Selected States were California, Arizona, Texas, Iowa, New York, and Massachusetts. Results indicate almost no change over time in the proportion of prisoners with prior State mental hospital experiences. However, there was a consistent change in the characteristics of mental patients coming into the system, with the 1978 patients showing more arrests and more prior hospitalizations. Among patients coming into the mental health system in 1968, 12 percent were confined for violent offenses, while 63 percent were confined for nuisance offenses. In 1978, 20 percent of patients were confined for violent offenses, while only 38 percent were confined for nuisance offenses. In addition, the proportion of mental patients with prior arrests nearly doubled between 1968 and 1978, while the proportion of offenders with prior hospitalizations remained constant. While results suggest that there has been a shift of clientele from the criminal justice system to the mental health system, it is likely that the major impact of deinstitutionalization policies has been at the local, rather than the State, level. 4 tables, 1 note, and 12 references.