"WASHINGTON - The U.S. Justice Department has issued civil subpoenas to four major automakers, demanding that they disclose details on a deal struck with California in July to follow strict vehicle emissions standards, a source briefed on the matter said on Thursday.
The Justice Department is carrying out an antitrust investigation into the voluntary agreement. It comes against a growing number of fights between the Republican White House and California on a number of fronts, including numerous environmental issues.
The Trump administration in September issued a determination that California cannot set its own vehicle emission standards and zero-emission vehicle mandates and is investigating if the companies engaged in anti-competitive conduct in striking the deal. "
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