The History of Forensics


Forensics investigation relies on one basic principal - that every contact leaves a trace.

Crime scene investigation

This was a discovery made by Edmund Locard - the head of the world’s first crime investigation laboratory based in Lyon, France.

Locard’s principal of exchange, states that if there is contact between two objects there will be an exchange so the criminal will leave something at the scene of the crime, fingerprints, hair, fibres, saliva etc and they will take something away from the crime scene.



The principal has remained unchanged for 100 years.

Crime scene investigation

Locard’s influence in the forensic world remains as strong today as it did in 1910 when the lab was first opened. Many forensic companies incorporate Locard’s name within their organisation in acknowledgement of the contribution he made.

Police officers are trained to apply this principal at every stage during the investigation of crime.

Their are various types of forensic evidence, including:

  • Fingerprints 

  • DNA

  • Footprints

  • Fluids & Residues

  • Paint

  • Glass

  • Fibres

Forensic evidence can be gathered from:

  • Blood

  • Cigarette butts

  • Discarded wallets / handbags

  • Blobs of spittle

  • Chewing gum

  • Victim swabs - bitten, kissed, struggled

  • Fingernails / Toenails

  • Combs, Razors, Toothbrush

  • Cigarette lighters

  • Used clothing, underwear, watch straps and many more