Expert psychological testimony on dangerousness is a key element in the trials of sexually violent predators (SVPs). These trials allow for the indeterminate civil confinement of sexual offenders after they have completed their incarceration, based on whether offenders suffers from a statutorily described mental illnesses and whether they are likely to be a continuing danger to society. To date, only one experimental study has examined the impact of psychological expert testimony on juror decision-making in this context. The present studies are designed to build on the PI's previous theoretical and experimental work investigating the effects of psychological expert testimony on dangerousness in capital sentencing and extend it to sexual violent predator adjudications. Previous research found that mock jurors were more influenced by less scientific expert testimony and that standard adversary procedures did not remove this bias. Additional research suggested that Epstein's Cognitive Experiential Self theory (CEST) may offer an explanation for this bias, and means to counteract jurors' bias allowing jurors to more appropriately weigh more scientific testimony. For the present studies, three types of psychological expert testimony (i.e., pure clinical, actuarial, and guided professional judgment) will be created based on real trial transcripts, and will be transformed into a scripted videotape simulation. This simulation will be presented to both college student mock jurors and more representative juries who will deliberate in their decision-making. The ability of jurors and juries to properly weight the manipulated expert testimony throughout the trial process will be assessed, and the effectiveness of CEST theory, legally practical CEST manipulations, and pre-existing personality characteristics to affect juror decision-making will be measured The proposed research will have broad impact on undergraduate teaching, the college, underrepresented groups' involvement in research, the psychological and legal research communities, and society. Undergraduates will be primarily responsible for collecting the data for these experiments, and an advanced psychology and law class (psych 190) will use this research program as its main topic. Student authored presentations at major conferences will likely result from this student participation, an extraordinary opportunity for students at a primarily teaching-focused institution. The project investigators will disseminate the results of this study broadly to the psychological and legal community through law reviews and peer reviewed scientific journals, and presentations at interdisciplinary conferences. The studies results will have a substantial impact in the psychological community, informing the existing debate concerning appropriate evaluative tools for dangerousness evaluations and informing the theoretical literature on how jurors process expert testimony.