Samenvatting

The introduction in the Netherlands of the SOV measure in 2001, followed by the ISD Order in 2004, opened the opportunity for the courts to incarcerate systematic offenders, mostly addicts, for a period of two years. During the period of imprisonment convicted are offered various programs to kick their habits and tackle their other problems. The article assesses the social costs and benefits of the SOV/ISD measure. The analysis takes account of the improvement in general health and productivity of the participants, and models the crime reduction effects through special prevention, incapacitation and general deterrence. Substituting results from the first effectiveness study of the SOV program, which by the way only covers one follow-up year, it is calculated that the SOV/ISD measure may yield a positive net result of as much as € 4 million per participant.