The U.S. Supreme Court has refused to hear a dispute about how the state of Oregon taxes heavy trucks.

That means the Oregon law will stand. It allows intrastate haulers to pay a flat tax fee – while interstate haulers pay based on weight and distance.

The American Trucking Association had challenged the law in court arguing that it discriminates against interstate truckers by giving breaks to local haulers of wood, sand and gravel.

But the Oregon Supreme Court ruled there was no evidence of unfairness.