Escalation in offending: a growth mixture modelling approach with two temporal scales

Escalation/de-escalation of offending is an important topic for policy, but has been comparatively neglected in criminal careers research. A difficulty has been identifying appropriate methodology. In an earlier presentation on escalation we identified that two temporal scales need to be considered - the first representing age and the second representing the number of convictions. In this earlier work we used a linear mixed-effects model on crime seriousness. The results suggested that ageing is associated with de-escalation whereas the number of conviction occasions is associated with escalation, with the two processes pulling in different directions. This presentation will instead examine the hypothesis that there are different types of underlying criminal escalation across offenders. We have developed a growth mixture model which takes into account both temporal scales in order to understand both individual crime growth curves and to distinguish latent types of crime development. The study is based on a 1953 birth cohort of offenders in England and Wales.