Co-offending and the Persistence of Violence: A Dynamic Analysis

Objectives: Previous research underscores the influence of prior violent co-offending on subsequent violent behavior, linking it to a social contagion mechanism akin to the internalization of violence. However, these studies are limited by disregarding the entirety of a criminal career and overlooking diverse co-offending dynamics beyond co-offenders’ characteristics. This study examines the longitudinal impact of prior violent (solo and co-) offending on future individual-level violent behavior among Italian organized crime offenders. Methods: Leveraging criminal career data from 9819 Italian organized crime offenders, we model offending choices through a discrete-time Markov process. Subsequently, employing dynamic random-effects probit models, we quantify the influence of prior violent (solo and co-) offending on future violence, considering various confounders and unobserved individual-level effects. Results: Violence is a persistent and long-lasting behavior among organized crime offenders. Prior violent co-offending has a greater impact than prior violent solo offending on the probability of future violence. Prior violent co-offending increases the probability of future violent co-offending but does not impact the probability of future violent solo offending. Conclusions: The results show that co-offending promotes the transmission of violence but fail to support the internalization of violent behavior postulated by prior studies. We propose possible alternative mechanisms of violence transmission that operate through self-sustaining dynamics of violent co-offending within criminal groups. Although limited data on individual characteristics constrains interpretation, our results imply that violence transmission dynamics are independent from the individual characteristics of the co-offenders and more directly connected to group effects.