Automakers' Lobby Backs Trump Fuel-Economy Rollback Against 21-State Court Challenge

The main US automaker trade group has taken the federal government's side in the court fight over fuel-economy rules. Automotive World reports that the Alliance for Automotive Innovation filed its support for the reduced standards with the US Court of Appeals for the First Circuit.

The rule

The rule is the National Highway Traffic Safety Administration's (NHTSA) «Safer Affordable Fuel-Efficient Vehicles Rule III for Model Years 2022 to 2031», known as SAFE III. It was published in the Federal Register on Sept. 30, 2026, according to the states' petition. Automotive World says it sets a fleet-wide average of 34.9 mpg by 2031, down from the 50.4 mpg target set under President Biden in 2024.

Who is suing

The petition for review, dated Oct. 2, was filed by 21 states: California, Arizona, Colorado, Connecticut, Delaware, Hawaii, Illinois, Maine, Maryland, Massachusetts, Michigan, Minnesota, New Jersey, New Mexico, New York, North Carolina, Oregon, Rhode Island, Vermont, Washington and Wisconsin. The District of Columbia and the cities of Chicago, Denver, Los Angeles, New York and San Francisco joined them. The petition says the case is related to an earlier challenge to NHTSA's 2025 «Resetting the Corporate Average Fuel Economy Program» rule, which was paused until SAFE III was final.

The arguments

• Automakers: «Automakers require certainty and stability in the standards», the Alliance said in its filing, according to Automotive World. It warned that setting the rule aside would endanger capital planning, product development and validation «for hundreds of new vehicle models intended for the US market».
• States: Automotive World reports the states argue the government ignored the millions of EVs already on US roads, producing «a flawed, dramatically distorted analysis» of the maximum feasible fuel-economy level.
• The cost numbers: Automotive World notes that the Transportation Department's own figures show the rule cuts average compliance costs by $1,289 per vehicle but adds more than $1,600 in lifetime fuel spending.