FOLLOWING PASSAGE IN CALIFORNIA OF THE LANTERMAN, PETRIS, SHORT (LPS) ACT OF 1968, MANY INMATES RESIDING IN PSYCHIATRIC STATE INSTITUTIONS WERE RELEASED TO COMMUNITY-BASED PROGRAMS. DESPITE MANY BENEFITS OF THIS REFORM, AN UNDESIRED EFFECT BECAME APPARENT: MANY OF THESE DEINSTITUTIONALIZED PERSONS BECAME CAUGHT IN THE CRIMINAL JUSTICE SYSTEM AND WERE LATER BROUGHT TO COURT ON CRIMINAL CHARGES. A STUDY OF ALMOST 500 DEFENDANTS IN NEED OF PSYCHIATRIC TREATMENT INDICATES THAT THE OFFENSES OF THESE MENTALLY DISORDERED DEFENDANTS, WHETHER MINOR THREATS TO PUBLIC PEACE OR SERIOUSLY HARMFUL PERSONAL ASSAULTS, GENERALLY DERIVE FROM ACUTE PSYCHOTIC PROCESSES OR FROM POOR JUDGMENT AND IMPULSIVE BEHAVIOR THAT ATTENDS CHRONIC MENTAL ILLNESS. ABOUT HALF THE OFFENSES ARE MISDEMEANORS AND HALF ARE FELONIES. SOME OF THE DEFENDANTS HAVE PRIOR ARRESTS BUT FEW HAVE SERVED TIME IN A STATE PRISON. ALL, HOWEVER, HAVE PSYCHIATRIC HISTORIES OF FROM 1 TO 15 PSYCHIATRIC HOSPITALIZATIONS; THE AVERAGE IS MORE THAN 3 PRIOR ADMISSIONS. ALSO, DESPITE THE LONG MEDICAL HISTORY, ALMOST 60 PERCENT HAVE NO HAD OUTPATIENT TREATMENT. THE 40 PERCENT WHO HAD BEEN SEEN AT A LOCAL CLINIC MADE ONLY SPORADIC CONTACTS. AT THE TIME OF ARREST, 94 PERCENT WERE NOT INVOLVED IN ANY OUTPATIENT PROGRAM. ALTHOUGH COMMUNITY SERVICES ARE OFFERED TO THE CHRONICALLY MENTALLY ILL, ONE DISTINCT, IDENTIFIABLE, AND HOMOGENEOUS GROUP OF CHRONIC OUTPATIENTS DOES NOT USE THEM. THIS 'FORFEITED' GROUP NEEDS SERVICES TO MOST BUT ARE LEAST ABLE TO SECURE THEM. THESE PERSONS ARE LIKELY TO FORGET THE TIME OF THEIR APPOINTMENTS OR THE PERSON THEY ARE SUPPOSED TO SEE; STOP TAKING THEIR MEDICINE BECAUSE THEY ARE CONVINCED IT IS THE SOURCE OF THEIR PROBLEMS; AND SPEND THEIR MEAGER INCOME IN A FEW DAYS AND HAVE NOTHING LEFT FOR THE REST OF THE MONTH. THREE FACTORS CONTRIBUTE TO THIS SITUATION AND ULTIMATELY TO THEIR ARREST AND PROSECUTION: (1) PROGRAMMATIC FACTORS (CHARACTERISTICS OF THE INPATIENT AND OUTPATIENT SERVICES), (2) CLINICAL FACTORS (CHARACTERISTICS OF THE POPULATION), AND (3) LEGAL FACTORS (THE COMMITMENT STANDARD OF DANGEROUSNESS AND THE RIGHT TO REFUSE TREATMENT). THESE FACTORS ARE ANALYZED IN DETAIL AND SOME SOLUTIONS TO THE PROBLEM ARE OFFERED. REFERENCES ARE PROVIDED. (PRG)