Expertise:

  1. What sets an expert apart from a novice?
  2. How does forensic expertise develop over time?
  3. Does the speed of expert decision making influence performance?
  4. How does memory for forensic information relate to matching accuracy?



‘CSI’ style TV shows give the impression that fingerprint identification is fully automated. In reality, when a fingerprint is found at a crime scene, it is a human examiner who is faced with the task of identifying the person who left it. Even though fingerprints have been used in criminal courts for more than 100 years, research into forensic reasoning is virtually non-existent.

Most forensic research and expert testimony is based on the uniqueness of marks or features. For example, “no two people share the same fingerprint”. But errors are not due to people having identical fingerprints, errors are due to people who incorrectly match non-matching prints. The same principle holds across all areas of forensics from matching faces in CCTV footage to DNA to bite marks or ballistics. There can be no identification without a human examiner.

One goal of The Forensic Reasoning Project is to shift the focus from the uniqueness of information to studying how human examiners develop expertise with this information. The field of clinical reasoning in medicine, for example, has evolved over the last 40 years after an increasing awareness that physicians’ decisions too often resulted in adverse consequences for patients. Much has been learned about novice and expert differences, the influence of cognitive and perceptual biases, and how to best incorporate such knowledge into practice. Similar research into forensic reasoning will help to ensure the integrity of forensics as an investigative tool available to police, so the rule of law is justly applied.