THE MALE ADOLESCENTS WERE DIVIDED INTO FOUR GROUPS ACCORDING TO RACE (BLACK VERSUS WHITE) AND LEVEL OF ASSAULTIVENESS (HIGH VERSUS LOW). A HIGH ASSAULTIVE PRISONER WAS DEFINED AS AN INDIVIDUAL WHO HAD A LIFETIME HISTORY OF ENGAGING IN PHYSICAL VIOLENCE AND ASSAULTIVENESS. A LOW ASSAULTIVE INDIVIDUAL, ALTHOUGH COMMITTED TO A PENAL INSTITUTION, WAS JUDGED BY BOTH GUARDS AND OTHER PRISONERS AS NONASSAULTIVE AND THERE WAS ALSO A LACK OF VIOLENCE IN HIS SOCIAL HISTORY. THE AVERAGE AGE OF SUBJECTS WAS 18.5 YEARS. EACH SUBJECT WAS EVALUATED USING SCALES RELATED TO HOSTILITY, INTROVERSION, INTROVERSION-EXTROVERSION, AND PERSONALITY MEASURES CONTAINED IN THE MINNESOTA MULTIPHASIC PERSONALITY INVENTORY (MMPI). THE NEED TO IDENTIFY VIOLENT INDIVIDUALS ACCURATELY, EITHER FOR REHABILITATION OR SOCIAL CONTROL, LED TO THE USE OF THE MMPI AND OTHER TESTS AS PREDICTORS. SIGNIFICANT RESULTS OF THE STUDY WERE AS FOLLOWS: (1) BLACK LOW ASSAULTIVES HAD HIGHER SCORES OF ALL GROUPS; (2) LOW ASSAULTIVES HAD HIGHER SCORES THAN HIGH ASSAULTIVES; (3) WHITE HIGH ASSAULTIVES HAD THE LOWEST SCORES, AND ALL SCORES WERE WITHIN THE HETEROSEXUAL RANGE; (4) HIGH ASSAULTIVES HAD LARGER SCORES THAN LOW ASSAULTIVES, WITH WHITE HIGH ASSAULTIVES HAVING LARGER SCORES THAN EVERYONE; AND (5) GROUP SCORES SUGGESTED THAT ALL INDIVIDUALS WERE PAROLE VIOLATION RISKS. RESEARCH ON THE VIOLENT PERSONALITY USING THE MMPI IS STILL INCONCLUSIVE, HOWEVER, AND OFTEN CONTRADICTORY. THE HOSTILITY SCALE DEVISED BY BUSS AND DURKEE MAY BE MORE VALUABLE IN ASSESSING THE VIOLENT PERSONALITY. SUPPORTING DATA AND REFERENCES ARE PROVIDED. (DEP)