A U.S. appeals court on Thursday threw out planned federal fuel economy standards for many sport utility vehicles, minivans and pickup trucks, ruling that President George W. Bush’s administration failed to address why those so-called “light trucks” are allowed to pollute more than cars.

The 9th U.S. Circuit Court of Appeals also ruled that the standards, which were to go into effect next year, did not properly assess the risk to the environment and failed to include heavier trucks.