Research Findings

In February of 2005, the Government Accountability Office (GAO) issued its third report on the effects of adult criminal drug courts.1 Results from 23 program evaluations confirmed that drug courts significantly reduced crime. Moreover, although up-front costs for drug courts were generally higher than for probation, drug courts were found to be more cost-effective in the long run because they avoided law enforcement efforts, judicial case-processing and victimization resulting from future criminal activity.

In the ensuing years, researchers have continued to uncover definitive evidence for both the efficacy and cost-effectiveness of drug courts. The most rigorous and conservative estimate of the effect of any program is derived from "meta-analysis," in which scientists statistically average the effects of the program over numerous research studies. Four independent meta-analyses have now concluded that drug courts significantly reduce crime rates an average of approximately 7 to 14 percentage points.2  In some evaluations the effects on crime were as high as 35 percentage points. Importantly, the effects were greatest for "high-risk" offenders who had more severe criminal histories and drug problems. This suggests that drug courts may be best suited for the more incorrigible and drug-addicted offenders who cannot be safely or effectively managed in the community on standard probation.3 

Statewide evaluations have produced similarly impressive findings. A recent study of nine adult drug courts in California reported that re-arrest rates over a 4-year period were 29% for drug court clients (and only 17% for drug court graduates) as compared to 41% for similar drug offenders who did not participate in drug court.⁴ Another study of four adult drug courts in Suffolk County, MA, found that drug court participants were 13% less likely to be re-arrested, 34% less likely to be re-convicted and 24% less likely to be re-incarcerated than probationers who had been carefully matched to the drug court participants using sophisticated "propensity score" analyses.⁵  A recent long-term evaluation of the Multnomah County (Portland, OR) Drug Court found that crime was reduced by 30% over 5 years and effects on crime were still detectable an astounding 14 years from the time of arrest.⁶

In line with their effects on crime rates, drug courts have continued to prove cost-effective. One economic analysis in Washington State concluded that drug courts cost an average of $4,333 per client, but save $4,705 for taxpayers and $4,395 for potential crime victims, thus yielding a net cost-benefit of $4,767 per client.⁷ Another economic analysis in California concluded that drug courts cost an average of about $3,000 per client, but save an average of $11,000 per client over the long term.⁸  The Multnomah County Drug Court was found to cost less than business as usual for drug offenders, because probationers typically have multiple failed treatment experiences that are very expensive but elicit few gains. Factoring in cost-offsets from reduced arrests resulted in net savings of $6,744 per participant and $12,218 when victimization was also accounted for.⁹

Drug Courts Today
2,459 Drug Courts in operation as of December 31, 2009

• 1,317 Adult Drug Courts
  • *Of which 354 are Hybrid DWI/Drug Courts
• 476 Juvenile Drug Courts
• 322 Family Drug Courts
• 79 Tribal Drug Courts
• 172 Designated DWI Courts
• 5 Campus Drug Courts
• 29 Reentry Drug Courts
• 19 Veterans Courts

¹ U.S. Government Accountability Office. (2005). Adult drug courts: Evidence indicates recidivism reductions and mixed results for other outcomes [No. GAO-05-219]. Washington, DC: Author.

² Aos, S., Miller, M., & Drake, E. (2006). Evidence-based public policy options to reduce future prison construction, criminal justice costs, and crime rates. Olympia: Washington State Institute for Public Policy; Lowenkamp, C. T., Holsinger, A. M., & Latessa, E. J. (2005). Are drug courts effective: A meta-analytic review. Journal of Community Corrections, Fall, 5-28; Shaffer, D. K. (2006). Reconsidering drug court effectiveness: A meta-analytic review. Las Vegas, NV: Dept. of Criminal Justice, University of Nevada; Wilson, D. B., Mitchell, O., & MacKenzie, D. L. (2006). A systematic review of drug court effects on recidivism. Journal of Experimental Criminology, 2, 459-487.

³ E.g., Marlowe, D. B. (2006). Judicial supervision of drug-abusing offenders. Journal of Psychoactive Drugs, SARC Supplement 3, 323-331.

⁴ Carey, S. M., Finigan, M., Crumpton, D., & Waller, M. (2006). California drug courts: Outcomes, costs and promising practices: An overview of phase II in a statewide study. Journal of Psychoactive Drugs, SARC Supplement 3, 345-356.

⁵ Rhodes, W., Kling, R., & Shively, M. (2006). Suffolk County Court Evaluation. Cambridge, MA: Abt Associates.

⁶ Finigan, M., Carey, S. M., & Cox, A. (2007, April). The impact of a mature drug court over 10 years of operation: Recidivism and costs. Portland, OR: NPC Research, Inc.

⁷ Aos, supra, at p. 9.

⁸ Carey et al., supra, at p. 351.

⁹ Finigan et al., supra, at iv.