Until now, fingerprints were only able to allow forensic experts to discover the identity of a person, but a new method of analyzing them is able to extract information about the substances that the person they were taken from has come in contact with.

The team led by R. Graham Cooks, a analytical chemistry professor, came up with a method of discovering chemical substances that reside in fingerprints. If a person is handling, let's say, cocaine, the drug sticks on his or her fingers in very small quantities of a few parts per million, no matter how well that person would be cleaning his hands. This tiny amount of the substance is then transferred to the objects that the person touches and remains there located at the point of the fingerprint's ridges.

This new method will allow the police to separate the fingerprints of the person who committed a crime from the ones of other people that just happened to touch objects at the crime scene.

The same method can be used to separate one person's fingerprints from beneath others, where they appear in layers. To do this, forensic experts would need to have only a small part of the fingerprint separated from the others. By analyzing the distribution of chemical compounds found in this part of the fingerprint, they would be able to filter it from the layer of fingerprints, thus acquiring a clear image of it.

Forensic experts will be able to put Mr. Cooks' research into practice in about two years, when it will be ready for mass usage.