[August]

Originally Posted by Growler

August, some states don't perform annual inspections, but that doesn't really matter, either.

In Maryland, all drivers on vehicles not otherwise waived (historic, or above a certain age, mostly) participate in the Vehicle Emissions Inspection Program (VEIP) every other year, meaning two years between tests. Mileage is recorded at that time. For taxation purposes, it would not be a great stretch to take the last two VEIP mileage readings, average them, and bill half annually as tax.

That's what I figured. It'd be a far less irritating way of bringing this about than forcing people to purchase special tracking equipment for their vehicles.