"Importantly, Belenko et al. (2005) have shown just the opposite result for DTAP [Drug Treatment Alternative to Prison]: 57% of DTAP participants were rearrested for any offense at least once in the follow-up period compared with 75% of the comparison group. Similarly, only 42% of DTAP participants were reconvicted of any offense compared with 65% of the prison comparison group. Finally, only 30% of the DTAP participants had a new jail sentence (compared with 51% of prison comparisons) and only 7% had a new prison sentence (compared with 18% of prison comparisons).
"When these outcomes are monetized, our study shows that the DTAP program is cost beneficial from the CJS [criminal justice system] perspective; it is less costly to divert drug abusing offenders to treatment instead of prison. In addition, the findings suggest that a long-term perspective is important in evaluating treatment diversion or other criminal justice-based treatment programs. We find that benefits increase in each subsequent year of analysis. Findings from this analysis provide an economic justification for the DTAP program. In addition, our unit cost estimates for the CJS and diversion expenses for New York City may be used by policymakers and researchers to evaluate other diversion programs."
Zarkin, Gary A., Laura J. Dunlap, Steven Belenko & Paul A. Dynia, "A Benefit-Cost Analysis of the Kings County District Attorney's Office Drug Treatment Alternative to Prison (DTAP) Program," Justice Research and Policy, Vol. 7, No. 1 (Washington, DC: Justice Research and Statistics Association, 2005), p. 20.