Citation

Schrock SD, Udaipurwala MT, Fitzsimmons EJ. Transp. Res. Rec. 2016; 2584: 1-7.

Copyright

(Copyright © 2016, Transportation Research Board, National Research Council, National Academy of Sciences USA, Publisher SAGE Publishing)

DOI

10.3141/2584-01

PMID

unavailable

Abstract

Red light running (RLR) is an event where a vehicle enters an intersection when the red signal is indicated. These events are known to cause hundreds of fatalities, thousands of injuries, and tens of thousands of property damage crashes annually. The objective of this research study was to evaluate the changes in RLR events at freeway on-ramp intersections in the presence of targeted enforcement stationed on the adjacent on-ramp. The enforcement officers were aided by confirmation lights that could only be seen by the officers stationed on the on-ramps. The primary performance metric used was the change in RLR rates between the before period and 1 month and 3 months after installation. It was found that the treatment sites experienced statistically significant reductions of 60% and 56% in violation rates during the respective study periods. The control sites also experienced 39% and 60% reductions in violation rates during the respective study periods. Additional analysis of the number of officers deployed and citations written was conducted to determine a possible reason for the reduction in violation rates at the control sites, but the results indicated no change in the enforcement structure between the before-and-after periods. It is possible that the effects at the study sites changed driver behavior over a wider area, which may have unexpectedly been observed at the control sites. This study showed that confirmation lights, when used in combination with targeted enforcement, can have a beneficial impact in reducing RLR violations at on-ramp signalized intersections, possibly over a wider area than expected.