AT THE TIME OF THIS STUDY (1967), THERE WERE FEWER THAN 10 JAPANESE-AMERICAN ADULTS IN CALIFORNIA PRISONS AND FEWER THAN 10 YOUTHS IN CALIFORNIA YOUTH AUTHORITY CAMPS. HISTORICALLY, JAPANESE AMERICANS HAVE HAD THE LOWEST CRIME RATE OF ANY ETHNIC GROUP. TO IDENTIFY POSSIBLE REASONS FOR THIS FACT, A GROUP OF 25 YOUTHS FROM THE CULTURE WHO WERE ON PROBATION IN CALIFORNIA WERE COMPARED WITH 37 JAPANESE-AMERICAN NONDELINQUENTS. STRUCTURED INTERVIEWS WERE USED TO GATHER DATA. THE DELINQUENTS DIFFERED FROM THE NONDELINQUENTS IN THEIR HOME LIFE, IN THEIR ETHNIC RELATIONSHIPS, AND IN THE INTERNALIZATION OF ETHNIC CONCEPTS. WHILE DIVORCE IS RARE IN JAPANESE-AMERICAN HOMES, A THIRD OF THE DELINQUENTS CAME FROM BROKEN HOMES. A LARGER PROPORTION OF THE DELINQUENTS WERE DISSATISFIED WITH HOME LIFE AND WISHED TO LEAVE. A LARGER PROPORTION ALSO ASSOCIATED WITH NON-JAPANESE PEERS AND DATED GIRLS FROM OUTSIDE THE ETHNIC GROUP. THE MAJORITY OF PARENTS OF DELINQUENTS FELT DISSATISFIED WITH THEIR OWN UPBRINGING AND HAD TRIED TO REAR THEIR OWN CHILDREN DIFFERENTLY. A LARGER NUMBER OF DELINQUENTS FELT THAT ONE HAD TO 'PROVE' MANHOOD WHILE MOST OF THE NONDELINQUENTS FELT ONE GREW INTO MANHOOD, A STRONG ETHNIC IDEAL. BOTH PARENTS AND DELINQUENTS WERE DISSATISFIED WITH SCHOOLS, THE NEIGBORHOOD, AND SOCIAL CONTACTS. IT IS SUGGESTED THAT THE STRONG SOCIAL CONTROL OF THE JAPANESE-AMERICAN CULTURE IS A STRONG CRIME DETERRENT. THE ETHNIC SCHOOL SYSTEM, THE ETHNIC ECONOMIC AND SOCIAL WELFARE SYSTEM, AND THE ETHNIC VOLUNTARY AND SOCIAL OPPORTUNITY SYSTEM ARE STRONG REINFORCERS OF ETHNIC VALUES. THOSE IN THIS STUDY WHO WERE DELINQUENTS WERE MARGINAL MEMBERS OF THIS SYSTEM AND LESS RESPONSIVE TO ITS STRONG CONTROL. (GLR)