Assessing the Role of Context in Traffic Light Violations

In France the struggle against red light running behaviour is a government priority for reducing road accidents and fatalities. The objective of this study is to measure the frequency of red light runnings and assess the factors impacting these behaviours. Pneumatic counters were used to measure running behaviours during several weeks in 2009 on 26 traffic lights in Nantes. A hierarchical Poisson model was run on the collected data to estimate the “individual demands for red light running” before the deployment of automated enforcement devices. Red light runnings are more numerous during rush hours, but the propensity to violate red lights is most marked at night. In addition to time periods and traffic conditions, traffic light violations vary significantly from one site to another, suggesting that environment influences the propensity to abide by traffic lights. These empirical results are discussed from a public policy perspective.