Of the 6,000 defendants tested for drug use between June 1984 and January 1985, just over half had used drugs shortly before their arrest. Cocaine use has increased dramatically since 1984, and PCP and opiates were major drug abuse problems among arrestees. Rates of PCP use were highest for defendants aged 18-21; rates of opiate and cocaine use increased until ages 31-35 and then declined. Women, who comprised 18 percent of all arrestees, had the same overall rate of drug use (52 percent) as men. Pretrial rearrest rates were 50 percent higher for drug users than for nonusers, and users of two or more drugs were more likely to be rearrested before trial than users of only one drug. Defendants who used drugs shortly before arrest were placed in a program that required them to appear for periodic urine tests. These defendants had lower rates of pretrial rearrest than defendants referred to drug abuse treatment or released without special conditions. Failure to comply with program requirements could result in court sanctioning. 6 data exhibits. (Author summary modified)