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Two Decades of Photo Enforcement in the United States: A Brief Summary of Experience and Lessons Learned

The use of cameras for red light and speed enforcement has grown substantially since the first implementation in 1987. This article summarizes this growth, highlighting evaluations of the effectiveness of photo enforcement, effect on crash trends, public opinion and major legal challenges concerning its use. Studies evaluating the effectiveness of red light cameras suggest that they are effective in reducing red light violations and injury crashes. Automated speed enforcement have been shown to substantially reduce speed violations and may reduce crashes. Despite substantial evidence of effectiveness and relatively high public support, photo enforcement remains controversial. Some legal challenges have produced judicial findings that negatively affect photo enforcement programs, while other findings have affirmed its legality. In order to help ensure the success of photo enforcement programs, it is recommended that agencies focus on safety benefits, emphasize fairness in program design and operations, avoid the appearance of a revenue motive, anticipate legal setbacks, pay attention to proper engineering, use effective communication strategies, and evaluate program performance and outcomes.