Editorial: Per-mile tax not so bad, with changes

Say you bought a fuel-efficient car, cut your gasoline consumption and are reaping the benefits - including paying less in gas taxes. A proposal to change how drivers are taxed might seem like a smackdown, at first. Under a new plan, drivers would be taxed on how many miles they travel and not necessarily on how many gallons of gas they buy.

Those taxes pay to fix roads, and gas tax revenues aren't keeping up. In fact, they're going down. Viewed in that light - and with some caveats - Illinois Senate President John Cullerton's proposal makes some sense.

The alternative, experts say, is a 30 cents-per-gallon increase in the gas tax and a 50 percent hike in registration fees to raise $43 billion over the next 10 years to cover maintenance of the state's roads and bridges.

Cullerton's plan is based on an idea that's been around for years in transportation circles. Oregon has expanded on pilot programs launched in 2012 to charge taxes by the mile. California is moving ahead with a pilot of its own. Aside from drawing a more direct link between driving and road wear and tear, it has the potential to someday allow for variable fees for driving in congested city centers, during peak times, in special lanes, or in other premium conditions.

Doing all that would require measuring where people drive, a sticking point in many proposals. Some people don't want anyone to know that information. Others, like those using traffic apps on their phones, already are sharing their driving habits.

Cullerton's plan would let people avoid being monitored and pay a flat $450 a year, or 1½ cents per mile on an estimate of 30,000 miles traveled. Or, drivers could choose a device to monitor the odometer and pay taxes on mileage. Or, they could choose a smarter device that wouldn't charge for out-of-state or tollway driving.

We like the options. Still, identifying who has access to data needs to be set down in law and shared with consumers.

Cullerton says Illinois drivers would still pay gas taxes at a pump and get a refund from the state, enabling a system for taxing interstate truckers and out-of-state drivers. Some additional ideas also deserve consideration. Under his proposal, Cullerton expects owners of gas-guzzling cars would pay less than they do now, while owners of energy-efficient cars would pay more. But there should be a reward for people who conserve resources. One option would be to vary the tax based on vehicle weight, since heavier vehicles use more gas and can have a much greater cost in terms of road wear and tear.

One advantage of the gas tax is the reward for being green. It wouldn't be hard to build a similar perk into road tax legislation.