Prior research has demonstrated that school disciplinary practices lead to juvenile justice intervention or the “school-to-prison pipeline” and that juvenile justice intervention leads to adversities, including drug-using behavior, in adolescence and adult life. Yet, it is not clear which form of official intervention, school suspension, and expulsion or police arrest, is more predictive of drug use among young people. Using data from the Rochester Youth Developmental Study, we examined both the immediate, concurrent influence of school and police intervention on drug use during adolescence and the long-term, cumulative impact of school and police intervention during adolescence on subsequent drug use in young established adulthood. The results indicate that school exclusionary practices appeared to be more predictive of drug use than police arrest during both adolescence and young adulthood. Additionally, such negative effects mainly exhibited among minority subjects, and the effects by gender appeared contingent on developmental stages.