Transfer of Evidence was introduced by Edmond Locard, a criminologist at the University of Lyons in France. According to Locard's exchange principle, a criminal will always leave minute particles of evidence behind on a crime scene because wherever we go, we take something away and leave something behind. Based on this principle and advance in forensics science and modern forensic technology, crimes that were once impossible to prove can now be ascertained with remarkable conviction.
Types of Evidence
According to forensic science professionals, the premise of the transfer of evidence is that it is impossible to interact with our environment without a transfer of evidence occurring. Evidence can include saliva, blood, hair, paint, explosives, semen, skin, fingerprints and other impressions and chemicals. Types of blood splatter or patterns of droplets and sequence of layers are other telling forms of evidence.
Hit and Run Evidence
A forensics scientist investigating an automobile accident will look for glass or paint particles that have been transferred from one vehicle to the other during impact. Glass particles may also be embedded in window wells or other crevices. For hit and run accidents, forensic scientists may find skin, fibers or blood from the victim on the vehicle and paint or glass on the victim.
Hair Transfer and Analysis
Hair fibers that are transferred during a crime can be solid evidence to identify a suspect. Trichology is the study of hair, which forensics scientists employ in hair analysis. The root of the hair that provides DNA is of primary importance in forensics. If hair comes directly from a specific body part, it is a primary transfer. Hairs that are shed and land on furniture, clothing or even pet hair are considered secondary transfer. Hair analysis becomes very complex when forensics scientists begin to catalog hairs by body part, type (human or animal) shaft or root, however, a good hair analysis has solved many crimes.
Vernon J. Geberth , the writer of "Practical Homicide Investigation," identifies two types of transfer evidence that are found sex-related homicide investigations: Trace evidence, in a sex related homicide, can be hair, semen, blood, glass or soil. Transfer evidence can be bloody prints, like shoes, socks or footprints, greasy fingerprints or impressions from fabric. Gerbreth also explains the linkage concept based on the theory of transfer and exchange, distinguishing between direct and indirect transfer: Direct transfer occurs in a sex-related homicide when evidence is transferred to a person or object. Indirect transfer may occur, for example, when rug fibers on the victim are later found in the vehicle of a suspect.
- Photo Credit Creatas/Creatas/Getty Images
Types of Physical Forensic Evidence
No two people have the same fingerprint. That is why fingerprints are the most important evidence to be collected. Fingerprint evidence can...
After Effects of Chemotherapy
Chemotherapy is treatment of disease, usually cancer, using chemicals--delivered orally or intravenously--that kill cells. All drugs have associated side and after ...