DETROIT — The Trump administration on Friday launched an all-out assault on California over automotive mileage rules, telling state officials that only the federal government has the power to regulate greenhouse gas emissions and fuel economy.
The assault began with the Justice Department opening an antitrust investigation into a deal between California and four automakers for tougher pollution and related mileage requirements than those sought by President Donald Trump. Then, two federal agencies told the state it has no authority to regulate greenhouse gas emissions.
The outcome of the fight will make or break Trump’s effort to relax Obama-era mileage standards nationwide, weakening one of the past administration’s main efforts to slow climate change. California has congressionally granted authority to set its own, tougher emissions standards under the 1970 Clean Air Act.