NACDL

A particularly critical and challenging aspect of criminal defense litigation is the interpretation of forensic evidence. This article is designed to address a question from the perspective of the criminal defense attorney: Did law enforcement follow standardized evidence processing and collection guidelines?

It is vital that proper forensic information obtained by law enforcement be incorporated into the overall evidentiary tableau. Forensic evidence evaluation by the defense attorney poses a challenge for several reasons. First, law enforcement officers collect and integrate the forensic evidence without the defense attorney’s input or control. Second, the crime scene is subject to degradation almost immediately after the occurrence of the event. A fundamental principle of entropy is that any system tends to disassemble into its component parts without the constant application of external influences. With respect to a crime scene, there are constant environmental changes (e.g., temper