Adoption of right turn on red: Effects on crashes at signalized intersections

By the end of the 1970's, all states in the U.S. had modified their laws to permit drivers to turn right on steady red at signalized intersections. Police-reported crash data from six states where permissive right turn on red (RTOR) laws were adopted during 1974–1977, as well as data from three states where the law in effect was unchanged throughout the period, were used to determine the effect of adopting such laws on the frequency of crashes involving right turning maneuvers at signalized intersections. The increase in the overall frequency of such crashes in states that adopted permissive right turn on red laws exceeded by more than 20% the comparable change in states that retained the same laws. Larger increases were found in urban areas (25%), and for pedestrian crashes (57%) especially in urban areas (79%). An increase of over 30% was found for child pedestrians, 100% for adults, and 110% for elderly pedestrians after adoption of RTOR.