ABSTRACT
Physical evidence is defined as any and all materials or items that may be identified as being associated with a crime scene, which, by scientific evaluation, ultimately establishes the elements of the crime and provides a link among the crime scene, the victim, and the assailant. The proper recognition, documentation, collection, preservation, and examination of physical evidence are crucial to the successful reconstruction of a crime scene and litigation in a criminal proceeding. Physical evidence may be present at the crime scene whether it be indoors or outside, on a vehicle, on the victim, on the assailant, and/or his environment. The Locard Exchange Principle is foundational for the explanation of the transfer of evidence — that is, it is not possible to enter a location without changing it in some manner, by either leaving something behind or taking something away. Frequently, blood and trace evidence are transferred between the victim and the accused, victim and scene, and the accused and the scene.
