Can the police cool down quality-of-life hotspots? A double-blind national randomized control trial of policing low-harm hotspots

Substantial evidence suggests that focussing police resources on hotspots of crime has a discernable crime-reduction effect. However, little is known about the efficacy of proactively policing areas with higher concentrations of more common low-harm problems in society. This study evaluates the first national double-blind randomized controlled trial in which clearly identifiable hotspots (n = 488) of low-harm 'quality-of-life' incidents nested in 31 participating police stations were randomized to be either actively policed by any available police officer or by 'business-as-usual' reactive policing over a 12-month period. A series of count-based regression models show a moderate and statistically significant reduction in the number of quality-of-life incidents in treatment versus control hotspots, with more than 2,000 quality-of-life incidents prevented, without evidence of spatial displacement to street segments nearby. However, we find no diffusion of benefits in terms of other crime types within the same hotspots, which may suggest that either low- and high-harm crime hotspots are not spatially aligned with each other, that focussing police officers on one type of crime does not produce a suppression effect on other types of crime, or both. We discuss the implications of these results for crime policy and future research.