Abstract

Assessing offenders' risk of future violent behavior continues to be an important yet controversial role of forensic psychologists. A key debate is the relative effectiveness of assessment methods. Specifically, actuarial methods (see Quinsey et al., 1998 for a review) have been compared and contrasted to clinical and structured clinical methods (see e.g. Hart, 1998; Webster et al., 1997). Proponents of each approach argue for its superiority, yet validity studies have made few formal comparisons. In advancing the available research, the present study examines systematically the type of forensic case (i.e., sexual violence versus nonsexual violence) and type of assessment method (i.e., actuarial, structured clinical, and unstructured clinical). As observed by Borum, Otto, and Golding (1993), forensic decision making can also be influenced by the presence of certain extraneous clinical data. To address these issues, psychologists and doctoral students attending the American Psychology Law Society conference were asked to make several ratings regarding the likelihood of future sexual and nonsexual violence based on data derived from actual defendants with known outcomes. Using a mixed factorial design, each of these assessment methods were investigated for its influence on decision-makers regarding likelihood of future violence and sexually violent predator commitments. Finally, the potentially biasing effects of victim impact statements on resultant decisions were also explored.