The Role and Impact of Forensic Evidence in the Criminal Justice Process
Joseph Peterson, Ira Sommers, Deborah Baskin, and Donald Johnson
Introduction
Over the past twenty-five years, the forensic sciences have made dramatic scientific breakthroughs (DNA typing, physical evidence databases, and new scientific instrumentation) but studies are needed to assess the contribution of such advancements on the role and impact of scientific evidence in criminal case processing. Targeted studies have evaluated the value of DNA evidence in property crime investigations, but no studies have reviewed the full array of scientific evidence present at crime scenes. In 2006, the National Institute of Justice funded this project to address the following four goals:
Objective 1—Estimate the percentage of crime scenes from which one or more types of forensic evidence is collected;
Objective 2—Describe and catalog the kinds of forensic evidence collected at crime scenes;
Objective 3—Track the use and attrition of forensic evidence in the criminal justice system from crime scenes through laboratory analysis, and then through subsequent criminal justice processes; and
Objective 4—Identify which forms of forensic evidence contribute most frequently (relative to their availability at a crime scene) to successful case outcomes.