that established that this was a
Speaker 1: legitimate means of investigation. So let's talk a little bit
Speaker 1: more about what you actually do when you're trying to
Speaker 1: identify whether or not a particular bullet was fired from
Speaker 1: a particular gun. First of all, it helps if we
Speaker 1: if we talk about bullets and cartridges because we and
Speaker 1: we've done this in another podcast, but it always helps
Speaker 1: because a lot of I think people who are generally
Speaker 1: unfamiliar with guns don't know the anatomy of a gun. Yep.
Speaker 1: And that's part of why I wanted to mention that
Speaker 1: about the muskets Um because you know, after a while
Speaker 1: they realized that the system that we're about to talk about,
Speaker 1: it makes the weapons much more reliable using those things
Speaker 1: and faster to operate because rather than having to put
Speaker 1: the powder in the in the wadding and all that
Speaker 1: stuff in there, and and prepare the weapon to be fired.
Speaker 1: I mean, I saw I can't even remember what show
Speaker 1: it was. I saw a thing on TV where they
Speaker 1: had somebody firing and must get as fast as they could,
Speaker 1: just to see how quickly a trained um musketeer could
Speaker 1: fire a weapon. It's about three times per minute. Three
Speaker 1: times per minute is considered an excellent time. Yeah, I know,
Speaker 1: I've seen I've seen artillery cruise that we're using, uh
Speaker 1: period cannon's um Actually it wasn't a cannon, but anyway,
Speaker 1: it was. It was an artillery gun, period artillery gun.
Speaker 1: And they talked about how even with a well trained
Speaker 1: group of troops who were familiar with the weapon, three
Speaker 1: times a minute was considered to be the peak performance.
Speaker 1: So one of the biggest innovations was the idea of
Speaker 1: why don't we take the system of gunpowder and wadding
Speaker 1: and shot and all that, and why don't we try
Speaker 1: and figure out a way of packaging it all into
Speaker 1: one thing that you load into a gun once and
Speaker 1: then you fire. So instead of having to load in
Speaker 1: all these separate pieces and pack them together and hope
Speaker 1: that it fires correctly. It's all packaged together there, and
Speaker 1: that's the idea behind the cartridge. In fact, the earliest
Speaker 1: cartridges were these little paper cartridges that had everything packed together,
Speaker 1: and uh, they were used in the Civil War mainly.
Speaker 1: But then actually that was sort of the step between
Speaker 1: where you put the cartridge in and then and then
Speaker 1: the musket ball right right the shot. Yeah, the cartridge
Speaker 1: contained essentially all the stuff that you would have put
Speaker 1: in previously besides the shot itself. Well, the modern day
Speaker 1: cartridges have the the fuel that's going to push the
Speaker 1: the bullet forward and the bullet itself all packed together.
Speaker 1: So you've got a case that's typically made out of
Speaker 1: something like brass or maybe steel, depends on the particular manufacturer,
Speaker 1: and the ammunition involved pretty typically brass, and then you
Speaker 1: have a bullet at the end. The bullet is the
Speaker 1: actual projectile that will fire out of the gun. The
Speaker 1: case remains behind. Now, the case also contains it contains powder,
Speaker 1: primer and a primer mix and uh, and that's the
Speaker 1: stuff that when a firing pin from the weapon hits
Speaker 1: the primer, that ignites the primer, which then in turn
Speaker 1: ignites the powder which creates this massive amount of gas.
Speaker 1: Massive in a relative term, I should say um amount
Speaker 1: of gas within the case. That's what pushes that that
Speaker 1: bullet out of the weapon. So the case remains behind.
Speaker 1: The case is actually altered by this because the gases
Speaker 1: are pretty hot. Then they pushed pretty hard, so the
Speaker 1: case itself will change a little bit. Then you have
Speaker 1: to extract the case from the weapon and put a
Speaker 1: new cartridge in its place in the chamber of the
Speaker 1: weapon in order to fire it again. And of course
Speaker 1: we've also talked about machine guns. So if you're talking
Speaker 1: about an automatic weapon, you put in you have a magazine,
Speaker 1: some feeding mechanism, feeding mechanism that will automatically pop the
Speaker 1: next it will pop the spent cartridge out of the
Speaker 1: weapon and uh load the next cartridge in and ready
Speaker 1: to be fired. And it happens very very quickly. So
Speaker 1: but it operates on the same same principle. So here's
Speaker 1: the interesting thing, a couple of interesting things. First of all,
Speaker 1: we talked about the rifling with the grooves within the
Speaker 1: barrel which are going to cut into the bullet, making
Speaker 1: a fingerprint on that bullet, so that if you were
Speaker 1: to find two bullets fired by the same gun, and
Speaker 1: you were to compare them side by side, you should
Speaker 1: be able to see the same markings on both because
Speaker 1: it's it's going to carve it out the same way. Well,
Speaker 1: the same sort of thing goes plays for the cartridge
Speaker 1: or like the case, rather for the cartridge. Um, the case,
Speaker 1: the spent cartridge is going to have some markings on
Speaker 1: it as well. Um, some of it maybe scratches just
Speaker 1: from you know, the way that it sits in the chamber,
Speaker 1: or if the there if there's an extractor, if there's
Speaker 1: an actual mechanical element in there that kicks that spent
Speaker 1: cartridge out, that can leave a mark on the case
Speaker 1: as well. So that way, if you don't maybe you
Speaker 1: don't even have the bullets, maybe you just have the
Speaker 1: spit cases, you can compare those and see. So I
Speaker 1: Step one of identifying the weapon is identifying what caliber
Speaker 1: of bullet was used and you know what kind of
Speaker 1: cartridge was used, because that will limit the type of
Speaker 1: weapons that could have fired that particular ammo, right, because
Speaker 1: not every gun fires every immunition. Because anyone who has
Speaker 1: ever worked with guns nose they're very specific kinds of
Speaker 1: ammo that work with particular guns and you cannot you
Speaker 1: cannot interchange them. Nope, nope. UM. And uh you know
Speaker 1: each each weapon Now, each manufacturer when they make when
Speaker 1: they put the grooves in there and the the section between. UM.
Speaker 1: Basically the ridges around the grooves are called lands. UM.
Speaker 1: Those metal ridges basically are what helped the bullet reach
Speaker 1: its destination by providing it the spin and accuracy. UM.
Speaker 1: But they also are are uh common to manufacturers. So
Speaker 1: one weapons manufacturer might put six grooves in the barrel,
Speaker 1: one might use four. UM. So one of the things
Speaker 1: these marks left and they are unique to every weapon. UM.
Speaker 1: These marks are going to help the forensics investigator if
Speaker 1: if if they can find the bullets, they're going to
Speaker 1: be able to identify which manufacturer made the gun. That
Speaker 1: will help track it down. And then from there they
Speaker 1: can look at other things that will help them at
Speaker 1: least narrow down. He said, well, this couldn't have been uh,
Speaker 1: this couldn't have been the gun that fired because it's
Speaker 1: not even the same manufacturer. It's not the right people.
Speaker 1: So we can rule this out. From there, they can
Speaker 1: look at specific guns because multiple manufacturers can make the
Speaker 1: same type of gun. Yes, so yeah, so narrowing it
Speaker 1: down to your First you look at the caliber of
Speaker 1: the bullet, uh and the case so that you can
Speaker 1: determine what kind of m O was used. That narrows
Speaker 1: it down to a range of weapons that might be
Speaker 1: able to fire that looking at the actual pattern on
Speaker 1: the bullet itself and uh, well we'll give you at
Speaker 1: least an idea of the specific type of weapon used
Speaker 1: and the manufacturer. And then again comparing that bullet with
Speaker 1: one like a test bullet fired from a weapon will
Speaker 1: let you know if it's fired from the same weapon.
Speaker 1: So you're you keep narrowing it down. This is very scientific.
Speaker 1: I mean you're talking about going from the general to
Speaker 1: the very specific, and so you're just eliminating all the
Speaker 1: other options until what you're left with is the only,
Speaker 1: hopefully the only uh possible answer. And um, there are
Speaker 1: a lot of different ways that that these the cartridges
Speaker 1: can have marks on. Besides the ejection UM mark, there
Speaker 1: could be firing pen marks, so you can see how
Speaker 1: the firing pin struck the bottom of the cartridge. That
Speaker 1: will tell you a lot about the type of weapon.
Speaker 1: Like there's certain weapons that have a very distinct firing
Speaker 1: pen mark, So like a square one a good indicator
Speaker 1: that that was a glock that fired the weapon. And
Speaker 1: there are certain marks that are you're going to find
Speaker 1: that are common to particular types of weapons, So forensics
Speaker 1: experts will use that when they're actually examining UM bullets.
Speaker 1: So let's let's say there's a there's a crime case.
Speaker 1: Let's make this more specific, there's a crime case in
Speaker 1: which someone was shot UM and the police have recovered
Speaker 1: a weapon from a suspect. They do not know if
Speaker 1: the weapon is the one that was used in the crime.
Speaker 1: They do know that it matches the same UM model
Speaker 1: and maker of the weapon that was used in the crime.
Speaker 1: But that's all I know. The forensics expert what they
Speaker 1: will do is they'll take the gun. Uh, They'll take
Speaker 1: possession of the gun that's from the suspect, and they'll
Speaker 1: fire it into a water tank. And the water tank
Speaker 1: is a long tank of water several and it's usually
Speaker 1: around ten feet long. It's got about three ft wide
Speaker 1: three ft high full of water. And on one end
Speaker 1: of this water tank, which is sealed on all sides,
Speaker 1: which is important you don't want any stray bullets flying out,
Speaker 1: there's a hole through one side a tube where you
Speaker 1: can fire through that tube, it goes into the water.
Speaker 1: The water is meant to slow down the progress of
Speaker 1: the bullet, and as it slows down, it'll come to
Speaker 1: arrest at the bottom of the tank. You the forensics
Speaker 1: expert will retrieve that bullet, and then they take that
Speaker 1: bullet and the bullet used in the crime, assuming they've
Speaker 1: recovered a bullet, because otherwise there's no point in doing this.
Speaker 1: So they've recovered a bullet from the crime itself. You
Speaker 1: put that and the test bullet or several test bullets
Speaker 1: into a macroscope, a comparison macro scope, and you might think, hey, Jonathan,
Speaker 1: what's a macroscope, I've heard of microscopes. Well, macroscope is
Speaker 1: it's it's a device that does magnify things, but it
Speaker 1: usually magnifies them by a pretty small multiplier compared to
Speaker 1: a microscope. You know, microscopes you're talking about multiplying magnifying
Speaker 1: something by a hundred times or more. Macroscopes tend to
Speaker 1: be five, ten, maybe twenty times, so it's not it's
Speaker 1: not giving you that incredibly up close look that a
Speaker 1: microscope would. It's called a comparison macroscope because you can
Speaker 1: actually put in two different items. So in this case,
Speaker 1: you put the bullet from the crime and the bullet
Speaker 1: from the test, uh onto the little platform it actually
Speaker 1: and here's there with some sticky stuff some some you know,
Speaker 1: it's essentially glue, um, and then you put it through
Speaker 1: the microscope. The microscope directs the images up to the
Speaker 1: viewfinder where you look in and you can actually see
Speaker 1: side by side the two projectiles, so it looks like
Speaker 1: it looks like they are you know, right next to
Speaker 1: each other, even though they're actually on two different little
Speaker 1: platforms on the macroscope itself, and it allows you to
Speaker 1: take a really close could compare those markings at a
Speaker 1: a nice magnified level to determine whether or not they
Speaker 1: are identical, or whether or not the markings are identical. Obviously,
Speaker 1: the bullets can't be yeah, because someone is probably saying, yeah,
Speaker 1: but Jonathan, why do they have to fire it into
Speaker 1: a water tank? I mean, why couldn't they just you know, uh,
Speaker 1: go to the crime scene and shoot it off the
Speaker 1: wall and see what happens. Well for one thing, of course,
Speaker 1: again you don't want stray bullets. But um, you know,
Speaker 1: I don't know if any if a lot of people
Speaker 1: know that. I mean it probably his common sense when
Speaker 1: you think about it. But bullets the forms quite a
Speaker 1: bit in the process of firing them. UM. Actually, I
Speaker 1: remember UH my rifle recourse at camp when I was
Speaker 1: a kid. UM. Every once in a while, UH, the
Speaker 1: instructor would take us down to the end of the
Speaker 1: range and there was a big pile of dirt there.
Speaker 1: So the bullets would go through the targets and hit
Speaker 1: the dirt and stopped there. So we would go in
Speaker 1: and dig some of them out and they would come
Speaker 1: out in the oddest shapes. The thing is, UM, you
Speaker 1: want the bullet to be identifiable enough so that you
Speaker 1: can really see the markings on it. UM. And shooting
Speaker 1: it against something else that will catch it. UH. You know,
Speaker 1: it will also be deformed by the impact if the
Speaker 1: water slows it down and it basically just drops to
Speaker 1: the bottom of the tank. Once it it's more forward
Speaker 1: momentum stops. UM, then it's going to be much less
Speaker 1: affected by the impact of of uh its landing and
Speaker 1: UM then you can get a good idea of what
Speaker 1: it's actually going to look like in the marks that
Speaker 1: are on it and and sometimes the bullets retrieved from
Speaker 1: crime scenes are in really bad shape. I mean because
Speaker 1: they've they've gone through various materials, especially if you know
Speaker 1: they maybe hit like a door frame or something or
Speaker 1: you know whatever. Uh, And it can be a challenge
Speaker 1: to identify them just because the bullets themselves may not
Speaker 1: be indecent enough shape for you to be able to
Speaker 1: make a good comparison. But this is to try and
Speaker 1: make the the conditions as ideal as possible so that
Speaker 1: you can at least narrow things down. You know, the
Speaker 1: goal really is to see if you can eliminate that
Speaker 1: gun from suspicion, because if you can, then you know
Speaker 1: you're on the wrong track and you can go direct
Speaker 1: your attention elsewhere and not waste time on something that
Speaker 1: ultimately is a dead end. So um yeah, I mean
Speaker 1: that's that's your basic approach. It's kind of interesting, like
Speaker 1: the whole process of developing this. I mean, there were
Speaker 1: there were earlier UH forensics experts who would compare bullets.
Speaker 1: They didn't have the luxury of a comparison macroscope to use,
Speaker 1: so in many cases they were using photography. They would
Speaker 1: take um pictures of these bullets and try and enlarge
Speaker 1: the photographs as large as they could and compare them
Speaker 1: that way, and try and find as many points of
Speaker 1: comparison as they could between the two to determine whether
Speaker 1: or not a bullet was in fact fired by the
Speaker 1: same weapon as another bullet. So again, points of comparison,
Speaker 1: just like with fingerprints, you know, you look for a
Speaker 1: certain number, and if you you figure that if you
Speaker 1: find now uh like a dozen or two dozen points
Speaker 1: of comparison that are identical, the chances of that being
Speaker 1: just coincidence are pretty slim. So that's when you sit
Speaker 1: there and say, no, I'm pretty sure this bullet was
Speaker 1: fired by the same gun as the one that I tested.
Speaker 1: And another thing that that Goddard did along with his partner, um,
Speaker 1: back in the very early days of all this, he
Speaker 1: started they started compiling a database of information about different
Speaker 1: weapons UM, which is, if you think about it, rather
Speaker 1: crucial uh to doing this because it allows you to
Speaker 1: know you know in which direction and which angle a
Speaker 1: particular manufacturers uh lands are going to show up inside
Speaker 1: the barrel. UM helps you eliminate you know, they can
Speaker 1: look at a bullet and go, oh, well, I know
Speaker 1: that it's not this or this or this or this,
Speaker 1: and by the scientific method, I've at least narrowed it
Speaker 1: down to one manufacturer and from there, you know, and
Speaker 1: and having all that information in a database and comparing
Speaker 1: the weapons and I'm sorry, the bullets side by side,
Speaker 1: it gives you, um the ability to scientifically rule things
Speaker 1: out step by step. And he really created a method
Speaker 1: and a plan for doing this that set the stage
Speaker 1: for what we know as modern ballistics work. Yeah, and
Speaker 1: it's if you read about again, I do urge you
Speaker 1: to check out more information about the progression of of
Speaker 1: keep gathering this information because it goes beyond just comparing
Speaker 1: bullets to each other. The history of forensics is pretty
Speaker 1: fascinating and in some ways sometimes darkly humorous and in
Speaker 1: some cases just bizarre. Like you'll you'll find out about
Speaker 1: people sheriffs who found a victim who had um a
Speaker 1: hole in their shirt and there was suspicion that perhaps
Speaker 1: a a gun had the person had been shot by
Speaker 1: a gun and then a bullet had toward the whole.
Speaker 1: So the sheriff would take the shirt out to a
Speaker 1: firing range and fire bullets into it to see if
Speaker 1: the tears that were made by the bullets were similar.
Speaker 1: To the one that was on the shirt in the
Speaker 1: first place. Well, they can tell um whether a wound
Speaker 1: is an entrance wound or an exit wound somewhat by
Speaker 1: the the type of hole that it leaves. I mean,
Speaker 1: if you're um, right on top of somebody, uh, it
Speaker 1: will um do more damage. If you're firing at somebody
Speaker 1: at point blank range. Um, then if you are farther away.
Speaker 1: But you can tell by the direction of the fabric,
Speaker 1: you know, if it if it's going into the wound,
Speaker 1: then you could see uh generally that it's probably an
Speaker 1: entrance wound. And if the fibers are are spreading outward,
Speaker 1: then it's probably. And it depends on the bullet too.
Speaker 1: Of course, there are bullets that do a lot more
Speaker 1: damage on on one side or another, so that that
Speaker 1: factors into it too. Of course they'll talk about things
Speaker 1: like blood spatter. Um. I have a great story here,
Speaker 1: I want to I want to tell them so all right,
Speaker 1: So in uh in nineteen o three, a fellow named E. J.
Speaker 1: Churchill in London, England, provided testimony uh do testimony that
Speaker 1: regarded an experiment he had performed that involved shooting bullets
Speaker 1: into sheep's skulls. Yeah, so skulls of sheep, not actual sheep.
Speaker 1: At this point that the sheep have already shuffled off
Speaker 1: the wooly mortal coil and their skulls have remained. And
Speaker 1: what had happened was, um, it was all revolving around
Speaker 1: a case where there was a young woman who or
Speaker 1: a woman, I don't know if she was young, actually
Speaker 1: a woman who was shot and killed in Essex, England,
Speaker 1: and uh, they figured that she had been shot by
Speaker 1: a thirty two caliber revolver, and so Churchill took a
Speaker 1: similar revolver with the same sort of ammunition and a
Speaker 1: whole bunch of sheep skulls and started shooting the sheep
Speaker 1: skulls at various distances to determine to kind of compare
Speaker 1: the damage done, to see how far away the shooter
Speaker 1: might have been from the victim by observing, you know,
Speaker 1: the damage done to the sheep skulls, and he came
Speaker 1: to the conclusion that the the revolver was shot somewhere
Speaker 1: between six and twelve inches away from the victim, and
Speaker 1: this was used. This testimony was used in the court case.
Speaker 1: In fact, the the accused suspect was found guilty and
Speaker 1: put to death. So the experiments early on were very practical,
Speaker 1: you know, the idea of we have this one set
Speaker 1: of circumstances, we need to try and recreate it as
Speaker 1: closely as possible to to deter whether or not the
Speaker 1: scenario we have in our mind is actually at all accurate.
Speaker 1: And uh, and you know, like I said, the history
Speaker 1: of forensics is filled with stories that make that one
Speaker 1: seem tame and boring in comparison. Well, and and there
Speaker 1: are others that are oddly similar, um, that make you
Speaker 1: realize that it isn't always exact because um. Ramslin mentioned
Speaker 1: a case that happened in Oklahoma where a robber used
Speaker 1: a three seven magnum and uh, there was a witness
Speaker 1: and he shot her right in the head. I'm just sorry, um.
Speaker 1: And uh what happened was the bullet went into her skull,
Speaker 1: but it traveled around the inside of her skull before leaving,
Speaker 1: and she ended up surviving and testifying against the robber.
Speaker 1: On In another case, Uh, somebody got shot in the
Speaker 1: wrist with a twenty two, which is a much smaller
Speaker 1: caliber bullet um, and the bullet went into a vein,
Speaker 1: traveled into the heart and killed the persons don't always
Speaker 1: do well. And I also think I've even heard of
Speaker 1: people getting shot in the head and the bullet hits
Speaker 1: the skull and doesn't penetrate the skull, but rather goes
Speaker 1: underneath the skin, travels around the skull, and pops out
Speaker 1: the other side without actually penetrating the skull itself. I remember,
Speaker 1: I distinctly remember when I was living in North Carolina,
Speaker 1: a police dog getting shot in the head and that happening.
Speaker 1: It's yeah, uh, yeah, this is getting really much more
Speaker 1: gruesome than I had intended. You don't mean, I don't
Speaker 1: mean for it to be gruesome, but I think it's
Speaker 1: a situation. Well, I mean, the dog, the dog lives. Um,
Speaker 1: it's a it's a situation that shows you that, you know,
Speaker 1: we sort of assume that if you get shot, if
Speaker 1: you get shot in the right place and at the
Speaker 1: bright distance, that you know, they're a few chances that
Speaker 1: you're gonna make it if somebody's doing what they're supposed
Speaker 1: to be or what they intend to do, let's say,
Speaker 1: with the weapon. Um. But bullets don't always behave themselves,
Speaker 1: which is why these ballistic forensics are so important because
Speaker 1: they you know, they've gotten it down to a science,
Speaker 1: so at least you have a better idea of what's
Speaker 1: going on. And we should also point out that that this,
Speaker 1: you know, we've been talking a lot about bullets. Uh,
Speaker 1: the story is completely different if you were to talk
Speaker 1: about things like shotguns. They do not have the rifled barrels.
Speaker 1: So I mean you're firing shot at that point, not
Speaker 1: not a little lots of little balls. Usually occasionally you
Speaker 1: might have a slug shot slug, but at any rate, yeah,
Speaker 1: taser's yeah, totally different story there. But in those cases
Speaker 1: it's that you have to look for different things. You
Speaker 1: can't you know, obviously you can't compare bullets like you
Speaker 1: could with rifled weapons. Um. And in fact, Scott Doyle
Speaker 1: on his site rights, it should be noted that not
Speaker 1: all firearms lead consistent, reproducible marks. But overall, there's been
Speaker 1: my experience that around eighty percent of the firearms that
Speaker 1: I examine produce what is sometimes called a mechanical fingerprint
Speaker 1: on the bullets and cartridge cases that pass through them.
Speaker 1: So it is possible even for you to get a
Speaker 1: gun that, through some reason or another, Uh, the marks
Speaker 1: that come out the end up on the bullets and
Speaker 1: the cartridges are not I'm not reproducible, and it could
Speaker 1: just be that there's, you know, some sort of weird
Speaker 1: faulty part of that gun. You know, it's there's a
Speaker 1: lot of different factors that could that could cause that.
Speaker 1: And in those cases, of course, then you can't you know,
Speaker 1: the ballistics evidence as far as comparing bullets to each
Speaker 1: other is no longer really reliable. You have to rely
Speaker 1: on other kinds of evidence in in that uh, in
Speaker 1: that sort of case, I would be interesting to know
Speaker 1: if any UH law enforcement authorities who have worked with
Speaker 1: forensics and ballistics have are listening to our show, you know,
Speaker 1: so please let us know if you you are, because
Speaker 1: this is interesting stuff, and thank you for the work
Speaker 1: that you do because it makes a difference. Yeah, we
Speaker 1: had some helicopter pilots right in after we did our
Speaker 1: helicopter episode, which was kind of cool. No one offered
Speaker 1: to take me on a trip. It's not a it's
Speaker 1: not criticism, it's just a statement of fact. I think
Speaker 1: he's hinting, even after I said distinctly that that's on
Speaker 1: my bucket list anyway. What I have not had my
Speaker 1: cheerios this morning all right, so we're gonna wrap this
Speaker 1: discussion up anyway. Yeah, that's It's a pretty fascinating form
Speaker 1: of of of forensics, a scientific inquiry really. Um, I
Speaker 1: found it very interesting when I was reading up on it,
Speaker 1: and like I said, the history in particular I found fascinating.
Speaker 1: If you guys have any subjects you would like us
Speaker 1: to tackle in future episodes, you can let us know
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Speaker 1: at the address tech stuff at Discovery dot com and
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