Summary Research demonstrates that police reduce crime. We study this question by using a natural experiment in which a private university increased the number of police patrols within an arbitrarily defined geographic boundary. Capitalizing on the discontinuity in patrols at the boundary, we estimate that the extra police decreased crime in adjacent city blocks by 43–73%. Our results are consistent with findings from prior work that used other kinds of natural experiment. The paper demonstrates the utility of the geographic regression discontinuity design for estimating the effects of extra public or private services on a variety of outcomes.

In the last decade, a number of states have expanded the jurisdiction of their juvenile courts by increasing the maximum age to 18. Proponents argue that these expansions reduce crime by increasing access to the beneficial features of the juvenile justice system. Critics counter that the expansions risk increasing crime by reducing deterrence. In 2010, Illinois raised the maximum age for juvenile court for offenders who commit a misdemeanor. By examining the effect of this law on juvenile offenders in Chicago, this paper provides the first empirical estimates of the consequences of recent legislative activity to raise the age of criminal majority. Applying a difference-in-differences design with multiple control groups, we find little evidence of an effect. Our results suggest that-contrary to the expectations of both advocates and opponents-increasing the maximum age for juvenile court does not affect juvenile recidivism.

No abstract

The business improvement district (BID) is a popular economic development and urban revitalization model in which local property and business owners must pay an assessment tax that funds supplementary services, including private security. BIDs constitute a controversial form of urban revitalization to some because they privatize economic development and public safety efforts in public space. This study examines whether BIDs provide tangible benefits beyond their immediate boundaries to local residents in the form of reduced violence among adolescents. The empirical analysis advances an existing literature dominated by evaluation studies by introducing a theoretically driven dataset with rich information on individual and neighborhood level variables. The analysis compares violent victimization among youths living in BID neighborhoods with those in similarly situated non‐BID neighborhoods. We find no effect of BIDs on violence. However, we do find that youth violence is strongly correlated with neighborhood collective efficacy and family‐related attributes of social control. In conclusion, we argue that BIDs may be an agent of crime reduction, but this benefit is likely concentrated only in their immediate boundaries and does not extend to youths living in surrounding neighborhoods.