Court Case Context and Fluency-Promoting Photos Inflate the Credibility of Forensic Science
Abstract
Abstract. Faulty forensic science sometimes makes its way into the courtroom where jurors must evaluate its credibility. But at least two factors may inflate how credible jurors find claims about forensic science: the mere context of a court case and the cognitive fluency of the evidence. To investigate, we asked people to judge various claims about forensic science as true or false. In Experiment 1 (N = 287), we manipulated court case context by either attributing the claims to an expert in court or not specifying their origin. In Experiment 2 (N = 320), we manipulated courtroom setting orthogonal to source expertise. In both, we manipulated fluency via the presence of related but nonprobative photos. We found each factor increased people’s bias to judge forensic science claims true. Our findings suggest the justice system must improve the quality of forensic science upstream from the courtroom to ensure jurors’ credulity is warranted.
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