COURT SUPERVISED JUVENILES IN LOS ANGELES COUNTY ARE CATEGORIZED UNDER THREE SECTIONS OF THE WELFARE AND INSTITUTIONS CODE: (1) SECTION 600, REFERRING TO MINORS WHO ARE WITHOUT PROPER PARENTAL CARE OR CONTROL OR ARE VICTIMS OF ABUSE; (2) SECTION 601, REFERRING TO STATUS OFFENDERS; AND (3) SECTION 602, REFERRING TO 'TRUE' DELINQUENTS OR JUVENILES WHO HAVE VIOLATED THE PENAL CODE. LOS ANGELES COUNTY CURRENTLY DOES NOT ALLOW MIXING THESE THREE GROUPS OF MINORS TOGETHER IN DETENTION FACILITIES. JUVENILES UNDER SUPERVISION OF THE LOS ANGELES COUNTY PROBATION AND PUBLIC SERVICES DEPARTMENTS DETAINED IN THREE INSTITUTIONS WERE TESTED, AND THE RESULTS WERE COMPARED AND EVALUATED TO DETERMINE IF DIFFERENCES EXIST IN DELINQUENCY PRONENESS AMONG THE THREE GROUPS. THE DATA SEEMED TO INDICATE THAT DIFFERENCES IN DELINQUENCY PRONENESS DO EXIST FOR THE THREE COURT-SUPERVISED GROUPS. MINORS DETAINED FOR STATUS CRIMES TENDED TO SCORE SLIGHTLY HIGHER IN PRONENESS THAN THE MINORS ACCUSED OF MORE SERIOUS LAW VIOLATIONS. HOWEVER, THE DIFFERENCES MAY NOT BE SIGNIFICANT, SINCE THE NUMBER OF STATUS OFFENDERS TESTED WAS SMALL. THE GROUP OF ABUSED AND NEGLECTED JUVENILES SHOWED MORE DELINQUENCY PRONENESS THAN THE CONTROL GROUP COMPOSED OF HIGH SCHOOL STUDENTS. THE RAW SCORES FOR THE MINORS IN PLACEMENT WERE ONLY SLIGHTLY LESS NEGATIVE THAN THE CONTROL GROUP, INDICATING A LESSENING OF DELINQUENCY PRONENESS AFTER PLACEMENT. IT IS MAINTAINED THAT, WHILE CERTAIN DIFFERENCES MAY EXIST AMONG THE THREE CATEGORIES OF COURT-SUPERVISED MINORS, THESE DIFFERENCES CANNOT BE ASSUMED TO RESULT IN ANY SET OF BEHAVIOR PATTERNS, BE INDICATIVE OF THE TYPE OF CARE AND TREATMENT NEEDED, OR BE AS CONCISE AS THE LEGAL CODE SECTIONS IMPLY. THE TREATMENT AND REHABILITATION NEEDS OF THE GROUPS DEPEND ON THE INDIVIDUAL MINOR, AND THE SEPARATION OF THESE JUVENILES IN NONSECURE PLACEMENT FACILITIES SHOULD BE ON THE BASIS OF INDIVIDUAL NEED. STUDY DATA AND REFERENCES ARE PROVIDED. (DAG)