The tax on fuel represents another user tax. Fuel consumption is a crude measure of road costs caused by a vehicle because of variations in fuel efficiency, size, and weight. Nonetheless, a fuel tax does relate to highway usage. The motor vehicle sales and use tax, vehicle license taxes, and drivers permits are also user taxes. They charge highway users as a class, but because they are lump sum payments unrelated to highway usage, they do a poor job of measuring specific road costs caused by individual users.
Tolls are the most flexible device for charging highway users.
They can be adjusted for distance traveled, type of vehicle, and congestion. Virginia made a major shift away from highway user charges in 1986 when a one-half percent increase in the general sales and use tax was earmarked for transportation. The principal user taxes in Virginia the fuels tax, registration fees, vehicle and driver licenses, and the motor vehicle sales tax have not changed since 1986. In recent years tax revenue from motor vehicles sales tax has grown rapidly in response to record vehicle sales and a larger proportion of expensive vehicles. The other transportation fund sources, which are based on units rather than dollar amounts, have grown only modestly.