California Sues the Trump Administration in Its Escalating War Over Auto Emissions – The New York Times

The Trump administration is planning to roll back that standard to about 37 miles per gallon. But with the California waiver in place, California and the other states that follow its standard could keep that tighter fuel-economy requirement.

Mr. Wheeler, however, noted that under the Energy Policy and Conservation Act of 1975, states are not allowed to set fuel economy standards, and thus made the case that California’s separate fuel economy standards are illegal. Under that law, the authority to set mileage standards rests primarily with the Transportation Department.

“The statute says no state can have a state law or regulation that is related to fuel economy,” said Jeff Holmstead, who was a top E.P.A. official in the George W. Bush administration.

California and the other states maintain that the waiver to set standards on tailpipe greenhouse pollution was granted lawfully, within the authority granted by Congress under the Clean Air Act, and its revocation is unlawful.

“It is highly uncertain whether E.P.A. has the legal authority to withdraw a waiver. So that’s the first question,” said Mr. Gerrard, the Columbia University professor.

The California lawsuit also contends that those tailpipe standards are required for the state to control emissions of the other pollutants, such as soot and smog, at levels required to meet even federal standards. “We need the extra clean cars to meet the standards set by the federal government,” said Ms. Nichols. “If this prevails, millions of people in California will breathe dirty air. There will be more pollution, more asthma more hospitalizations, more premature deaths.”

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