Risk reduction or risk compensation? The case of mandatory safety-belt use laws

Abstract

The technological approach to risk regulation seeks to lessen the incidence of mortality and morbidity by modifying environmental conditions. Insofar as risk-taking behavior is purposive, social scientists have predicted that technological progress may be negated by various forms of "risk compensation." The validity of this hypothesis is tested in the transportation sector with data from the U.S. on the effects of new mandatory safety-belt-use laws. A fixed-effects model of traffic fatality counts is estimated using pooled data from 50 states during the 1975–1987 period. Results suggest that such laws have reduced mortality among car occupants to a degree that is compatible with the predictions of technologists. However, there is weak evidence of increased mortality among some nonoccupants, a pattern predicted by risk-compensation theorists. The lifesaving effects of belt-use laws are largest in states that permit primary police enforcement and appear to be somewhat larger for front-seat occupants age 21 and under. Although offsetting behavior appears to be small relative to lifesaving effects, it may take several more years for any compensatory behavior to achieve a new equilibrium.