Higher gasoline taxes can be justified because cars cause significant local, regional, and global air pollution damages. This study examines whether charging higher taxes would result in significant emission reductions. Both experimental survey data and actual behavior in Southern California and Connecticut are evaluated to explore whether people would change their driving behavior in response to higher gasoline prices. Both sets of results reveal that drivers are price inelastic in the short run (-0.4 to -0.6) and long run (-0.5 to -0.7). Imposing environmental surcharges on gasoline will result in only a small reduction in driving and thus only a small improvement in the environment. Such taxes will place a heavy and clear burden on drivers, however, making gasoline taxes extremely unpopular. Finally, the study finds that the income elasticity of gasoline is low (0.1-0.2) so that the gas tax will fall heavily on the poor.