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Tuesday, November 10, 2026Nov 10

Trump challenges California power to control auto pollution

FILE - In this Thursday, April 18, 2019, file photo, a sign for the Department of Justice hangs in the press briefing room at the Justice Department, in Washington. The U.S. Justice Department is conducting an antitrust investigation of four automakers that have signed on with California in a deal to toughen tailpipe emissions standards. In July, Ford, Honda, Volkswagen and BMW reached a deal with California to abide by standards that are tougher than those preferred by the Trump administration. The standards are closely linked with fuel economy requirements.    (AP Photo/Patrick Semansky, File)
FILE - In this Thursday, April 18, 2019, file photo, a sign for the Department of Justice hangs in the press briefing room at the Justice Department, in Washington. The U.S. Justice Department is conducting an antitrust investigation of four automakers that have signed on with California in a deal to toughen tailpipe emissions standards. In July, Ford, Honda, Volkswagen and BMW reached a deal with California to abide by standards that are tougher than those preferred by the Trump administration. The standards are closely linked with fuel economy requirements. (AP Photo/Patrick Semansky, File) FILE - In this Thursday, April 18, 2019, file photo, a sign for the Department of Justice hangs in the press briefing room at the Justice Department, in Washington. The U.S. Justice Department is conducting an antitrust investigation of four automakers that have signed on with California in a deal to toughen tailpipe emissions standards. In July, Ford, Honda, Volkswagen and BMW reached a deal with California to abide by standards that are tougher than those preferred by the Trump administration. The standards are closely linked with fuel economy requirements. (AP Photo/Patrick Semansky, File)

The Trump administration on Friday launched an all-out assault on California over mileage rules, opening an antitrust investigation and telling state officials that they appear to be violating federal law in a deal with four automakers setting tougher automotive emission standards.

The outcome of the emissions fight will make or break an effort by President Donald Trump to relax Obama-era mileage standards nationwide. California’s congressionally granted authority to set its own, tougher emissions standards under the 1970 Clean Air Act has long prodded automakers to adopt more fuel-efficient passenger vehicles.

Ford and Honda confirmed receiving a letter from the U.S. Justice Department informing them of an antitrust inquiry into a July deal with California, in which the two automakers along with Volkswagen and BMW agreed to stricter emissions standards than preferred by Trump. The Department of Transportation and the Environmental Protection Agency sent a letter to California saying the deal appears to violate the Clean Air Act and other laws.

“Congress has squarely vested the authority to set fuel economy standards for new motor vehicles, and nationwide standards for GHG (greenhouse gas) vehicle emissions, with the federal government, not with California or any other state,” the agencies wrote in a letter dated Friday to the California Air Resources Board, which oversees auto emissions in the state.

California has emerged as a leader of state-level efforts to block Trump administration moves weakening environmental protections. As part of those efforts, dozens of lawsuits have been filed challenging administration rollbacks.