Statement of Purpose Sobriety checkpoints are a form of proactive policing in which law enforcement officers concentrate at a point on the roadway to systematically perform sobriety tests for all passing drivers. The intervention is highly effective for reducing alcohol-impaired driving and alcohol-involved crashes. Guided by general deterrence theory, we investigated whether sobriety checkpoints also unintentionally reduce violence in surrounding areas.

Methods/Approach This longitudinal ecological analysis used publicly available data for checkpoints conducted by the Los Angeles Police Department (LAPD) between 2012 and 2017, geocoded to points in the City of Los Angeles. The outcome was the density of incident reports of assaults around the checkpoint location, calculated using a kernel density function. Comparison units were matched 1:2 to the sobriety checkpoint events, selected as the same point location temporally lagged by exactly ±168 hours (i.e., at the precise time one week before and one week after the checkpoint). Mixed effects linear regression models assessed associations for the time that the checkpoints were in operation and for 0–48 hours after operations ended.

Results LAPD conducted 627 sobriety checkpoints during 2012–2017. Assault incidence was lower at the location and time when sobriety checkpoints were in operation compared to the same location ±7 days [b= -0.0108, 95% CI: (-0.0203, -0.0012)]. Associations remained for 0–6 hours after checkpoint operations ended [b= -0.010, 95% CI: (-0.019, 0.000)] but were not detectable 7+ hours after checkpoint operations ended [e.g., 7–12 hours: b= 0.0017, 95% CI: (-0.0076, 0.0110)].

Conclusion Sobriety checkpoints were associated with a decreased incidence of police-reported assaults during and for 6 hours after sobriety checkpoints were operational.

Significance This unintended benefit could potentially reduce the physical and mental burden of assaults. Research identifying the impacts of law enforcement on public health is critical for decreasing crime and violence and improving police-community relations.