When "scientific" evidence isn't ...

For years, the FBI used a forensic technique called comparative bullet lead analysis. When lead bullets are made, they absorb trace elements like copper, bismuth and silver. Theoretically, bullets from the same box would have similar levels of those elements.

So ... investigators decided they could match a bullet found at a crime scene with one possessed by a suspect, based on whether they had the same amounts of trace elements. The FBI used this in hundreds of cases.

Until a few years ago, when the National Academy of Science explained that, yes, the stuff about the trace elements was true. But there's nothing to stop another bullet in a different box from a different factory to have similar levels of trace elements. The "scientific proof" wasn't very scientific. Since then, the FBI has been reviewing all of those cases. Three people, once convicted of murder, have been freed as a result.

Comments

[Stifled Freedom]

Well the presumption is that every box of bullets is a different manufacturing batch. That is not the case. One batch might be use to produces hundreds of boxes of bullets....which doesn't necessarily narrow it down.

[cripjak]

If the bullet doesn't fit you must acquit.

[Patty PV]

Wow, they just now got around to figuring this out?

[Greg]

Lucky they didn't get that DP treatment.

[Tom K]

It's a little hard to believe that even they didn't figure this out a long time ago. An awful lot of bullets can come out of a hundred pounds of alloy.

The controversy about DNA testing gets me, too, because if nine of thirteen markers is enough for a conviction, then convictions can be had when four of the thirteen DNA markers don't match, which should prove that the DNA doesn't come from the same person.

[Boogaloo Shrimp]

Why doesn't the NRA spend money to fund studies on subjects like this? I'll bet that they haven't done a thing, while groups like the ACLU have probably done a ton of work.