NJ DOT report finds red-light cameras reduce crashes and citations; insufficient data for program conclusions
The third annual analysis of red-light safety cameras (photo enforcement) by the New Jersey Department of Transportation (NJDOT) has found overall decreases in crashes, as well as decreases in the number of annual citations issued, for all program years.
A traffic control signal monitoring system—i.e., a Red Light Running (RLR) system—is an integrated device utilizing one or more cameras and sensors that work in conjunction with a traffic control signal to produce images of vehicles that disregard a red signal. These images are transmitted to law enforcement officials who review both still photos and video produced by the system to determine if a violation has in fact occurred.
As of 31 December 2012, there were eighty-three (83) intersections in twenty-five (25) municipalities within eleven (11) counties in New Jersey authorized for program participation.
Based on the established reporting parameters, monitoring systems at two (2) RLR locations now have three years of data for study analysis. Additionally, 22 intersections have been active for two full years and another 23 intersections have been operating for one full year. The annual report analyzes the data generated within each distinct group, as well as provides a program-wide analysis of the data generated within each year of operation.
Among the findings were:
For the two locations with three years of data, when the Pre-Camera year crash data is compared to Year 3, right-angle crashes are down 86%, rear-end crashes are down 58%, total crashes are down 72%, and estimated crash severity costs have been reduced by $246,200.
Regarding the citations issued at these locations, comparing Month 1 (the first month) of operation with Month 36 (the last month at the end of the three year period), citations are down 83%. While there is no expectation that crashes or citations will drop to zero, there is an expectation that driver behavior will change with the presence of RLR, and these locations appear to be fulfilling these expectations.
For the 22 locations that have been active for two full years, when the Pre-Camera year data is compared to Year 2, right-angle crashes are down 60%, rear-end crashes are down 7%, total crashes are down 27%, and estimated crash severity costs have been reduced by $787,200.
Regarding the citations issued at these locations, comparing Month 1 of operation with Month 24, citations are down 61%. However, when compared with the data reported within the 2012 Annual Report, which showed increases in all categories except right-angle crashes, the Year 2 data emphasizes the importance of collecting a sufficient amount of data before drawing conclusions for programs such as this.
For the twenty-three (23) intersections that have been operating for one full year, when the Pre-Camera year is compared to Year 1, right-angle crashes are down 15%, rear-end crashes are down 3%, total crashes are down 5%, and estimated crash severity costs have decreased by $2,176,100.
Regarding the citations issued at these locations, comparing Month 1 with Month 12, citations are down 31%. These first-year statistics are markedly different from the 2012 Annual Report, suggesting that the driver-behavior learning curve may have become stronger with continued program operation.
The data show overall decreases in crashes, as well as decreases in the number of annual citations issued, for all program years. For the Group 1 signals, having three (3) full years of data, it appears reasonable to conclude that RLR is a viable safety tool at those locations and at locations having similar speed and volume characteristics. However, it is not prudent at this time to draw any final programmatic conclusions, as two (2) data points in a single city do not have a substantial bearing on RLR data collected within other statewide regions at locations with varying engineering attributes.
Additionally, while the safety trends recorded in Year 2 within Group 2 and in Year 1 within Group 3 indicate that driver behavior is being modified, less than three (3) data years is not adequate to develop conclusions, let alone recommendations.
Legislative background.A New Jersey law required the New Jersey Department of Transportation (Department) to establish a 5-year pilot program to determine the effectiveness of the installation and utilization of traffic control signal monitoring systems.
The pilot program officially began 16 December 2009, the date the first monitoring system was activated. Because the law establishing the pilot program authorizes the use of traffic control signal monitoring systems only during the five-year pilot program, this pilot program will end in December 2014.
After 16 December 2014, municipalities will lack statutory authority to continue the operation of traffic control signal monitoring systems, including the issuance of citations for red light violations.