A lot of forensics techniques are turning out to be unreliable. I wonder how many cases were resolved primarily based on ballistics evidence that should be overturned or at least reviewed?
this post was submitted on 17 Jan 2024
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todayilearned
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i always thought the whole, bullets being like fingerprints thing, didn't make sense.
i could see them narrowing down the type of gun... but not the exact one...
especially since they're regularly disassembled, cleaned and oiled...
They can allegedly match the rifling marks left on bullets to barrels, but if you think about it, the barrels of thousands of guns are probably machined with the same tools, using the same drill press or whatever to make the barrels hollow and cut the rifling into them.
Also matching a caliber could be tricky since there are numerous cartridges that use an approximately 9mm sized bullet (among others). For example a 9x19 standard 9mm cartridge uses a .355" diameter bullet, and a .380 Auto bullet is .355" diameter, and a 38 Super bullet should be .356" diameter, and a 38 Special bullet should be .357" in diameter, and a .357 Magnum is .357" in diameter. But if those cartridges were loaded with solid lead bullets instead of copper encased bullets, they should be sized .001" larger in each case. And then they are being forced down the rifled barrels at extremely high speed and pressure and temperature. Lots of room for mixups
The machine tools used to cut the barrels and other parts have replaceable cutting elements, but your point still stands - nobody is keeping track of how many barrels or which barrels were turned with what cutter on what day.
There's an even more damning argument, however. All a potential murderer has to do is shoot a couple of boxes of rounds through their gun before shooting their victim. Then they clean the gun and would you look at that, the clean barrel makes different marks than the dirty one.
Edit: I remember that I could fire .38 special through my .357, and I often did for target shooting because it was cheaper.
Wki lists over 40 pistol rounds with a ~9mm diameter. I am not going to say all of them are common but still that seems like a pretty big problem with identification.
The trick for the police is to entice you to incriminate yourself. So it doesn’t matter what science is behind it junk or legit, if you admit to doing it, they can file the charges as they have their “proof”. This is why we don’t talk to police, kids.
*edit.
This goes for anything. Got pulled over? do not admit you were going 20 over the speed limit. Stopped for failure to stop a red light, “No sir, i was a complete stop.”.
well, i guess if you shoot someone, i do hope you get tricked into admitting it...
the rest of the criminal "justice" system is bullshit, but i do prefer to separate murderers from other people...
....
regarding never admitting something, sometimes it actually works in your favor... especially, or only really, if you're directly caught.
lying to a cop will piss them off, and is technically another crime. apologizing will often get you you a warning...
(the 5th means you don't have to incriminate yourself, but doesn't give you permission to lie)
especially if you look chagrined and throw a "sir" in there...
source: lifelong petty criminal
p.s. you can kinda combine the two with "oh did i? i'm sorry... i thought i came to a full stop..." and then fight it in court.
Lying to a cop is not a crime.
can be... i.e. “Nobody shall give, either orally or in writing, information to a peace officer performing their duties, when they know the information is false.”
- some california law
Most forensic science is not reliable.
It’s interesting how much of it is junk science.
Golly, who knew. And I had redditors telling me I was full of shit for calling this out.
Watch, I'll call it out on here some day and get the same exact response.
@RaoulDook explains it better than I ever have.
"There was a study called Ames 2, and what that study found that when they tried to reproduce the opinions of one examiner versus another examiner, they found that over 50% of the time, the second examiner came to a different conclusion on the same evidence than the first examiner," Gilleran explained.
Yeah, that's pretty damning.