• xylol@leminal.space
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    8 hours ago

    Finger print matching doesn’t really work well its all just a guess with no universal criteria on how close a smudge has to be to your fingerprint to be used

    • cynar@lemmy.world
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      3 hours ago

      It can be used more empirically. The more matching points, the less likely a given match is down to random luck. A smudge will have relatively few useful points, and so far less reliability.

      The big problem is you can either use fingerprints to identify someone to a scene, or to search for a match in a database. 1 in a million sounds impressive to a jury, and is in a 1 to 1 test. Compare it to a database of 10 million, and you will expect to get 10 matches by random chance alone.

    • Chozo@fedia.io
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      6 hours ago

      There’s also no evidence to suggest that fingerprints are truly unique at all.

  • Dagwood222@lemm.ee
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    11 hours ago

    True story.

    This is back in the 1960s. A Texas bank is putting up a new building and sets up a temporary office in a trailer. There’s a one ton safe in the trailer. A crook figures that a dozen strong guys would have no problem lifting the safe by hand and carrying it out. He puts together a team and they do the job. Something goes wrong and they end up dropping the safe. One crook’s finger is caught under the safe. He manages to get away, but when the police lift the safe they find his finger tip. And yes, they had his fingerprints on file.