As in the majority of previous self-report studies, there were no significant offense differences by either race or SES for a global measure of hidden delinquency. Nonwhites, however, had a much higher mean number of serious offenses against the person than whites. Although some studies have suggested that the disproportionate involvement of nonwhites in serious crime based on official statistics reflects a law enforcement bias, the self-report data indicate this is not true. In investigating the relationship between official delinquency status and a series of self-reported delinquency measures, delinquents and nondelinquents were first compared in terms of the incidence of self-reported offenses and the prevalence of high-frequency offending. Second, official delinquency status was used as the dependent measure, with the self-report data used as predictors. Data indicate that the number of self-reported delinquent acts committed by official delinquents was significantly greater than for official nondelinquents. High-frequency offending, however, was no guarantee of having an arrest status. Overall, police statistics underestimated the extent of delinquency. Police data indicated a higher arrest rate for nonwhites, but as a group, nonwhites did not have consistently higher levels of self-reported delinquency. 16 tables. (Author summary modified)