Automated Red Light Camera Enforcement

A red light camera is a form of automated enforcement of traffic safety laws. Red light cameras photograph a vehicle’s license plate if the driver fails to stop at a red light, and the vehicle owner or driver is sent a ticket.1 Red light cameras should be used to aid traditional enforcement efforts or in locations where traffic stops are impractical or unsafe.1

Effectiveness and Use of Automated Red Light Camera Enforcement

The relationship between disregard of traffic signals and the risk of a crash and/or fatality is well established.1 In 2018, crashes involving red light running killed 846 people in the United States.2

Red light cameras are intended to enforce compliance with traffic signals and have been found to reduce red light running violations.3-5 The effects of four red light cameras were examined one year after installation in 2010 in a county in Virginia. Relative to what was expected without cameras, the odds of violations occurring at least 1.5 seconds after the light turned red in those intersections were lower compared to the warning period before ticketing began.5

A Cochrane review of studies through 2002 concluded that red light cameras reduced total casualty crashes but was not able to conclude whether the cameras reduced specific crash types.6 Updating and expanding upon this review, a Campbell Collaboration review of studies through 2016 found that red light cameras reduced total injury crashes; the review was also able to examine two specific crash types―right angle crashes and rear end crashes.7 Rear end crashes are lower impact, while right angle crashes are more dangerous.1 For right angle crashes, the review found a decrease in overall crashes and a decrease in injury crashes. For rear end crashes, the review found an increase in overall crashes but no significant difference in injury crashes.7 More recent studies have found similar results.8-10

Best practice is to place signs indicating the presence of automated red light enforcement systems.1,11 The signs provide fair warning of potential enforcement and allow drivers to comply with the traffic signal system before a crash or enforcement event occurs.1,11

Recent or Current Legislation by State

You can visit the automated enforcement laws by stateexternal icon web page on the Insurance Institute for Highway Safety’s website for up-to-date information on automated red light camera enforcement by state.12,13

Costs of Automated Red Light Camera Enforcement and Time to Implement

Camera equipment may be purchased, leased, or operated by a vendor.1 Most jurisdictions work with vendors to install cameras, process images, and issue citations.1 Costs of implementation depend on equipment type, program characteristics, and vendor negotiations.1 Program costs are usually covered by fines collected from citations, and vendor payments are made either on a set monthly basis or based on the number of citations.1

It generally requires up to nine months for full automated red light camera enforcement implementation after any relevant legislation has been enacted.1

Other Issues and Resources

In a report for the Governors Highway Safety Association, equitably implemented and transparent automated enforcement was recommended as a strategy to advance racial equity in traffic enforcement.14

You can read Chapter 3, Section 2.1 of NHTSA’s Countermeasures that Work: A Highway Safety Countermeasure Guide for State Highway Safety Officespdf iconexternal icon (Tenth Edition, 2020) to learn more about the topics above or other issues related to red light camera enforcement, such as variation in state laws, level of public acceptance, and lessons learned.1

You can read the RAND Corporation’s final reports for MV PICCS 1.0/2.0external icon and MV PICCS 3.0external icon for more information about how effectiveness and costs were incorporated into the MV PICCS tool for this intervention.


The first red light cameras in the United States were installed in the early 1990s in New York City.12,15 The number of U.S. communities using automated red light camera enforcement peaked at 533 in 2012.16 Community opposition to cameras and trouble funding camera programs have been listed as reasons for programs being discontinued.16

As of January 2022, 338 communities in 22 states and the District of Columbia use automated red light camera enforcement.16 States and jurisdictions vary in how red light camera violations are treated, with some treating them as civil offenses and some treating them as moving violations.12 See above for current legislation.


  1. Venkatraman, V., Richard, C. M., Magee, K., & Johnson, K. (2021). Countermeasures that work: A highway safety countermeasures guide for State Highway Safety Offices. (Report No. DOT HS 813 097). Washington, DC: National Highway Traffic Safety Administration iconexternal icon
  2. Federal Highway Administration. (2022). About intersection safety. icon. Accessed on 2/7/2022.
  3. Retting, R. A., Williams, A. F., Farmer, C. M., & Feldman, A. F. (1999). Evaluation of red light camera enforcement in Fairfax, Va., USA. ITE Journal. icon
  4. Retting, R. A., Williams, A. F., Farmer, C. M., & Feldman, A. F. (1999). Evaluation of red light camera enforcement in Oxnard, California. Accident Analysis & Prevention, 31(3), 169–174. icon
  5. McCartt, A. T., & Hu, W. (2014). Effects of red light camera enforcement on red light violations in Arlington County, Virginia. Journal of Safety Research, 48, 57–62. icon
  6. Aeron-Thomas, A. S., & Hess, S. (2005). Red-light cameras for the prevention of road traffic crashes. Cochrane Database Syst Rev, (2), Cd003862. icon
  7. Cohn, E. G., Kakar, S., Perkins, C., Steinbach, R., & Edwards, P. (2020). Red light camera interventions for reducing traffic violations and traffic crashes: A systematic review. Campbell Systematic Reviews, 16(2), e1091. icon
  8. Mahmassani, H. S., Schofer, J. L., Johnson, B. L., Verbas, O., Elfar, A., Mittal, A., & Ostojic, M. (2017). Chicago red light camera enforcement: Best practices and program road map. Evanston, IL: Northwestern University, The Transportation Center iconexternal icon
  9. Ko, M., Geedipally, S. R., Walden, T. D., & Wunderlich, R. C. (2017). Effects of red light running camera systems installation and then deactivation on intersection safety. Journal of Safety Research, 62, 117–126. icon
  10. Hu, W., & Cicchino, J. B. (2017). Effects of turning on and off red light cameras on fatal crashes in large U.S. Cities. Journal of Safety Research, 61, 141–148. icon
  11. Washington, S., & Shin, K. (2005). The impact of red light cameras (automated enforcement) on safety in Arizona. (FHWA-AZ-05-550). Phoenix, Arizona: Arizona Department of Transportation icon
  12. Insurance Institute for Highway Safety, & Highway Loss Data Institute. (2021). Red light running. icon. Accessed on 1/27/2022.
  13. Insurance Institute for Highway Safety, & Highway Loss Data Institute. (2022). Automated enforcement laws. icon. Accessed on 1/27/2022.
  14. Kimley-Horn, & Governors Highway Safety Association. (2021). Equity in highway safety enforcement and engagement programspdf iconexternal icon. Governors Highway Safety Association.
  15. New York City Department of Transportation. (2009). New York city red light camera program: Program review 1994–2008. New York, NY: Author iconexternal icon
  16. Insurance Institute for Highway Safety, & Highway Loss Data Institute. (2022). U.S. Communities using red light cameras. icon. Accessed on 1/27/2022.