Dr. Edmond Locard was a pioneer in forensic science who became known as the Sherlock Holmes

Sherlock Holmes

Sherlock Holmes is a fictional detective created by Scottish author and physician Sir Arthur Conan Doyle. The fantastic London-based "consulting detective", Holmes is famous for his astute logical reasoning, his ability to take almost any disguise, and his use of forensic science skills to solve...

 of France

France

The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...

. He formulated the basic principle of forensic science: "Every contact leaves a trace". This became known as Locard's exchange principle

Locard's exchange principle

The Locard exchange principle, also known as Locard's theory, was postulated by 20th century forensic scientist Edmond Locard.Locard was the director of the very first crime laboratory in existence, located in Lyon, France...

.

Locard studied medicine and law at Lyon, eventually becoming the assistant of Alexandre Lacassagne

Alexandre Lacassagne

Alexandre Lacassagne was a French physician and criminologist who was a native of Cahors. He was the founder of the Lacassagne school of criminology, based in Lyon and influent from 1885 to 1914, and main rival to Lombroso's Italian school.- Biography :He studied at the military school in...

, a criminologist and professor. He held this post until 1910, when he began the foundation of his criminal laboratory.