One hundred two male inmates of county jail, randomly selected from those referred for psychiatric evaluation, were studied. Ninety percent had had psychiatric hospitalization; 92% had prior arrest records, 75% for felonies. Four fifths exhibited severe, overt psychopathology. More than three fourths met the criteria for involuntary hospitalization. When arrested, more than one third were transients and only 12% were employed. Thus, this population is characterized by extensive experience with both the criminal justice and mental health systems, severe acute and chronic mental illness, and poor functioning. More than half were currently charged with felonies and 39% with crimes of violence. We were also attempted to determine why inmates had been arrested rather than hospitalized and whether there has been "criminalization" of the mentally ill. There appears to be a need for more emphasis on ongoing involuntary treatment for this population.