Appelbaum said the government's use of civil commitment of sexual offenders raises a host of questions, not the least of which involves the questionable efficacy of "therapy" for sexual offenders. "For psychosis, for instance, we know what to do as clinicians and have some reasonable prospect that conditions will be improved," he said. "For sexually dangerous offenders, the data are much weaker, and such treatments as exist haven't become part of the psychiatric mainstream."