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Ballistic identification problems
From View from the Porch comes an interesting discussion about whether ballistic ID, especially bullet striations, is junk science. The data summed up certainly suggests that.
(One of the first such IDs, maybe the first, happened here in Tucson. In the old law school they had the exhibits on the wall. No use of comparative microscopes, etc., the witness just looked at the bullets with a magnifying glass. One exhibit was labelled "bullets from different guns look different," with a picture of an assortment. Well, yes, they were an assortment of jacketed and lead bullets, damaged and undamaged, ones with wide rifling grooves and ones with narrow).
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Allan Jones had a marvelous story on the subject in the latest issue of Shooting Times.
In a murder trial, the prosecution's expert witness showed microphotographs and solemnly assured the court and jury that both bullets were fired from the same gun. The expert witness for the defense examined the two bullets in evidence and asked the prosecution why did one bullet have three grooves and the other had four. Oops.
And who's word do we have that fingerprints are unique? The FBI's?
They figure since identical twins have different prints they must be unique - some day we may actually know
An independent audit by a reliable third party might help.
But they refuse to make their database available for that
We can't get the federal government as a whole to give correct financial audits- you know, the kind they require from citizens.
This from "truthinaccounting.org"-
"U.S. Government Accountability Office (GAO) has delivered a disclaimer of opinion on the overall financial statements of the federal government of the United States – every year since 1997."
I wonder if modern manufacturing techniques, like computer aided machining and carbide tooling, have erased, or at least minimized, the small differences from gun-to-gun that forensic ballistics used to be able to rely on?
It seems obvious to me that modern expanding bullets are more distorted after firing than the bullets of my youth were, as well. That can't help.
The other one that always sticks in my craw, is that of the lie detector test. You see it all the time on television. " Well, he passed a lie detector test, so we crossed him off the list of suspects, since he passed a lie detector test."
There is a reason that they are not admissible in court. Because they can indeed be beaten. I have read a couple of ways that convicts have been known to beat them. And now the bullet matching test is once again in the news, since someone is investigating the science of whether or not it really can prove that a certain gun was the only gun that could have fired that one bullet on that one occasion. I never believed it myself, but never could come up with a way to prove it. Now, it sounds like someone is trying to find out, with actual scientific testing. I wonder how many convicts will appeal they're cases ased on this.