Determining dangerousness in sexually violent predator evaluations: cognitive-experiential self-theory and juror judgments of expert testimony

Past research examining the effects of expert testimony on the future dangerousness of a defendant in death penalty sentencing found that jurors are more influenced by less scientific clinical expert testimony and tend to devalue scientific actuarial testimony. This study was designed to determine whether these findings extend to civil commitment trials for sexual offenders and to test a theoretical rationale for this effect. In addition, we investigated the influence of a recently developed innovation in risk assessment procedures, Guided Professional Judgment (GPJ) instruments. Consistent with a cognitive-experiential self-theory based explanation, mock jurors motivated to process information in an experiential condition were more influenced by clinical testimony, while mock jurors in a rational mode were more influenced by actuarial testimony. Participants responded to clinical and GPJ testimony in a similar manner. However, participants' gender exerted important interactive effects on dangerousness decisions, with male jurors showing the predicted effect while females did not. The policy implications of these findings are discussed.