Understanding and Mitigating Bias in Forensic Evaluation: Lessons from Forensic Science

Abstract

Criticism has emerged in the last decade surrounding cognitive bias in forensic examinations. The National Research Council (NRC, 2009) issued a report that delineated weaknesses within various forensic science domains. The purpose of this article is to examine and consider the various influences that can bias observations and inferences in forensic evaluation and to apply what we know from forensic science to propose possible solutions to these problems. We use Sir Francis Bacon's doctrine of idols—which underpins modern scientific method—to expand Dror's (2015) five-level taxonomy of the various stages at which bias can originate within forensic science to create a seven-level taxonomy. We describe the ways in which biases can arise and impact work in forensic evaluation at these seven levels, highlighting potential solutions and various means of mitigating the impact of these biases, and conclude with a proposal for using scientific principles to improve forensic evaluation.