This paper provides an extended supply of labour model which allows for different intensities of legal and illegal (criminal) activities and in which criminal activities may be considered both as work and leisure. Heterogeneity of individuals is also taken into account. The model is estimated from Finnish aggregate time-series data, pooled Finnish municipalities data and pooled international cross-country data. With the Finnish aggregate data, a volume index of crime is constructed and then used in testing the model. All empirical results give strong support to the hypothesis that apprehension and punishment are important deterrents of crime. By contrast, the role of sosioeconomic and demographic variables turns out to be of little importance.