This paper presents a theoretical and empirical analysis of the effects of no fault automobile insurance on fatal accident rates. As a mechanism for compensating the victims of automobile accidents, no fault has several important advantages over the tort system. However, by restricting access to tort, no fault may weaken incentives for careful driving, leading to higher accident rates. We conduct an empirical analysis of automobile accident fatality rates in all U.S. states over the period 1968-1994, controlling for the potential endogeneity of no fault laws. The results support the hypothesis that no fault is significantly associated with higher fatal accident rates than tort.