Traffic Safety Impacts of Reduced Police–motorist Interactions

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September 11th, 2026

The original scope of this work was intended to examine the relationship between changes in police traffic enforcement—particularly reductions in traffic stops—and roadway safety outcomes across multiple jurisdictions using a case-control design. Due to limitations in the availability of and trends in relevant data across sites, findings of the case studies presented in this report reflect only observed associations within specific contexts of available information rather than definitive causal effects. Results reported in this document are influenced by variations in data quality, external factors affecting driving behavior and enforcement practices, and other unmeasured confounding variables.

Traffic Safety Impacts of Reduced Police–motorist Interactions