Program overview

  • Providing automated enforcement: A speed camera is an automated approach to enforcing traffic safety laws along a road segment. When a driver is exceeding the speed limit, a speed camera photographs or records video of the vehicle. With the vehicle’s license plate captured, local law enforcement can send the vehicle’s owner or the driver a speeding ticket. Ultimately, speed cameras may reduce traffic speeds and the incidence of traffic collisions.

  • Targeted toward high-risk areas: Speed cameras are often deployed along high-crash corridors or along roads adjacent to special uses, like schools or construction sites. They may be used in conjunction with traditional law enforcement efforts or in locations where enforcement may be unsafe or impractical (e.g., highways).

  • Differing approaches to enforcement: Jurisdictions differ in how they attribute responsibility for speeding violations. In some cases, the registered owner of the vehicle is liable, regardless of whether they were the driver at the time of the violation. In other cases, however, the driver is targeted for enforcement. The latter approach requires a more intensive review process to accurately identify the driver. Often, the approach to enforcement is dictated by state law.

  • Varied state laws: The ability of local governments to deploy speed cameras varies by state. In some states, the use of automated enforcement systems is prohibited. In others, enabling legislation sets out specific restrictions for their use. In the majority of states, however, there is no specific legislation addressing automated speed cameras.

Cost per Participant
Not available

Multiple studies with rigorous designs demonstrate that automated speed enforcement cameras are a well-supported strategy for reducing traffic speeds and traffic-related injuries and fatalities.

  • Mix covert and overt enforcement: Fixed speed cameras may produce rapid reductions in speeds and traffic collisions along the road segment where they are deployed. However, drivers may adapt their driving behavior by taking an alternative route or by speeding before entering or after leaving the enforcement zone. In contrast, mobile speed cameras may produce a more generalized reduction in speeding and traffic collisions, as it is difficult for drivers to anticipate their location. To achieve rapid results along high-priority corridors as well as a more generalized improvement in traffic safety, local governments may consider implementing both fixed and mobile speed cameras.

  • Publicize automated enforcement: Automated enforcement measures only reduce traffic speeds if drivers are aware of them. As such, fixed speed cameras should be well-signed, and mobile or covert speed cameras should well publicized (e.g., in local news, or by issuing warnings for first offenses). Additionally, providing the general public with information about the speed cameras prior to and during their implementation may increase the perception that automated enforcement is “fair,” ultimately increasing public support for the intervention.

  • Use lower enforcement thresholds: When the threshold at which an enforcement action occurs is significantly higher than the speed limit (e.g., greater than 10 mph), drivers may be encouraged to continue driving over the speed limit. As such, local governments should adopt enforcement thresholds that are only somewhat higher (e.g., less than 5 mph) than the posted speed limit.