Iowa Attorney General Tom Miller submitted an amicus brief with the U.S. Supreme Court supporting the biofuels industry’s challenge of three federal small-refinery exemptions that could set a precedent for future exemption requests.The court case, HollyFrontier Cheyenne Refining v. Renewable Fuels Association, will determine whether the U.S. Environmental Protection Agency has the authority to enact small-refinery waivers, which allow oil companies to avoid blending ethanol into its fuel.Monte Shaw, Iowa Renewable Fuels Association executive director, at a Wednesday news conference described the waivers as a “get out of jail free card” for refineries.The 10th Circuit Court ruled the EPA waivers were illegal.Led by Miller and Nebraska Attorney General Doug Peterson, attorneys general from Illinois, Minnesota, South Dakota, Michigan, Oregon and Virginia joined the “friend of the court” brief.The brief calls the biofuel and agricultural industries a “cornerstone” of the economies of the involved states.These industries — and the rural economies that they anchor — have grown over the past 16 years in reliance on the promise of the Renewable Fuel Standard, or RFS, the brief said.