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How an ex-FBI profiler helped put an innocent man behind bars

latimes.com

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Re: How an ex-FBI profiler helped put an innocent man behind bars

#21
I remember this case from when it happened. I can't believe it's been that long. It seemed pretty obvious at the time that the parking lot guard was innocent. The DA was stuck on the idea that if he was doing his job he would have made her leave. And if he didn't make her leave, he must have murdered her. It just didn't pass the sniff test.

Re: How an ex-FBI profiler helped put an innocent man behind bars

#22
post #18
post #6

Earlier quoted context omitted.

Can you elaborate? Do you mean the science of DNA testing as a whole is complete nonsense, or just DNA testing as it relates to criminal prosecution?

Not sure why I'm being downvoted, does noone remember this? https://www.washingtonpost.com/local/crime/fbi-overstated-fo... Of 28 examiners with the FBI Laboratory’s microscopic hair comparison unit, 26 overstated forensic matches in ways that favored prosecutors ... The cases include those of 32 defendants sentenced to death. Of those, 14 have been executed

Hair testing is not considered proper DNA testing, as far as I understand. In fact the article you linked to mentions that wrongfully convicted persons were often exonerated via subsequent DNA tests.

Re: How an ex-FBI profiler helped put an innocent man behind bars

#23
post #2

Profiling, like much of "criminal science" such as Arson Investigation is a large part unsubstantiated bullshit. It's amazing how poorly regulated all of it is and how many innocent people are in prison, or executed, because of it.

This is a great article about an arson investigation that turned out to be bogus, leading to someone's execution.

http://www.newyorker.com/magazine/2009/09/07/trial-by-fire

Re: How an ex-FBI profiler helped put an innocent man behind bars

#24
post #4

Earlier quoted context omitted.

DNA testing too, complete nonsense

Unfair sarcasm. DNA is one of the very few forensic tools with any hard science behind it. Even fingerprints can lead to highly conflicting "expert" opinions.

You can get "DNA" at every barbershop. Every overtrusted tool will become a weakspot.

Re: How an ex-FBI profiler helped put an innocent man behind bars

#25
post #7
post #5

The big crime is how little epistemological support there is for some of the big forensic tools (fingerprints, DNA, bite marks, arson spread, etc), how little interest there is in researching these areas, and how trusted they are. But I am curious: apart from TV shows, how important is this kind of evidence in most trials? Is it actually uncommon?

From what I understand DNA has gotten pretty good when used responsibly, but the rest are no better than reading a chicken's entrails. Have I perhaps been misinformed about DNA?

The problem with DNA is that the theoretical random match probability gets thrown at the jury (like one in whatever billion), while in reality the error rate is dominated by lab error (like one in a hundred). But judges tend to exclude evidence of lab error rates (I guess to avoid people thinking the other way, that DNA isn't reliable).

Re: How an ex-FBI profiler helped put an innocent man behind bars

#26

Earlier quoted context omitted.

Unfair sarcasm. DNA is one of the very few forensic tools with any hard science behind it. Even fingerprints can lead to highly conflicting "expert" opinions.

You can get "DNA" at every barbershop. Every overtrusted tool will become a weakspot.

And you leave fingerprints on everything you touch. But, it's all we've got as far as hard evidence aside from testimony and camera recording.

Re: How an ex-FBI profiler helped put an innocent man behind bars

#27
post #25
post #7

Earlier quoted context omitted.

From what I understand DNA has gotten pretty good when used responsibly, but the rest are no better than reading a chicken's entrails. Have I perhaps been misinformed about DNA?

The problem with DNA is that the theoretical random match probability gets thrown at the jury (like one in whatever billion), while in reality the error rate is dominated by lab error (like one in a hundred). But judges tend to exclude evidence of lab error rates (I guess to avoid people thinking the other way, that DNA isn't reliable).

There is also the problem of multiple comparisons when they check DNA against a database the probability of randomly finding a match goes up.

Re: How an ex-FBI profiler helped put an innocent man behind bars

#28
post #7
post #5

The big crime is how little epistemological support there is for some of the big forensic tools (fingerprints, DNA, bite marks, arson spread, etc), how little interest there is in researching these areas, and how trusted they are. But I am curious: apart from TV shows, how important is this kind of evidence in most trials? Is it actually uncommon?

From what I understand DNA has gotten pretty good when used responsibly, but the rest are no better than reading a chicken's entrails. Have I perhaps been misinformed about DNA?

The problems with DNA are contamination and prosecutorial overstatement of probabilities.

Re: How an ex-FBI profiler helped put an innocent man behind bars

#29
post #3

Worth noting that the submitter of this story, user ClintEhrlich, played a main role in freeing the wrongly-convicted man. He posted about it on HN a couple years back, in a highly upvoted and discussed thread (500+ upvotes, 200+ comments): https://news.ycombinator.com/item?id=12010760 Edit: it's an ironic coincidence that this follow-up feature was published on the same day of the news of O.J. Simpson's parole: http…

It's shocking how much "evidence-ish" stuff is permitted, and how evidence is processed by labs integrated with law enforcement and prosecuting bodies. In an era of big data, it's easy to see how "profiling" will turn out to be about as good as a divining rod.
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