An evaluation of periodic detention as an alternative to imprisonment

Abstract

The periodic, as opposed to the full time, detention of adult male offenders commenced in New Zealand in 1967. By 1977, more offenders were sentenced to a term of periodic detention than to imprisonment. The goal of this thesis is to evaluate the effectiveness of periodic detention as a penal measure, and more specifically, as an alternative to imprisonment. In devising a method whereby periodic detention could be evaluated, it was necessary to determine the objective of the penal measure. The prevention of reoffending was chosen as the penal objective, although with some stated reservations. The experimental procedure consisted of comparing the reoffending of subjects, subsequent to a term of imprisonment, to the reoffending of subjects subsequent to a term of periodic detention. The selection and allocation of appropriate subjects posed problems. In sentencing an offender to imprisonment for example, a judicial selection procedure has already occurred which may well be expected to bias the reoffending outcomes of prisoners in comparison to periodic detainees. In an attempt to establish a meaningful selection procedure, a control group was selected from a year prior to the introduction of periodic detention (1964) and an experimental group was selected from a year after the introduction of periodic detention. Strenuous attempts were made to ensure that the experimental group subjects selected for study were as similar as possible to the control group subjects. Thus the method allowed the comparison of the reoffending of two similar groups of offenders who had undergone vastly different penal measures, albeit at different points in time. The chronological differentiation of the two groups of subjects is acknowledged as a major, but necessary methodological flaw which would probably introduce bias into the reoffending results. The direction of the bias is considered in terms of speculative argument. It is predicted that the resulting bias would have the effect of increasing the reoffending of the experimental group in comparison to that of the control group. This prediction is not apparent however in the actual outcomes or results. Indeed the results, (a comparison of the offending of the subjects), indicate that there is no significant difference in the reoffending of subjects subsequent to a term of periodic detention in comparison to the reoffending of subjects subsequent to a term of imprisonment. It is argued that the rate of imprisonment in New Zealand is high, that some of the detrimental aspects of imprisonment are absent in periodic detention and that there are less social and financial costs for society to bear in relation to periodic detention. Given the lack of significant difference in the reoffending of the selected subjects subsequent to a term of periodic detention in comparison to a term of imprisonment, it is recommended that increased use could be made of periodic detention as an alternative to imprisonment.