What Works to Reduce Violent Gun Crime in Focused Deterrence Initiatives? Estimating the Effect of Services and Enforcement in Facilitating Desistence Among Prolific Violent Offenders

ABSTRACT

One of the most promising evidence-based approaches to targeted and preventative intervention for gun violence is focused deterrence (FD), which is part of the Project Safe Neighborhoods (PSN) suite of community-and policing-based violence prevention initiatives. Though evaluations of FD initiatives generally find positive violence reduction effects, there remain several conspicuous gaps in our understanding of the generalizability of FD, and the mechanisms underlying the program, which prevent us from more fully maximizing its potential utility for crime reduction. First, the marginal effect of costly enhanced enforcement and sanction options in FD programs, above and beyond programs with only service provisions, is unclear. Second, heterogeneity in program treatment effects due to either variation in the type of intervention or type of targeted individuals is not well quantified. Third, the nature of most FD evaluations, which concentrate on the estimation of the overall program treatment effect, preclude a deeper understating of mechanisms in play that explain ‘why’ the intervention is effective. To address these issues, this study will provide new scholarly and policy-relevant evidence on the effectiveness of FD interventions across contexts and different manifestations, and the mechanisms underlying the effects, for the goal of developing more efficient and effective interventions. The study will work in partnership with the Tampa Police Department (TPD), United States Attorney’s Office (USAO), and Safe & Sound Hillsborough (S&S), our law enforcement, prosecutorial, and community-service provider partners, respectively, to undertake the three elements of FD: (1) identifying prolific violent offenders, (2) communicating and implementing enhanced enforcement and sanctions, if necessary, and (3) offering and providing social services in the community to all participants, if desired. By conducting a randomized control trial assigning different interventions, we seek to a) estimate a marginal treatment effect of enhanced enforcement and sanctions above and beyond a treatment effect that is due to service provisions only, and provide benefit-cost analysis for these different options, b) quantify heterogeneity in treatment effects across program type and target group, and c) conduct a survey to better understand how subjective beliefs about risk, costs, rewards, and procedural justice are affected by such interventions to better understand underlying mechanisms of effectiveness. Moreover, the study will build upon recent evaluation studies conducted with the TPD and Pasco County (FL) Sheriff’s Office on the mechanisms and effects associated with FD and PSN initiatives, to address these questions and combat the rise in violence and gun crime in Tampa.