Sensitizing jurors to eyewitness confidence using "reason-based" judicial instructions

Abstract

We examine a new paradigm for jury instructions regarding eyewitness testimony, in which the judge provides concise reasons why jurors should discount an eyewitness's courtroom confidence and instead focus on the eyewitness's confidence at the time of a police lineup. In Study 1, 1,614 participants ("mock jurors"), representative of the U.S. population, viewed videos of eyewitness testimony and judicial instructions. We found that instructions using the reason-based paradigm reduced guilty votes. Study 2 (N = 2,911) examined whether reason-based instructions sensitized jurors to weak (low initial confidence) versus strong (high initial confidence) eyewitness identifications, and whether the instructions needed to be directive ("You should consider ... "). Jurors who heard the instructive, reason-based instructions better differentiated between more and less reliable eyewitnesses relative to the other instruction conditions. These results suggest that reason-based jury instructions can increase discriminability among laypersons, and that judges should be mindful in phrasing and communicating such instructions.