Rethinking the Ken Through the Lens of Psychological Science

Abstract

Canadian courts regularly exclude psychological expert evidence that would explain the factors that produce mistaken eyewitness identifications and false confessions (two significant sources of wrongful convictions). Courts justify these exclusions on the basis that the evidence is not beyond the ken of the trier of fact—the psychologist would simply be describing an experience shared by the judge and jury. In this article, the authors suggest this reasoning rests on two fundamental misunderstandings of psychology: unconscious neglect and dispositionism. In other words, judges mistakenly assume the trier of fact understands the unconscious situational forces that distort memories and cause innocent people to confess. Moreover, judges appear to prefer dispositional evidence of some disorder or syndrome suffered by the accused or by the witness to the crime. After demonstrating evidence of such reasoning in several decisions, the authors suggest reforms based on a more nuanced understanding of human psychology.