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Fingerprinting and False Positives

New Scientist News – How far should fingerprints be trusted? (via jwz):

Evidence from qualified fingerprint examiners suggests a higher error rate. These are the results of proficiency tests cited by Cole in the Journal of Criminal Law & Criminology (vol 93, p 985). From these he estimates that false matches occurred at a rate of 0.8 per cent on average, and in one year were as high as 4.4 per cent. Even if the lower figure is correct, this would equate to 1900 mistaken fingerprint matches in the US in 2002 alone.

This is why I’m so unhappy about getting fingerprinted as part of US immigration’s US-VISIT program and similar. My fingerprints have been collected on several occasions as part of that program, and as a result will now be shared throughout the US government, and internationally, and will be retained for 75 to 100 years, whether I like it or not.

As a result, with sufficient bad luck, I may become one of those false positives. Fingers crossed all those government and international partner agencies are competent enough to avoid that!

Update: oh wow, this snippet from the New Scientist editorial clearly demonstrates one case where it all went horribly wrong:

Last year, an Oregon lawyer named Brandon Mayfield was held in connection with the Madrid bombings after his fingerprint was supposedly found on a bag in the Spanish capital. Only after several weeks did the Spanish police attribute the print to Ouhnane Daoud, an Algerian living in Spain.

eek! Coverage from the National Assoc of Criminal Defense Lawyers, and the Washington Post.

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