Hot spots policing and crime prevention: A systematic review of randomized controlled trials

Crime scholars and practitioners have argued that police actions should be focused on high-risk crime places rather than spread thinly across the urban landscape. This review examines five randomized controlled trials of the effects of concentrating police enforcement efforts on crime hot spots. The findings of these evaluations suggest that focused police actions can prevent crime and disorder in crime hot spots. A meta-analysis of the effect sizes from the five experiments reveals a statistically significant mean effect size for hot spots policing interventions; this suggests overall reductions in citizen calls for service in the treatment hot spots relative to the control hot spots. These studies also suggest that focused police actions at specific locations do not necessarily result in crime displacement. Although these evaluations reveal that these programs work in preventing crime, additional research is needed to unravel other important policy-relevant issues such as community reaction to focused police enforcement efforts.     

International sex offender registration laws: research and evaluation issues based on a review of current scientific literature

In many jurisdictions, anyone convicted of a sexual offense is required to register with police, often for life. Nine different countries have now implemented sex offender registries in an attempt to protect the public from the perceived threat posed by sexual offenders. Yet such laws have been criticized as being overly inclusive, tying up limited law enforcement resources to track many offenders who pose little risk of sexual reoffending. This paper considers the available research evidence relevant to the effectiveness of such laws for the deterrence of sexual offending and the investigation of sex crimes. It is concluded that significant gaps persist in our knowledge of whether existing laws effectively reduce sexual offending or reoffending and that large-scale, well-designed studies of the impact of sex offender registration on rates of offending, the collateral consequences to offenders and their families, and the costs of such laws are needed.