Analysis of arrest documents indicates that police routinely invoked labels of mental illness and dangerousness, and that they recommended psychiatric assessment in a third of the cases that eventuated in clinical remands. A significant relationship was found between police judgments and clinical assessments concerning the dangerousness of defendants. Police reports on forensic patients showed a tendency for the arresting officer to recommend psychiatric assessment as a vehicle for ensuring the dual application of judicial and therapeutic intervention. Police records were replete with moral assessment about mentally disordered defendants and with a number of strategies designed to influence subsequent decisions of other legal and psychiatric authorities. In this study, police functioned as forensic gatekeepers, alerting clinicians and other officials to signs of mental disorder and criminality and to appropriate courses of action. At the initial point of arrest, the police assisted in laying the groundwork for the subsequent institutional careers of medicolegal subjects. 44 references. (Author abstract modified)