Juror perceptions of opposing expert forensic psychologists

Pre-existing beliefs frame people’s perception and interpretation of new, relevant information. For instance, juror’s attitudes about mental illness will affect how they evaluate testimony from forensic psychologists and, ultimately, their judgment about the case. Furthermore, because each legal party secures experts that will favor their side, jurors often hear contradictory expert opinions. The current work focused on how participants’ initial opinions about mentally ill individuals might interact with the order in which opposing expert testimony is presented. Participants evaluated facts from insanity defense trials and two examples of expert evidence, updating their decisions and ratings after receiving each new piece of information. Inspired by belief perseverance and cognitive bias research, we examined participants judgments in light of how their initial impression of a case compared to that of the first expert. Participants’ initial views, and whether the first expert presented a congruent view, mattered—incongruent experts inspired many people to change their minds, especially among those willing to endorse the plea initially. Many reverted to their original opinion, though, after the subsequent congruent testimony. We discuss the role of belief perseverance and confirmation bias in these findings and future directions for investigating the influence of juror’s pre-existing beliefs

Confirmation bias · Criminology · Forensic psychology · Forensic science · Perception · Deception detection and forensic psychology · Medicine · Psychology · Social Psychology