Improving juror assessments of forensic testimony and its effects on decision-making and evidence evaluation.

Abstract

Objective: We explored whether an educational forensic science informational (FSI) video either alone or with specialized jury instructions would assist mock jurors in evaluating forensic expert testimony. Hypotheses: We predicted that the FSI video would help participants distinguish between low-quality and high-quality testimony, evidenced by lower ratings of the testimony and the expert when the testimonial quality was low compared with when it was high. Method: Jury-eligible adults (N = 641; Mage = 38.18 years; 77.4% White; 8.1% Latino/a or Hispanic; 50.1% male) watched a mock trial and were randomly assigned to a no-forensic-evidence control condition or to a test condition (i.e., participants either watched the FSI video before the trial or did not and either received specialized posttrial instructions or did not). In the test conditions, a forensic expert provided low-quality or high-quality testimony about a latent impression, and participants rated the expert, their testimony, and the forensic evidence. All participants rendered verdicts. Results: The presence of the FSI video interacted with testimonial quality on ratings of the expert and forensic testimony: In the video-present condition, participants rated the expert in the low-quality testimony condition lower than did participants in the high-quality testimony condition (between-condition differences for credibility: d = –0.52, 95% confidence interval [CI] [–0.78, –0.27]; trustworthiness: d = –0.67, 95% CI [–0.92, –0.42]; knowledgeability: d = –0.54, 95% CI [–0.80, –0.29]). The pattern was the same for the expert’s testimony (between-condition differences for convincingness: d = –0.41, 95% CI [–0.66, –0.16]; validity: d = –0.60, 95% CI [–0.86, –0.35]; presentation quality: d = –0.51, 95% CI [–0.76, –0.25]). Participants’ ratings in the video-absent condition did not differ on the basis of testimonial quality (ds = –0.07–0.11). The ratings of the print evidence and verdicts were unaffected. Specialized jury instructions had no effect. Conclusion: The FSI video may be a practical in-court intervention to increase jurors’ sensitivity to low-quality forensic testimony without creating skepticism.

“Not Scientific” to Whom? Laypeople Misjudge Manner of Death Determinations as Scientific and Definitive

“…While our study included a cross-examination, it was rather benign and constant across conditions, and so we cannot say whether or how it affected jurors' decision-making. Some studies have tested other ways to make jurors more discerning in their reliance on forensic expert testimony-such as judicial instructions (Eastwood & Caldwell, 2015), visual aids (Ribeiro et al, 2023), or educational videos (LaBat et al, 2023)-and those methods have also yielded mixed results. Future research should continue to examine how laypeople appraise expert testimony from medical examiners specifically, including how cross-examination might influence those appraisals.…”