Commentary

Road pricing with privacy protection

Comprehensive road pricing requires charging users based on the amount of roadway they use. Conceptually, this implies a mileage-based charge for road users. Economists have long favored this approach as the most efficient approach to managing our roads (and, incidently, privatizing them). One of the more important objections to this approach, however, revolves around the potential for the technology used to measure mileage of travelers to enable “big brother.” If the government can calculate your mileage and send you the bill, it must know where you are. This is an important and legitimate concern, but, as Randal O’Toole points out on his blog “The Antiplanner,” it can be addressed relatively easily.

a new paper by the Antiplanner’s faithful ally Gabriel Roth and an engineer named Bern Grush propose an intermediate model that uses the kind of system made for anonymous cell phones. In this model, the GPS transponders send basic data to proxy servers that calculate the user fees and pass that information to a payment operator that matches the billing to either a prepaid account (assuring total privacy) or a credit card (which could let authorities know how much people have spent on tolls but not where or when they spent it). This system would reduce the up-front cost of the GPS transponder and eliminate the need for a subscription service.

At least three companies currently have technologies that allow privatcy to be protected in this way: Skymeter, Transcore, and Siemens.