“In the past, the efficiency costs of implementing a system of VMT charges — particularly the costs of users’ time for slowing and queuing at tollbooths — would clearly have outweighed the potential benefits from more efficient use of highway capacity,” CBO wrote. “Now, electronic metering and billing are making per-mile charges a practical option.”…

“Any given driver’s highway use also imposes costs on other users, on nearby nonusers, on the environment, and on the economy in the form of congestion, risk of accidents, noise, emissions of greenhouse gases and pollutants that affect local air quality, and dependence on foreign oil,” CBO said.

On how to implement the idea, CBO said it is unclear how much it would cost to “install metering equipment in all of the nation’s cars and trucks.”