Born in 1877, Dr Edmond Locard was a French criminalist renowned for being a pioneer in forensic science and criminology, often informally referred to as the "Sherlock Holmes of France". Whilst studying medicine he developed an interest in the application of science to legal matters, writing his thesis on Legal Mecicine under the Great King (La medecine legale sous le Grand Roy). He went on to publish over 40 pieces of work, the most famous being his seven-volume series Traite de criminastique (Treaty of Criminalistics).
For a while Locard worked as the assistant of Dr Alexandre Lacassagne and, a few years later, began pursuing his career in law. He passed the bar in 1907 and went on to study alongside anthropologist Alphonse Bertillon, famous for his anthropometric system of identifying criminals. During the First World War, Locard worked with the French Secret Service as a medical examiner, attempting to identify cause and location of death by examining the stains and damage of soldiers' and prisoners' uniforms.
In 1910, Lyon police department finally offered Locard the opportunity to form the first police laboratory in the form of a few small attic rooms, where evidence collected from crime scenes could be scientifically examined. It was not until 1912 that the police department officially recognised the laboratory.
Locard is also renowned for his contribution to the improvement of dactylography, an area of study which deals with fingerprints. After the laboratory in Lyon was established, he developed the science of poroscopy, the study of fingerprint pores and the impressions produced by these pores. He went on to write that if 12 specific points were identical between two fingerprints, it would be sufficient for positive identification. This work led to the use of fingerprints in identifying criminals being adopted over Bertillon's earlier technique of anthropometry. In 1929, Locard and numerous other criminalists founded the International Academy of Criminalistics in Switzerland. However this building did not survive the Second World War.
However Edmond Locard is perhaps most well-known for his formulation of Locard's Exchange Principle, a theory relating to the transfer of trace evidence between objects, stating that "every contact leaves a trace". The theory dictates that when two objects come into contact with one another, each will take something from the other object or leave something behind.
Edmond Locard died in 1966, however his exchange principle has become a great influential piece of work in forensic science, and is frequently quoted to this day.
Petherick, W A. Turvey, B E. Ferguson, C E, 2010. Forensic Criminology. London: Elsevier Academic Press.
Modern Microscopy: The Locard Exchange. [online] Available at: [http://www.modernmicroscopy.com/main.asp?article=11]