Motor vehicle crash fatalities in the second year of 65 mph speed limits

Baum, Herbert M. / Wells, JoAnn K. / Lund, Adrian K.
Journal of Safety Research
Spring 1990

In 1987, the federal government relaxed the 55 mph (88 km/h) national maximum speed limit, permitting states to post 65 mph (104 km/h) speed limits on rural interstate highways. By the end of 1987, 38 states had done so; and two additional states followed suit in 1988. It is estimated that the higher speed limit caused motor vehicle crash fatalities to be 26% higher in 1988 than they would have been if the speed limit had remained at 55 mph. This translates into over 500 deaths attributable to the higher speed limits on rural interstate highways. Overall, it is estimated that more than 700 people, who would have lived had the limit not been raised, have died on rural interstate highways since states began to post 65 mph limits in 1987. The effect of the higher limit doubled between 1987 and 1988, and the 65 mph limit may cost far more in death and injury than predicted prior to the speed limit increase.