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Letter: Finger of innocence

Published 29 September 2001

From Lawrie O'Connor

I normally have a fair amount of time for Tam Dalyell, but he took a very
firm grasp of the wrong end of the stick on fingerprinting
(Westminster Diary, 1 September, p 53).
Yes, fingerprints are “reliable” as he said—80 per cent
of the time. He acknowledges that this is a 20 per cent failure rate, but then
looks only at one side of the problem.

Fingerprints cannot be used to prove that someone is innocent. A fingerprint,
if it’s a good one, may prove that I, you or Tam Dalyell was at the scene of a
crime. Fingerprints can’t prove when we were there, and they certainly can’t
prove that we were not there, or that we were somewhere else. A smudged print,
on the other hand, if it’s among the 20 per cent of wrongly identified prints,
could be used to convict an innocent party.

Ossett, West Yorkshire

Issue no. 2310 published 29 September 2001

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