Ezra links to a story in which Ray LaHood says that the government is considering taxing VMT, as a means to fund transportation projects. From a strict policy perspective, it’s a pretty good idea (depending on the cost of deployment of the GPS systems). Folks who drive more are responsible for more wear and tear on the roads, but more importantly, they’re responsible for more of the negative social costs of driving — pollution, carbon emissions, congestion, and accidents. And where a gas tax may not reduce driving (it might simply lead to increased efficiency), a VMT tax absolutely will.
But I don’t know what I think about this, politically speaking. As Ezra notes, the immediate thing that comes to mind is the creepiness factor; the government will know where you’ve been driving. I don’t know if that’s enough to derail a VMT tax, but I know that the GOP will shamelessly hammer away at the theme, despite having officially become the part of civil liberties infringements.
The bigger issue, I think, is that the tax is anti-driving, obviously and on its face. This doesn’t bother me, but it will bother lots of other folks. A gas tax can be sold as a means to reduce pollutants and carbon emissions (or for the national security set, oil imports). But it’s not necessarily an attempt to reduce driving, and drivers can reduce its impact while still extreme commuting by buying a smaller car. A congestion toll is there to reduce congestion. Sure, it reduces driving, but the point, from a driver’s perspective, is that paying the toll generates a congestion free commute.
A VMT tax, by contrast, is payment for the very right to drive (and in America, this is perceived as a right). As such, I’m not sure it would fly. I could be wrong, of course. But my preferred method of financing transportation improvements remains an increase in the gas tax, combined with a broad and significant move toward congestion pricing.