Preventing Crime through Selective Incapacitation

Making the length of a prison sentence conditional on an individual’s offense history is shown to be a powerful way of preventing crime. Under a law adopted in the Netherlands in 2001, prolific offenders could be sentenced to a prison term that was some ten times longer than usual. We exploit quasi-experimental variation in the moment of introduction and the frequency of application across 12 urban areas to identify the effect. We find the sentence enhancements to have dramatically reduced theft rates. The size of the crime-reducing effect is found to be subject to sharply diminishing returns.