Locard’s Exchange Principle

Dr. Edmond Locard

Dr. Edmond Locard

Locard’s exchange principle is a concept that was developed by Dr. Edmond Locard (1877-1966).  Locard speculated that every time you make contact with another person, place, or thing, it results in an exchange of physical materials. He believed that no matter where a criminal goes or what a criminal does, by coming into contact with things, a criminal can leave all sorts of evidence, including DNA, fingerprints, footprints, hair, skin cells, blood, bodily fluids, pieces of clothing, fibers and more. At the same time, they will also take something away from the scene with them. Continue reading