"The legislature directed the Washington State Institute for Public Policy (Institute) to evaluate the costs and benefits of certain juvenile and adult criminal justice policies, violence prevention programs, and other efforts to decrease particular 'at-risk' behaviors of youth."
With regard to adult offender drug treatment programs, it found, "Generally, drug treatment for adult offenders works to lower criminal recidivism rates. The degree to which recidivism is reduced is not large—single digit, not double digit, percentage reductions in recidivism rates should be expected. Nonetheless, with treatment typically costing about $2,500 per participant, the net economics of drug treatment appear positive, on average. The programs roughly break even from a taxpayer-only perspective and, including the benefits crime victims receive when recidivism rates are reduced, the programs typically produce about three dollars in benefits per dollar of cost."

Click here for complete datatable of Benefit to Cost Ratios of Adult Drug Treatment Programs.

Source

Aos, Steve; Phipps, Polly; Barnoski, Robert; Lieb, Roxanne, "The Comparative Costs and Benefits of Programs to Reduce Crime," Washington State Institute for Public Policy (Olympia, WA: May 2001), pp. 1, 23-26.
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