B – 122 The Influence of PTSD Diagnosis Timing on Mock Juror Guilt Ratings in a Military Veteran Murder Trial

Abstract Objective Our experimental research examined how PTSD diagnosis timing affects mock jurors’ judgments in a military veteran murder trial. Method The sample of 597 jury-eligible U.S. adults (M age = 40.08, SD = 12.94) included men (49.7%), women (48.6%), and other genders (1.7%). Participants were White (77.8%), African American/Black (9.5%), Asian/Pacific Islander (5.6%), Latinx (4.0%), multiple races (2.2%), and other (0.7%). Participants were randomly assigned to read a trial summary involving a military veteran with PTSD, diagnosed 1 or 5 years prior to trial, and then make juror decisions. Results ANOVA examined how PTSD diagnosis timing influenced jurors' perceptions of the influence of defense arguments on their verdict. A significant main effect of diagnosis timing was found on perceived influence, F(1,353) = 6.34, p = .01. Jurors rated defense arguments as more influential when the PTSD diagnosis was made 1 year before the trial (M = 51.72) than 5 years earlier (M = 44.36). Conclusion The results show that jurors’ perceptions of a veteran defendant are influenced by the timing of the PTSD diagnosis, with recent diagnoses making defense arguments more persuasive. Specifically, PTSD diagnosed close to trial may be viewed as affecting neuropsychological processes, including memory and emotion regulation, that could impact criminal behavior. This neuropsychological conceptualization could alter jurors' perceptions of the defendant’s behavior, producing the main effect for PTSD diagnosis timing. The findings suggest that defense attorneys should consider PTSD diagnosis timing when crafting their arguments, as it can shape jurors’ views on the defendant's neuropsychological functioning and criminal responsibility.