Trends in drug use and criminal charges of 44,223 consecutive admissions to the District of Columbia Superior Court lock-up between December 1971 and April 1975 were analyzed. While the number of persons arrested and admitted to the lock-up remained relatively constant during this time, drug use as measured by positive urinalysis declined substantially in 1973 and remained at a lower level through 1975. Heroin use showed a decline similar to the overall trends in 1973, but began to increase in mid-1974. Arrestees who were drug positive were generally less likely to be charged with major crimes of violence than those who were drug negative. Exceptions to this pattern as well as trends in drug use and crime in the arrested population are discussed.