President Trump announced on Wednesday, September 18, that the state of California could no longer set vehicle emissions standards. The move comes as the Trump administration also prepares to roll back the Corporate Average Fuel Economy, or CAFE, standards set under President Barack Obama. 

“The Trump Administration is revoking California’s Federal Waiver on emissions in order to produce far less expensive cars for the consumer, while at the same time making the cars substantially SAFER,” Trump tweeted Wednesday morning. 

The Trump Administration is revoking California’s Federal Waiver on emissions in order to produce far less expensive cars for the consumer, while at the same time making the cars substantially SAFER. This will lead to more production because of this pricing and safety……

— Donald J. Trump (@realDonaldTrump) September 18, 2019

Trump noted that there would be very little difference in emissions between the California Standard and the new U.S. Standard. Trump anticipates the move will lead to “older, highly polluting cars” being replaced by “new, extremely environmentally friendly cars.”

California’s ability to set emissions standards more stringent than the federal government’s goes back to a waiver Congress issued when the Clean Air Act passed in 1970. The state has long pushed automakers to create more fuel-efficient passenger vehicles and recently began requiring the auto industry to start rolling out fleets of zero-emission vehicles, including plug-in hybrids, pure battery-electric vehicles, and hydrogen-powered cars.

Earlier this month, the Justice Department announced its investigation into a deal that the California Air Resources Board (CARB) made with four automakers — Ford, VW, Honda, and BMW. The agreement would hold them to stricter emissions and mileage standards than the Trump revised CAFE mandate.

The Environmental Protection Agency, one of the two agencies charged with regulating federal mileage standards, said the agreement automakers made with California was a “PR stunt.”

“You have no basis and no authority to pull this waiver,” California Attorney General Xavier Becerra said referring to Trump. Becerra added, “we’re ready to fight for a future that you seem unable to comprehend.”

Other states that have adopted California emissions standards.

California has already filed legal efforts to stall such a move with support from other states that have adopted its stricter mandates.

Trump also aims to relax Obama-era federal mileage standards nationwide.

Under Trump, emissions requirements for new cars and trucks would remain at 37 mpg, the current 2020 level through 2026. During the Obama-era, emissions requirements called for a fleetwide fuel efficiency average of 46.7 miles per gallon by 2025, with annual average increases of about 5-percent. A “mid-term review” was included to evaluate whether the goal remained possible. 

With the rapid shift from passenger cars to less fuel-efficient pickups and utility vehicles, several automakers began pressing for a rollback, a request the outgoing administration rejected.  

“We embrace federalism and the role of the states, but federalism does not mean that one state can dictate standards for the nation,” EPA Administrator Andrew Wheeler told the National Automobile Dealers Association. 

“One national standard will provide much-needed regulatory certainty to automakers, dealers, and consumers,” Wheeler said.

Wheeler added the EPA and U.S. Transportation Department would take action “very soon to bring clarity to the proper — and improper — scope and use of the Clean Air Act preemption waiver.”