Crime (murder) scene investigation - gun shot residue

Jenbob · Apr 5, 2018

The scenario: a drunk driver crashes into a limo on a lightly traveled road, such that there are no actual witnesses and it's at least several minutes before anyone arrives at the scene. The driver of the limo is killed in the accident, and in the back of the limo is an unconscious woman sitting across from a man who has been shot in the head, both seatbelted in place. There's no gun in the car, but it's clear that the man could not have been shot very long before the accident and that the woman must have been sitting across from him when it happened. There's no indication that anyone else was in the back of the limo before the accident.

The woman won't regain consciousness until after she's been transported to the hospital and examined. The woman has never been convicted of a crime, but she basically comes from a crime family, and she has been suspected/accused of illegal activities more than once in the past, so no one would have any problem believing she is guilty and it would be logical for the cops to suspect her of murdering the guy in the limo considering the way the scene looks. The only problem of course being lack of weapon.

My question is, would the police be allowed to "examine" her and attempt to sample for gun shot residue before she regained consciousness, or would there be instructions to the hospital to do so or to take care of her clothing so that it could be tested later?

jclarkdawe · Apr 5, 2018

At any possible crime scene, EMTs are instructed to save any and all evidence. Any of her clothes would be saved. This would continue automatically at the hospital as a standard protocol.

If the patient is unconscious with a deceased driver from the accident, she would be a rush transport with the only delay being for such treatment as is necessary to ensure her transport will be as safe as possible. Until she is medically stable, they would not test her hands for gunpowder residue.

In the collision scenario you've described, by the time the woman is transported, all anyone would know is that a gun has not been found. The force of a collision resulting in a fatality does a lot of damage to a vehicle. You'll have to search under seats and all the nooks and crannies before you're sure there's no gun in the car. Then you'd have to search all around the car to make sure it didn't get thrown from the car. You're talking a couple of hours of time, at least.

Jim Clark-Dawe

JNG01 · Apr 5, 2018

To avoid a risk of having the evidence suppressed later, the police would have to get a warrant to swab her hands. Good chance they might not even notice that the fatality was from a GSW until sometime later. And, if they did, they'd still have to get a warrant to conduct a search, and the warrant would depend on them being able to articulat probable cause, which would depend on a better understanding of events then they are likely to have for at least the first hour or so. Then, they'd have to get a judge to sign the warrant (tack on another hour or so). So you're looking at a few hours minimum before anyone's going to do anything--and if your character is lights-out that long, she's probably got a serious TBI.

CWatts · Apr 6, 2018

JNG01 said:
So you're looking at a few hours minimum before anyone's going to do anything--and if your character is lights-out that long, she's probably got a serious TBI.

You could easily have her in surgery during that time and the police have to wait for her to come to from anesthesia. I don't know if OR protocols would destroy the evidence, but my guess us that her hands would just be under the drape if they're not injured.

ironmikezero · Apr 6, 2018

Pragmatically speaking, a gunshot residue test can be administered and produce reasonably reliable results up until the subject's hands and lower arms are washed. Even a twenty-four hour delay may not matter, assuming the hands/lower arms are exactly as they were at the suspected time of the shooting. The success rate tends to diminish rapidly if the time factor is further extended, especially if all circumstances are not tightly controlled.

WeaselFire · Apr 12, 2018

Residue tests are also valid on clothing, so if the woman isn't available the clothing could/would be tested.

Jeff

Hunt & Peck · May 4, 2018

An unconscious person cannot give consent, thus a warrant would be needed, just as if a conscious person was refusing consent for the test.

If the passenger was shot in the vehicle, where's the casing from the bullet? Was that disposed of along with the gun?

JNG01 · May 5, 2018

There are a couple of relevant practical considerations, too.

(1) The bullet has to go somewhere. If it didn't stop inside the victim, it will have proceeded into or though whatever was behind him. Apart from residue, the entry wound, wound channel direction, and location of the bullet (whether within or without the victim) will give investigators a lot of information about the location of the shooter relative to the victim

(2) A gunshot in an enclosed space is LOUD. There would be a tangible and painful pressure wave. Everyone in that limo without ear protection almost certainly has permanent hearing damage. So, if you want investigators to think your character was there and might have pulled the trigger, she'll need serious hearing damage.

(3) The "residue" from the gunshot are the residuals and resultants of the burned gunpowder, which (like the bullet itself) ride the wave of expanding gas caused by the powder ignition out of the barrel. In a tightly enclosed space like a car, that residue would get everywhere. Having a concentration of it on one or both hands would be very suggestive, but there's a chance everyone would end up smeared in the stuff.

Just a few other details relevant to the scene.

WeaselFire · May 5, 2018

JNG01 said:
(2) A gunshot in an enclosed space is LOUD. There would be a tangible and painful pressure wave. Everyone in that limo without ear protection almost certainly has permanent hearing damage. So, if you want investigators to think your character was there and might have pulled the trigger, she'll need serious hearing damage.

This isn't completely true. While potentially loud, and possibly casing temporary hearing loss, there is rarely any permanent damage. Plus, there's a large difference between a subsonic .22 caliber round and a magnum 12 gauge round. The actual vehicle will determine a lot of accoustic characteristics, as will the positions of firearms and shooters. There are no absolutes in such situations.

But the OP can use these things to vary the situation, results and suspicions.

Jeff

JNG01 · May 5, 2018

WeaselFire said:
This isn't completely true. While potentially loud, and possibly casing temporary hearing loss, there is rarely any permanent damage. Plus, there's a large difference between a subsonic .22 caliber round and a magnum 12 gauge round. The actual vehicle will determine a lot of accoustic characteristics, as will the positions of firearms and shooters. There are no absolutes in such situations.

But the OP can use these things to vary the situation, results and suspicions.

Jeff

I've actually fired a handgun inside of a car. In the car, even with 32 Db muffs on, my ears were ringing hours later. No question there would have been permanent damage without. Every one of the 20 or so guys who ran that course of fire (and did the same thing) had exactly the same experience.

You do make one good point--I'm assuming that the shot was fired from a pistol minimally adequate as a defensive round. So, .380 at minimum, more likely 9mm, .40, or .45. A .22 short could kill someone in theory with a headshot at close range, but that's not a caliber one would generally choose to take to a fight.

Conrad Adamson · May 23, 2018

Something else to consider is that investigators would look for powder burns or stippling. Either of these would indicate a close range bullet wound.

WeaselFire · May 27, 2018

JNG01 said:
A .22 short could kill someone in theory with a headshot at close range, but that's not a caliber one would generally choose to take to a fight.

Bobby Kennedy was assassinated with a .22.

Jeff

JNG01 · Jun 2, 2018

WeaselFire said:
Bobby Kennedy was assassinated with a .22.

Jeff

RFK's assassination is a great example of the ineffectiveness of the .22 as a fighting cartridge. RFK was shot 3 times at extreme close range with a .22, twice in the chest and once in the head. With a 9mm, or .40, or .45, death from similarly-placed shots would have very likely come within minutes, if not seconds. With the .22 round, though, RFK lived for TWENTY-SIX HOURS before succumbing to his wounds.

WeaselFire · Jun 3, 2018

JNG01 said:
RFK's assassination is a great example of the ineffectiveness of the .22 as a fighting cartridge.

An argument not germane to the OP question and one I won't bother with.

Jeff

jclarkdawe · Jun 3, 2018

A .22 doesn't have the most stopping power and needs careful aiming. But used correctly, a .22 can be a very effective weapon.

And to give a specific example of when a .22 works well, cars would be high on the list. A technique used frequently in the Boston area years ago with organized crime was a driver, victim in the front passenger seat, and a shooter in the back seat. While driving, so the victim didn't suspect anything, the shooter would fire. Weapon of choice was a .22, which has several advantages in this situation. Shot at the base of the skull and the person would be effectively dead, bullet would stay within the skull and not go through the windshield (would not be very comfortable for the driver to have the windshield blow out, as well as being a bit noticeable to police officers), noise would be minimal (again, good for the driver's nerves), and a .22 is easy to conceal.

Caliber of weapon should always be chosen with all the parameters considered.

Jim Clark-Dawe

Al X. · Jun 5, 2018

jclarkdawe said:
A .22 doesn't have the most stopping power and needs careful aiming. But used correctly, a .22 can be a very effective weapon.

And to give a specific example of when a .22 works well, cars would be high on the list. A technique used frequently in the Boston area years ago with organized crime was a driver, victim in the front passenger seat, and a shooter in the back seat. While driving, so the victim didn't suspect anything, the shooter would fire. Weapon of choice was a .22, which has several advantages in this situation. Shot at the base of the skull and the person would be effectively dead, bullet would stay within the skull and not go through the windshield (would not be very comfortable for the driver to have the windshield blow out, as well as being a bit noticeable to police officers), noise would be minimal (again, good for the driver's nerves), and a .22 is easy to conceal.

Caliber of weapon should always be chosen with all the parameters considered.

Jim Clark-Dawe

At the risk of quoting the Anarchist's Cookbook, a .22 deformed and smeared with dog feces can be a very lethal weapon with the intent of creating toxic shock syndrome. But.. it takes time. Unless you got a perfect shot through the eye into the brain, your .22 isn't going to be immediately incapacitating, and that is a factor if the whole thing is to be pulled off. If the vic gets to a hospital, well, they probably can pull through.

If I were a pro hit man (disclaimer, I'm not) I would probably choose a Molotov cocktail or a '57 Chevy as an assassination weapon before a .22.

Well in your instance, the vic has been captured and held down and shot in the base of the skull. Not sure if that works for the subject situation.

Crime (murder) scene investigation - gun shot residue

Jenbob

jclarkdawe

Feeling lucky, Query?

JNG01

CWatts

down the rabbit hole of research...

ironmikezero

practical experience, FTW

WeaselFire

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Hunt & Peck

JNG01

WeaselFire

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JNG01

Conrad Adamson

WeaselFire

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JNG01

WeaselFire

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jclarkdawe

Feeling lucky, Query?

Al X.