She studies veins, skin creases on hands to help nab sex offenders

Fortune tellers say they can see the future written in a person's palm, but Professor Sue Black studies the back of the hand to look into a person's past.

- Shabana Begum

Like fingerprints, vein patterns are unique to each person, and the forensic scientist has been mapping suspects' hands to help nab child predators for 17 years.

Prof Black first explored this novel idea in 2004, when the British police came to her for help on a sexual abuse case.

They sent her footage of a young girl being abused. Only the perpetrator's hand and forearm were caught on camera. The girl, who took the video for evidence, had alleged that it was her father abusing her.

"The police came to us and said how identifiable is a hand or a forearm? We said we have no idea... but what I know is that veins are very variable. And when you look at the back of your right hand and compare it to your left hand, it's different," said Prof Black.

Fortunately, the veins on the arm became more marked and visible on the video, thanks to near-infrared light from the camera.

When Prof Black compared the hand in the video with a picture of the father's hand, it was a match.

But there was an element of doubt then because there were no statistics showing how distinct or unique the vein pattern is.