Abstract
This Article uses internal memoranda and emails to describe the efforts of the California Department of Mental Health to suppress a serious and well-designed study that showed just 6.5% of untreated sexually violent predators were arrested for a new sex crime within 4.8 years of release from a locked mental facility. The Article begins by historically situating sexually violent predator laws and then explains the constitutionally critical role that prospective sexual dangerousness plays in justifying these laws. The Article next explains how the U.S. Supreme Court and the highest state courts have allowed these laws to exist without requiring any proof of actual danger. It then describes the California study and reconciles its findings with those of a well-known Washington study by explaining the preventive effects of increasing age. Finally, the Article explains how these results undermine the justification for indeterminate lifetime commitment of sex offenders.