that same $1 million for more intensive community supervision (enough to monitor 125 high-risk parolees in the community).
To consider the example, suppose that the average prisoner would have, if released, five times the criminal activity rate (lambda) of the average high-risk probationer and that doubling probation supervision would cut crime among high-risk probationers by 10 percent. If the lambda of the high-risk probationer is x, incarceration would prevent 40 (5x) crimes per year, or 200x crimes, while intensive probation supervision would prevent 0.1 (1,000x) crimes per year, or 100x crimes. Thus, with the stated assumptions, prison is more cost-effective as crime control than probation. But, if intensifying probation would cut crime among high-risk probationers by 30 percent, intensive probation would be a more cost-effective use of that $1 million. It should be noted that this analysis can be done without monetizing the costs of crime (the benefits of crime control).3
In contrast, if the decision facing a lawmaker is whether to add $1 million to the corrections budget, there is a different set of questions than those above. One would need to know how much crime that sum would prevent, the value of that reduction to potential victims, and the nonbudget costs and non-crime-reduction benefits associated with that expenditure.
In thinking about how to assess desistance programs, it is critically important to keep in mind the heterogeneity of the population of released offenders: from those who have committed one nonviolent offense to those who may have served more than one sentence in prison for multiple violent offenses. Programs that may work for one kind of parolee may not work or even be appropriate to try for other groups. As but one example, Piquero and Pogarsky (2002) has argued that the threat of sanctions would be most ineffective on the two extremes of the offending spectrum, that is, those who either have extremely high self-control and those with very low self-control. Moreover, even for appropriate programs, poor program implementation is often a barrier to both program effectiveness and to program evaluation.
It is useful to think of the two obstacles (heterogeneity and implementation) in terms of the “demand” and “supply” for rehabilitation. Limited demand, that is resistance to change among parolees, limits what even the