If automakers don't want politicians butting into dealer-factory affairs, they should treat those relations as something other than a game of three-card monte.
Under pressure from dealers, automakers increasingly - if reluctantly - are agreeing to pay dealerships prevailing retail rates for parts used in warranty repairs. But they often have covered those higher rates by imposing surcharges on new-vehicle invoice prices.
Maine passed a law in 2003 that prohibits that kind of shell game. A federal appeals court upheld the law last fall, and the Supreme Court refused this spring to hear automakers' challenge to that ruling. Now dealers in other states will want similar statutes.
A better alternative: Car companies could reimburse their dealerships for warranty work with no strings attached.