Crime Scene Investigation Module 1 The History of

Crime Scene Investigation Module 1 – The History of Crime Scene Investigations

Dr. Edmond Locard • 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. • 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.

Contributions • Locard is also renowned for his contribution to the improvement of dactylography, an area of study which deals with fingerprints. • 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. • 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”. • Edmond Locard died in 1966.

Forensic Microscopy • Since the time of Locard, forensic microscopists all over the world have understood that “The microscopic debris that covers our clothing and bodies are the mute witnesses, sure and faithful, of all our movements and all our encounters. ” • Forensic microscopy is always of interest; everyone likes a good mystery; and recent high profile cases, news accounts of notable cases, and television fiction have repeatedly brought forensic microscopy into the limelight.

Real Evidence • Microscopy leads to images that lead to real evidence. Real evidence consists of things brought into the courtroom versus the assertions of witnesses about things, and conveys a relevant firsthand sense impression to the trier of fact versus those which serve merely to report the secondhand sense impressions of others. • Real evidence presents logistical difficulties for the courts. Since the courts are basically structured, architecturally and otherwise, to receive the testimony of witnesses, the presentation of real evidence may require that the court physically move to receive unwieldy objects like microscopes into the courtroom, actions which may occasionally delay and confuse the proceedings.

Fingerprint Microscopy • Fractured patterns include the friction ridge patterns in fingerprints, surface striations due to tool marks, impressions of worn and chipped shoe soles , broken objects, blood spatters, and fabric impressions. • The forgery of fingerprints was also investigated by Locard. In 1907 he discovered a procedure for making counterfeit fingerprints by the use of a mold (like a rubber stamp) made from gutta-percha. • There are two relatively easy ways to forge fingerprints. • One is to make a stamped print which is a replication of a fingerprint by a rubber stamp, cast, molding, plate, or die, i. e. , a reproduction. • The other is to collect an original latent fingerprint from an innocent surface and claim it was collected from another incriminating surface, i. e. , a transferred powdered lift.

Firearms Microscopy • The firearm from which a bullet or cartridge case has been fired is identified by the microscopical comparison of the unique striae (toolmarks) left on the bullet or cartridge case from the worn, machined metal of the barrel, breach block, extractor, or firing pin in the gun.

The Comparison Microscope • It was Gravelle who mistrusted his memory. “As long as he could inspect only one bullet at a time with his microscope, and had to keep the picture of it in his memory until he placed the comparison bullet under the microscope, scientific precision could not be attained. He invented the comparison microscope and Goddard made it work. ” • The analysis of gunshot residues (GSR) using scanning electron microscopy (SEM) has proven to be a valuable addition to the trace evidence arsenal. • Particles containing lead, antimony and barium are considered unique to gunshot residues and are real microscopic evidence associated with the firing of a gun.

Fragment Fracture Matching • Fragments are broken or torn objects, split apart by force into separate pieces. • If one piece is found at the crime scene and another matching piece in the perpetrator’s pocket, an association is established. • Positive identifications are accomplished with magnified observation of the fractured surfaces and refitting, and made real evidence by photomicrography.

Summary As you can see, the history of crime scene investigations started in the 1800’s with Edmond Locard and has rapidly developed to what it is today. While microscopy still brings many logistic issues with it into the courtroom, it provides absolute, real evidence and can be the true difference in proving guilt or innocence in a court of law.