Co-offending and the diversification of crime types.

There is theoretical and empirical support for co-offending being important not only for understanding current offending but also subsequent offending. The fundamental question is--why? In this article, an aggregate analysis is performed that begins to answer this question. Disaggregating solo- and co-offending by single year of age (12-29 years) and crime type in a largely metropolitan data set from British Columbia, Canada, 2002 to 2006, it is shown that the distribution of co-offences is significantly more varied than the distribution of solo offences. This more varied distribution of co-offences favors property crimes during youth but fades as offenders age.