Assessing the legal standard for predictions of dangerousness in sex offender commitment proceedings.

Advocates and courts legitimize sex offender commitment laws by claiming the laws confine only those who are “highly likely” to engage in sexual violence. This article proposes a definition of “probability” of future harm and assesses the legal probability thresholds commitment courts actually use. Using published information about recidivism and actuarial prediction, the authors concludes that moderate, but not extravagant, claims about legal probability thresholds are supportable but only on a rather optimistic set of assumptions. The authors recommend that sex offender commitment courts use the proposed methods to quantify judicial standards and findings about prediction. This will allow the claims for legitimacy to be more readily assessed.