THE FIRST STUDY WAS CONDUCTED TO DETERMINE WHETHER THE PD SCALE AND A VARIATION OF IT WOULD DISCRIMINATE BLACK CRIMINALS FROM BLACK NONCRIMINALS OF COMPARABLE AGE. CRIMINAL SUBJECTS WERE SELECTED FROM A COHORT OF 1,400 INMATES AT THE FEDERAL CORRECTIONAL INSTITUTION IN TALLAHASSEE, FLA. THE 120 SUBJECTS WHO MET SPECIFIED CRITERIA CONSTITUTED THE CRIMINAL SAMPLE, AND THEIR MEAN AGE WAS 20.4 YEARS. NONCRIMINAL SUBJECTS WERE UNIVERSITY STUDENTS. BLACK PRISON INMATES HAD SIGNIFICANTLY HIGHER MEAN SCORES ON BOTH SCALES THAN CULTURALLY DEPRIVED UNIVERSITY STUDENTS. THE SECOND STUDY WAS DESIGNED TO ASCERTAIN IF THE SCALES COULD DIFFERENTIATE LEVELS OF DEVIANCE FOR BLACK CRIMINAL AND STUDENT SAMPLES. RECORDS OF 102 PRISON INMATES WERE SURVEYED, WITH 50 SUBJECTS CLASSIFIED AS RECIDIVISTS AND 52 CLASSIFIED AS NONRECIDIVISTS. LEVELS OF DEVIANCE AMONG STUDENTS WERE DETERMINED BY MEANS OF AN ANONYMOUS QUESTIONNAIRE ADMINISTERED JUST BEFORE THE MMPI. RECIDIVIST PRISON INMATES HAD SIGNIFICANTLY HIGHER SCORES ON THE SCALES THAN FIRST OFFENDERS. AMONG STUDENTS, THERE WERE SIGNIFICANT DIFFERENCES IN THE EXPECTED DIRECTION AMONG SUBGROUPS WITH REGARD TO SELF-REPORTED DELINQUENCY. THE THIRD STUDY WAS CARRIED OUT TO EXPLORE THE ADEQUACY OF CONVENTIONAL T-SCORE NORMS FOR THE SCALES AND TO DETERMINE WHETHER THE USUAL CUTTING SCORE OF 70 HAD THE SAME IMPLICATIONS FOR BLACKS AND WHITES. THE MMPI PROTOCOLS OF TWO SAMPLES OF WHITE SUBJECTS WERE OBTAINED FROM AVAILABLE RESEARCH FILES. THE WHITE STUDENT SAMPLE WAS COMPRISED OF 60 MALES ENROLLED IN A PREDOMINANTLY WHITE UNIVERSITY. THE WHITE INMATE SAMPLE WAS SELECTED FROM A FEDERAL CORRECTIONAL INSTITUTION PROJECT AND INCLUDED 51 SUBJECTS. BLACK SUBJECTS HAD HIGHER SCORES ON THE SCALES THAN COMPARABLE SAMPLES OF WHITE SUBJECTS. ALTHOUGH THE THIRD STUDY WAS CONCERNED PRIMARILY WITH RACIAL BIAS, THE DATA ALSO REVEALED A SIGNIFICANT AGE BIAS ON THE SCALES. SUPPORTING TABULAR DATA AND REFERENCES ARE INCLUDED. (DEP)