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Comment by RajT88 | Hacker News Reader

When I was a kid, I recall police coming to our classrooms to fingerprint us. The whole school got fingerprinted. The idea was to help police if kids went missing.

Whether or not you believe that justification ("Stranger Danger" was a scare at the time), I can promise you those fingerprints were used to put people in jail later.

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> those fingerprints were used

A detective in a ~150K pop. municipality told me that while they might dust for prints, they rarely use them in court because computer matches are very noisy and actually entering prints as evidence in court requires an expensive expert witness to evaluate and attest to a supposed match. The prosecutor can't afford the fees for every case, so a lot of fingerprint evidence goes unused.

Fingerprints are basically circumstantial evidence (unless it's a high profile case that spares no expense). And even though it's difficult to use them in court, it's perfectly fine to use it for probable cause on a warrant. You still need a latent print expert to attest to a judge that they match but it's much less involved than trying to use them in court.

I think that's a bit safer, because you could deduce very private information from a DNA sample, but you can't really tell anything about a person from their fingerprints, except maybe the size of their fingers. It's a one way match

Identical prints do exist. As with lab contamination of DNA, there is a potential for false accusation when you submit to dragnet biometric databases.

> Identical prints do exist.

Evidence?

It's theoretically possible, but as far as I'm aware, no one has found a matching set.

Not whole sets but individual fingers have turned up duplicates.

Source?

( > Evidence? )

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