CRASH REDUCTIONS ASSOCIATED WITH RED LIGHT CAMERA ENHFORCEMENT IN OXNARD, CALIFORNIA

Red light cameras are increasingly being used in communities to deter drivers from running red lights. Numerous studies have established that red light camera enforcement sharply reduces red light violations, but little information is available regarding crash effects. The purpose of this study was to estimate the impact of red light camera enforcement on crashes in one of the first U.S. communities to employ such cameras - Oxnard, California. Crash data from the California Statewide Integrated Traffic Records System were analyzed for Oxnard and for three comparison cities that did not implement red light camera enforcement for a period of 29 months before and after implementation of the program in Oxnard. Changes in crash frequencies after enforcement were compared for Oxnard and control cities, and for signalized and nonsignalized intersections, using a generalized linear regression model. Overall, crashes at signalized intersections throughout Oxnard were reduced by 7% and injury crashes were reduced by 29% as a result of red light camera enforcement. Although the crash data did not contain sufficient detail to identify crashes that were specifically red light running events, right-angle collisions - the type of crash most associated with red light violations - were reduced by 32%, and right-angle crashes involving injuries were reduced by 68%. There was no significant effect on rear-end crashes. Because red light cameras can be a permanent component of the transportation infrastructure, crash reductions attributed to camera enforcement should be sustainable.