Effectiveness of red light running camera enforcement program in reducing crashes: evaluation using "before the...

The focus of this manuscript is to evaluate and assess the effectiveness of red light running camera (RLC) enforcement program in reducing crashes at signalized intersections. Data from January 1997 to December 2010 for thirty-two signalized intersections in the city of Charlotte, North Carolina, where RLCs were installed between August 1998 and August 2000 and terminated in fall 2006, were gathered, analyzed, and compared for "before the installation", "after the installation", and "after the termination" periods. Descriptive analysis and paired t-tests were performed using rear-end, sideswipe, left-turn, angle, and right-turn crashes as well as the number of total crashes. The expected number of total crashes, had RLC enforcement program not been implemented, was computed using the empirical bayes (EB) method and compared to the actual number of total crashes for "after the installation" and "after the termination" periods. Results obtained indicate that RLC enforcement program leads to an increase in sideswipe and rear-end crashes at ≥ 50% of the signalized intersections. It is effective in reducing total crashes at 50% and 16% of the thirty-two signalized intersections when analyzed considering "before the installation - after the installation" and "before the installation - after the termination" scenarios, respectively. Benefits due to reduction in the number of total crashes may be higher if RLC enforcement program is implemented at signalized intersections with (1) total entering vehicles per day less than 40,000, (2) fewer than 20 rear-end crashes per year, or (3) fewer than 5 sideswipe crashes per year.