Microbe fingerprints on clothing could aid crime-solving based on Locard's "principle of exchange."

A 'microbe fingerprint' on clothing could help forensic scientists solve crimes, according to a new study. The concept, based on French criminologist Edmond Locard's "principle of exchange" from the early 1900s, states that every contact leaves a trace. Traditional evidence like pollen, sand, and fibers can be limited, but researchers now believe that microbes on clothing can be used to link suspects to crime scenes.