Your fingerprint at the scene of a crime doesn't prove anything

We've all seen police dramas where triumphant suspects are appalled to learn that their fingerprint is on, say, the underside of the door handle of the victim's car. But what qualifies as a 'matching' print? And is the system always perfect, or does it make mistakes? Take a look at how incriminating your fingertips… » 4/09/12 3:08pm 4/09/12 3:08pm