Posted on 05/02/2016 2:25:05 PM PDT by Chasaway
I need some general firearms/ballistics information.
I'm working on a criminal defense case. The defendant is accused by the state of shooting his girlfriend in the back of the head with an AR-15 at 10 feet...using a .223 round.
The defendant is a real scumbag and knows he's going to the pen over this. BUT, he claims he accidentally discharged the gun, it caromed off of a linoleum-covered concrete floor and then struck her. It all occurred in a very small kitchen.
My working hypothesis is that this WAS an accidental shooting and that the bullet DID ricochet off of the floor. That means that the defendant couldn't have MEANT to shoot her, because there is no way to accurately predict, ad hoc, the performance of a bullet after caroming off of a concrete floor.
Also, if he HAD shot her directly from 10 feet, I wouldn't expect the round to fragment and stay in her brain pan and I would expect to see some other residue from the round on her clothes or in her hair, etc.
Background stuff is:
1. There WAS a hole in the linoleum. Crime scene photographers took several pictures of it. There were no other holes and this one appears to be of recent causation. However, the police did not mention in their report;
2. LEO initially arrested him for a negligent/manslaughter, but the DA ultimately raised it; 3. ME said the bullet was "fragmented" and never left her skull;
4. No gunpowder residue tests were conducted on the victim or the floor; only on the shooter's hands.
5. I am waiting to hear from the attorney as to the round's manufacturer, the weight of the bullet and whether the round was FMJ, SP or HP. I am operating under the assumption it was FMJ at this point. I also don't know the length of the barrel.
What I'd like to ask are some general questions, then I'd like to see if I can find some relatively unimpeachable sources to back the answers up. So, opinions or general statements would be helpful. ALSO, any sources for hard data (manuf. sites, FBI studies, etc.) that I could use to back up anything I attempt to present.
1. What is the muzzle velocity of the round?
2. What is the velocity of the round at 10 feet?
3. What penetration testing has been done on the round at 10 feet?
4. What gunpowder residue patterns should be able to be discerned on the victim, assuming a 10 foot range?
5. Is there a reasonable likelihood that a FMJ .223 at 10 feet would remain in the skull?
6. Is there a reasonable likelihood that a FMJ .223 at 10 feet would break up into fragments, assuming it entered at the lower rear part of the skull?
7. What evidence (metal remnants, gunpowder residue, etc.) should have been obtainable from the linoleum floor if the rifle was pointed at the floor 5 feet or so in front of the shooter?
It is recognized that a LOT of this can't be known until the round used is identified. But general, or close estimates, would help at this point.
I appreciate the help. Leaving aside the character of the defendant, it's an interesting case. The attorney was absolutely floored when I brought these issues up, never having even considered them.
If you have any other thoughts, I'd like to hear those, too. Even if they're troubling for the defense. FReepmail me if you like.
C
If you’re working for the defense, do you really want to put your theories on the internet where the prosecutors can read them?
You cannot fudge entry angle and blood splatter.
Test Protocol
Tests 1-6:
Bare gelatin, heavy clothing, automobile sheet metal, wallboard, plywood, and vehicle windshield safety glass, were shot a distance of 10 feet from the muzzle. The vehicle safety glass was set at an angle of 45 degrees to the horizontal, with the line of bore of the rifle/SMG offset 15 degrees to the side resulting in a compound angle of impact for the bullet upon the glass, which simulates a shot directed at the driver of a car closely missing the shooter. Furthermore, the gelatin was covered with light clothing and set back 18 inches behind the glass. All gelatin blocks, with the exception of the body armor barrier, were set 18 inches behind each solid obstacle shot.
http://www.olyarms.com/index.php?option=com_content&task=view&id=14
Any idea what the angle of incidence would be?
Sadly, almost NONE of it can be known until the round is fully identified.
Forensics should have known all of that by the time his charge was upped. And if you don't have all such details by the time Discovery is over, either they are incompetent or are covering things up. (IMHO)
If you could share a crime scene photo of the hole in the linoleum, we might be able to make a good guess as to whether it was caused by a bullet.
Ask your client for money to hire an expert witness. If he doesnt have it or is indigent, ask the Court for money to hire an expert witness. If you dont ask, you dont get. What do you have to lose by asking? Answers here will get you nowhere fast.
If you're looking for testimony, you're going to have to get an accredited ballistics expert.
Okay. Is there ANY muzzle velocity out of ANY barrel length AR that would break up in someone’s skull at 10 feet?
And what would that be?
Because if he doesn’t have it, it didn’t do it.
You’re kind of making my point. ANY angle of incidence would leave my guy out of a murder charge.
It was 10 feet from muzzle to the back of her head.
Whatever the angle is, it would probably have to be steep, yes?
Thanks! That’s helpful.
“5. Is there a reasonable likelihood that a FMJ .223 at 10 feet would remain in the skull?”
I have shot many things with a 223/5.56mm. I would be stuned to hear that an FMJ stayed in a human skull when hit from 10 feet. Not impossible but way out on the odds. Also, I would be skeptical about the bullet being a real FMJ if fragmented.
Yes. That’s the problem.
I don’t think there’s any reasonable way to dispute the physics of this.
It isn’t so much the velocity that is critical, it is the projectile construction. There are .223 /5.56 rounds that won’t fragment when they hit armor. There are others that will about turn into dust if they hit an apple.
Yep. That’s what I’m thinking.
I think the only way it could fragment would be if it HAD caromed off of a concrete floor and seriously compromised its integrity.
Thanks.
Dude. Stop.
This is a criminal case and you are posting in a public forum.
If you won’t stop, please freepmail me your name and State of practice so I can avoid you like the plague.
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