Effects of Law Enforcement Presence, Frequency, and Duration on Speeding

Speeding, exceeding the posted speed limits, or traveling too fast for conditions was a contributing factor in almost 29 percent of all fatalities in 2021. Of the 42,939 fatalities that occurred on our Nation’s roadways that year, 12,330 were speeding-related—an increase of 7.9 percent from 2020 (Stewart 2023). Studies clearly show that higher speeds result in greater impact at the time of a crash, which leads to more severe injuries and fatalities (Elvik 2005; WHO 2008). Speed management is essential to reduce injury risk for all road users in any crash, especially for vulnerable road users (VRUs) such as pedestrians and bicyclists. As one of five key elements of a safe transportation approach to reduce death and serious injuries, safe speed on our roadways is essential. To achieve a safe transportation system, road safety practitioners

should not only manage speeds but make achieving safe speeds on all roads a cornerstone of their safety policies. Besides implementations of education and engineering strategies and associated countermeasures, law enforcement of posted speed limits at roadway segments with speeding issues is important for speed management. When safe speed cameras cannot be installed at those critical locations, frequent presence of law enforcement becomes crucial. Since law enforcement officers cannot be at the locations with speeding problems all the time, it is needed and beneficial to study and provide law enforcement and transportation agencies with recommendations on frequency and duration of law enforcement presence to achieve effective speed management.

This study sponsored by Florida Department of Transportation (FDOT) District 7 evaluated the effects of law enforcement activities on speeding. The project team used the citations and warning data collected through the FDOT District 7 Enhanced Law Enforcement Engagement (ELEE) project to assess the effects of law enforcement presence, frequency, and duration on vehicle speeds on study corridors. The ELEE data includes the date, time frame of enforcement, state road, and nearest intersection or mile marker, as well as the speeding related citations and warning issued during each activity. The project team obtained the speed information during study periods covering all study roadway segments from the Regional Integrated Transportation Information System (RITIS). The warming and citation information was then linked to the speed data along with other roadway information to enable the creation of the speed profiles, and to estimate the effects of warnings and citations on speeding using basic summary statistics and statistical analysis.

The research findings demonstrate the effectiveness of law enforcement in mitigating speeding problems and the effects of law enforcement activities last on speed management. The study illustrates how long the effects of law enforcement activities last. In other words, it highlights the duration of time drivers reduce their speed after law enforcement activities. The study is unique, and the results provide valuable insights into how often law enforcement officers should be present at locations or roadway segments with speeding issues.