Objectives: To explore differences in government costs among several subpopulations of offenders who were eligible to participate in California’s Proposition 36, enacted as the Substance Abuse and Crime Prevention Act of 2000 (SACPA).
Methods: The study compared a time-lagged cohort of offenders meeting SACPA eligibility criteria before SACPA was enacted (N=42,706) to the first-year SACPA cohort (N=37,991). Difference-in-differences (DID), multilevel, multivariate, random-effects regression models that included membership in the subpopulation categories (criminal, mental health, employment) and interaction terms were estimated separately for men and women to determine the effect of SACPA on total costs and across eight cost domains (prison, jail, probation, parole, health, arrests, convictions, and treatment).
Results: A substantial proportion of SACPA participants had significant chronic problems. SACPA-eligible male offenders with extensive criminal histories yielded greater DID savings than low-history offenders, an effect augmented by SACPA participation. Among female offenders with extensive criminal histories, overall savings were negated by increased arrest/conviction costs. A documented history of mental illness resulted in increased costs for men and women.
Conclusions and implications for practice: SACPA participation was cost-effective among more severe cases, especially for male offenders with extensive criminal histories; however, the program did not attenuate increased costs for offenders with severe mental illness. Services for the special needs of such offender populations need further development and implementation.