New York State's Criminal Procedure Law (CPL), which operated until April 1974, mandated psychiatric predictions of dangerousness for all indicted felony defendants found incompetent to stand trial. These psychiatric assessments and ensuing judicial determinations dictated whether a defendant could be considered nondangerous and housed in a Department of Mental Hygiene facility or dangerous and housed in a Department of Correctional Service facility. The 154 dangerous defendants and the 103 nondangerous defendants were compared with respect to sociodemographic characteristics, criminal and hospitalization histories, patient careers through the mental and criminal justice systems, and some indicators of violent behavior in the hospital and in the community after release. The two groups were generally similar on sociodemographic characteristics and criminal and hospitalization histories. The most significant difference between the two groups was in the current alleged offense. A total of 83 percent of those charged with Class A felonies were determined dangerous by psychiatrists, whereas only 51 percent of those charged with other classes of felonies were found dangerous. However, following the determination of dangerousness, the two groups were almost exactly the same in terms of length of time hospitalized as incompetent, disposition of the offense, number of subsequent arrests, seriousness of subsequent arrests, number of subsequent mental hospitalizations, violence while subsequently hospitalized, or current status. Tables and two references are provided.