Evaluating National and State Policies to Prevent Antisocial Behavior and Incarceration

Introduction: This paper describes work being completed in the state of Victoria, Australia that is integrating longitudinal, program effectiveness and epidemiological data to develop a proposal to prevent state incarceration and crime rates. The paper will report Victorian data to: 1) describe rates of antisocial behavior from ages 10-25 years; 2) examine effect sizes for associations between modifiable risk factors and subsequent antisocial behavior; and 3) estimate the return-on-investment in Victoria a $AUS150 million investment (20% of the planned prison budget) would have in a mix of five evidence-based prevention strategies. The project uses longitudinal data from the International Youth Development Study (IYDS). Prior analyses have shown that risk factors in Victoria have generally comparable predictive effects on youth antisocial behavior to those in age-matched cohorts in Washington State. This opens the way to apply selected parameters from the Washington State Institute for Public Policy return-on-investment models in Victoria.

Methods: Data from the IYDS comprised of 2,884 Victorian students and 2,885 Washington State students when recruited in 2002 and followed-up to 2004. Analyses presented here focus on Victorian students. Victorian students also have been followed-up from 2006-2008 and in 2010 and 2012. Participants completed the Communities that Care Youth Self-Report Survey that included measures of risk and protective factors across relevant domains in a young person’s life, as well as antisocial behavior, arrests, and incarcerations. Retention rates have exceeded 80%.

Results: The most prevalent antisocial behaviors from ages 10-25 years in this Victorian sample were acts intended to cause physical injury (8%-13%), theft (0.1-18%), and public order offences (1-30%). Associations between the risk factors of community inequality, family conflict and parenting, school, and alcohol availability and early age alcohol use on the one hand and later antisocial behavior will be examined to generate effects sizes to inform return-on-investment calculations. The return-on-investment for five strategies selected to address the above-listed risk factors (Nurse-Family Partnerships, Triple P Positive Parenting Program, tutoring by peers and adults, youth mentoring, strategies to reduce alcohol availability and early age alcohol use) will be calculated.  

Conclusions: Recommendations will be made regarding cost-effective prevention approaches for antisocial behavior in the Victorian context and these will be disseminated to Victorian policy makers.