So you don't leave fingerprints dummy. In the past, these thieves would probably have never been caught. When there are no witnesses and fingerprints, the police would have had a lot of trouble catching them. She has left a few stray strands of hair behind - and these days, that evidence can be enough to catch the crooks. Scientists like Katie Goss at the forensic science centre can use that hair to track down the baddies.
Police often use fingerprints to catch criminals.
Everyone has fingerprints, and no two persons fingerprints are the same. Everyone also has DNA, and except for twins, everyone's DNA is different. It's in your skin, your saliva, and even your hair. Once they've found it, they can make up a DNA profile. Police can then compare this DNA profile, with the profile from a suspect.