Abstract: | Policies to reduce carbon emissions by vehicles, such as fuel economy standards and gasoline taxes, have impacts on vehicle weight and thus on safety. This paper develops a model that separately identifies the impact of vehicle weight on mortality and selection effects that impact accident propensity. The main results are that (1) the safety externalities associated with heavy vehicles are greater than the environmental ones; (2) under fuel economy standards, vehicle weights have recently decreased with little likely effect on accident deaths; and (3) similar environmental benefits could be combined with substantial reductions in deaths by implementing higher gasoline taxes. (JEL H23, D62) |