More and more states and automakers are uniting behind California in a nationwide debate over vehicle emissions standards, as tensions between the Golden State and President Donald Trump’s administration come to a head.

A growing coalition of states is supporting California’s efforts to demand cleaner and more efficient vehicles, at a time when the Environmental Protection Agency (EPA) and the National Highway Traffic Safety Administration (NHTSA) are seeking to halt standards despite objections from health and climate experts. Those states are now being joined by several major automakers, with others facing pressure from lawmakers.

Three weeks ago, California inked a deal with four major automakers, committing them to increasing both gas mileage and greenhouse gas emissions standards in exceedance of the Trump administration’s proposal. Now, others are under pressure to do the same.

Eight senior House Democrats wrote to 14 other automakers on Thursday, encouraging them to sign on to the same deal California made with Ford, BMW, Honda, and Volkswagen.


“Our districts and the country as a whole need the auto industry to help us address climate change, and in the near-term that means a serious commitment to greenhouse gas reduction through emission reduction from vehicles,” wrote lawmakers led by Reps. Doris Matsui (D-CA) and Paul Tonko (D-NY), the latter of whom is chairman of the House Energy and Commerce Environment and Climate Change Subcommittee. Recipients included major automakers like Volvo, Chrysler, and Toyota.

That appeal echoes an earlier effort from 30 Senate Democrats, who last week similarly called on automakers to join their peers in adhering to stricter standards.

“In the absence of an agreement between the Federal government and states, the California agreement is a commonsense framework that provides flexibility to the industry to meet tailpipe standards while also taking important steps to reduce greenhouse gas emissions and save money on fuel for consumers,” that letter reads.

The deal the California Air Resources Board (CARB) struck with the four automakers would see the average fuel economy of fleets increase to 50 miles per gallon by 2026. That commitment is less than Obama-era efforts, which would have seen 54.5 miles per gallon by 2025, but it still marks a major break with the Trump administration.


Under the Clean Air Act, California has for decades been granted a waiver allowing the state to impose vehicle emissions standards exceeding those of the federal government. But the Trump administration has sought to undermine the state with its proposed Safer Affordable Fuel-Efficient (SAFE) Vehicles Rule. The EPA and NHTSA are proposing freezing federal fuel economy standards at 2020 levels, a move environmental and public health experts have said would have swift repercussions. Data shows that air quality has improved significantly as a result of the stricter standards.

California has aggressively sought to protect its standards, suing the federal government over the rollback. And automakers have an incentive to side with California. While the oil and gas industry has lobbied hard for easing emissions standards, many automakers have grown worried by the scope of the administration’s rollbacks. One serious concern has been the prospect of a split market, wherein the industry would have to meet different standards in different states. In June, 17 car companies wrote to Trump and warned that weakening standards regardless could destabilize the industry.

Support from other states is also giving California a boost. Twelve states and Washington, D.C., were already committed to California’s standards prior to the Trump administration. But Colorado, an oil-rich state, recently joined that lineup, becoming a “Section 177 state” in a nod to the section of the Clean Air Act that allows for California’s stricter standards. New Mexico, another oil state, also has plans to re-join by the end of 2020; the state had initially joined but repealed the standards under Republican Gov. Susana Martinez. Arizona and Florida have similarly adopted and then repealed the standards.

Environmental groups have expressed optimism that other states may adopt California’s approach, especially amid growing concerns over the potential ramifications of the rollback. Research released last week by the environmental policy group Energy Innovation found that the Trump administration’s efforts could cost the U.S. economy $400 billion through 2050, in addition to increasing U.S. transport emissions up to 10% by 2035.

And with litigation underway, conversations about auto emissions and climate change are already proving contentious. The Washington Post reported on Friday that a federal judge who was set to hear the vehicle emissions case between the EPA and the consortium of 17 states led by California was replaced on that panel after he sent emails critical of climate science. The judge, A. Raymond Randolph, had complained in a reply-all email to a colleague about a seminar on climate change science for judges.

“The jurisdiction assigned to you does not include saving the planet. A little hubris would be welcomed in many of your latest public displays,” Randolph wrote. “The supposedly science and stuff you are now sponsoring is nothing of the sort. Get out of this business and back into the business of judging, which is what you are being paid to do.”

Randolph has been replaced on the panel by Sri Srinivasan, a Barack Obama appointee.