If you only listen to one radio programme this month, make it this one. The BBC Radio 4 programme Fingerprints on Trial explores how identifying people at crime scenes by their prints is subject to serious psychological biases and is not the exact science that we, and ironically, the forensic fingerprint community, like to believe.
It covers some spectacular high-profile cases, the science behind how prior knowledge can bias the supposedly objective identification of prints, and the baffling fingers-in-the-ears lalalala response of some fingerprint experts who just completely deny it’s a problem.
So here’s how these biases could work in practice. Fingerprint examiners in this country [the UK] generally know the type of crime their working on. Any murder is high profile, so the chances are they’d know quite a bit about the case. They might see crime scene photographs and might even have heard snippets from detectives working on the case. And then when they start to check the fingerprints from the murder scene, evidence from cognitive psychology shows that what they know, or think they know, can influence what they then see in the prints.
Combines gripping sad-but-true whodunits, cutting edge cognitive science and a pressing issues for forensic science.