Sunday, October 07, 2012

False confessions and 'corroboration inflation'

Forensic pscyhologist Dr. Karen Franklin has a thoughtful post on the effects of false confessions on experts' analysis of evidence and on legal actors in the justice system. Yes, she says, false confessions have "produced profound miscarriages of justice," but:
What if, once police elicit a false confession from a suspect, it contaminates everything and everyone in touches -- from the prosecutor, the judge, and even the suspect's own attorney all the way to the fingerprint identification and even, perhaps, the DNA match?

That is the troubling thesis raised by Saul Kassin, a pioneer in the psychological study of false confessions, in an article in the current issue of the American Psychologist.
"Corroboration inflation"

Research shows us that such a contaminating effect is plausible. For example:
  • Fingerprint experts who were told the suspect had confessed were more likely to change their opinion and make an incorrect match, as compared with experts who were told the suspect was already in custody at the time of the crime
  • Polygraph examiners were significantly more likely to opine that an inconclusive chart showed deception when they were told the suspect had confessed.
Such findings may extend to other forensic science that requires subjective judgments, Kassin argues, including comparative analyses of ballistics, hair and fiber, shoeprints, tire tracks, handwriting and even DNA.
See the rest of the post for more and also an abstract of the academic article she based it on.

1 comment:

Anonymous said...

Dr. Franklin is great!
But I must also point out that this is a great example of, as is already known, the fallability of some of our "scientific" forensic tests. If they are open to interpretation, and that interpretation can be swayed by a false confession, then they really aren't reliable at all!