Offending Trajectories in a New Zealand Birth Cohort*

In this paper, we develop a latent class modeling method to examine variation in offending trajectories. This model is applied to test the predictions of the trajectory theories developed by Moffitt and Patterson that offending history data can be classified into early onset/life‐course‐persistent offending and late onset/adolescent‐limited offending trajectories, with these trajectory groups being related to different etiological factors. The approach was applied to data gathered over the course of a longitudinal study of more than 900 New Zealand children studied from birth until the age of 18. The analysis identified four trajectory groups, with these trajectory groups corresponding to nonoffenders, moderate risk offenders, adolescent onset offenders, and chronic offenders. The adolescent onset and chronic offender groups were similar to the trajectory groupings predicted by the Moffitt/Patterson theories. Examination of social, family, childhood, and peer factors associated with these offending trajectories suggested the presence of a series of common etiological factors relating to family functioning and early adjustment that discriminated between the trajectory groups. However, evidence of trajectory‐specific etiology also existed, in which the formation of deviant peer affiliations for young people from moderate risk backgrounds led to the rapid onset of offending in adolescence.