Data for 70 detainees were incomplete, thus main analyses focus on only 252 youth. Overall, 19 to 39 percent of the 323 youth reported physical abuse and 20 percent reported sexual victimization experiences. Voluntary participation rates were high (90 percent or more), but cooperation is likely to be greatest in nonadversarial, confidental circumstances where youth believe in the value of urinalysis. In such circumstances, there is a respectable correspondence between urinalysis results and self-reported marijuana/hash hish use. Youths whose urine tests were drug positive for marijuana/hash hish had a significantly larger number of referrals for nondrug felony offenses than did drug-negative youth, while youth who tested drug negative but reported drug use had similar court referral histories but higher sexual victimization rates. These two groups also were more likely to be older and white than youth who tested drug-negative and denied marijuana/hash hish use. Results suggest the utility of both voluntary urinalysis and self-report drug use data and have implications for practice and future research. 4 tables, 2 notes, and 38 references.