Edmond Locard

Edmond Locard

Dr. Edmond Locard (1877 – 1966) was a pioneer in forensic science who became known as the Sherlock Holmes of France. He formulated the basic principle of forensic science: "Every Contact Leaves a Trace". This became known as Locard's exchange principle.

Locard studied medicine, and law at Lyon, eventually becoming the assistant of Alexandre Lacassagne, a criminologist and professor. He held this post until 1910, when he began the foundation of his criminal laboratory. He produced a monumental, seven-volume work, "Traité de Criminalistique", and in 1918, developed 12 matching points for fingerprint identification. He continued with his research until his death in 1966.

Locard suceeded in persuading the Lyons Police Department to give him two attic rooms and two assistants, to start what became the first police laboratory.

The young Georges Simenon, later to become a well-known detective writer, is known to have attended some Locard lectures in 1919 or 1920.


'Wherever he steps, whatever he touches, whatever he leaves, even unconsciously, will serve as a silent witness against him. Not only his fingerprints or his footprints, but his hair, the fibers from his clothes, the glass he breaks, the tool mark he leaves, the paint he scratches, the blood or semen he deposits or collects. All of these and more, bear mute witness against him. This is evidence that does not forget. It is not confused by the excitement of the moment. It is not absent because human witnesses are. It is factual evidence. Physical evidence cannot be wrong, it cannot perjure itself, it cannot be wholly absent. Only human failure to find it, study and understand it, can diminish its value. '

-Professor Edmond Locard


*The Illustrated guide to Forensics - True Crime Scene Investigations By Dr Zakaria Erzinçlioglu

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