Penal special measures were an important part of Norwegian penal law up until the 1970s. First, in some areas it is reasonable to say that the abolitionist critique had an impact on the shaping of the system of preventive detention. The guarantees of the rule of law in preventive detention have thus been strengthened. And it is particularly in this area that there appears to be challenges to the rule of law in the practice of today's system of preventive detention. Special measures were particular initiatives instituted for offenders, initiatives going beyond the regular punishments such as fines or prison sentences. In Norway, the special measures of forced labor for vagrants, reform school for young offenders, as well as preventive supervision for mentally deviant offenders thought to be at risk for recidivism. There was a condition for a sentence of preventive supervision that the offender had been subjected to a forensic psychiatric evaluation and diagnosis.