Can California Set Its Own Air Pollution Rules?

The House of Representatives on Thursday voted to block California rules that would ban the sale of new gas-powered vehicles by 2035. The vote was 246 to 164, with 35 Democrats joining Republicans to approve the measure.

If the Senate also votes to block California’s E.V. plan, the decision could have wide-reaching effects, including for the 11 other states that have adopted the Golden State’s standards. Together, these states make up more than 40 percent of the U.S. auto market.

Under the 1970 Clean Air Act, California can receive waivers to pass air-pollution standards that are stricter than the national rules.

California’s ban on the sale of new gas-powered cars is one of the most ambitious climate policies in the nation. “The California waiver is very, very important, especially since motor vehicles are now the single largest source of greenhouse gas emissions in the United States,” said Michael Gerrard, director of the Sabin Center for Climate Change Law at Columbia University.

The regulations are expected to help speed the transition to electric vehicles and requires automakers to ensure that zero-emission, plug-in hybrid, or hydrogen-powered vehicles make up 35 percent of new passenger cars and light trucks they sell starting next year. In 2024, about one in four cars registered in California were electric.

California’s climate policies have drawn the ire of the Trump administration and Republicans in Congress, in part because they can influence large swaths of the economy far from the West Coast.

In holding the vote, the House ignored a decision from the Government Accountability Office, an independent government watchdog. The Senate parliamentarian, a nonpartisan adviser to the body on rules and procedures, has also said that Congress cannot use its proposed method to block California’s plans.

A 50-year-old waiver system

When Congress passed the Clean Air Act in 1970, California had the worst air pollution in the nation. And while the legislation prevented all other states from establishing their own air quality standards, legislators made an exception for smog-choked California.

Under the law, California can ask the Environmental Protection Agency for a waiver if it wants to establish its own, stricter emissions standards for cars and trucks. As of 2024, it had received more than 100 waivers. Other states are allowed to adopt California rules under certain circumstances.

These waivers were the legal mechanism through which California (and then other states) established limits on future sales of gas-powered cars. The state has also used waivers to limit emissions from trucks.

In 2019, the first Trump administration revoked California’s waiver for the first time. The Biden administration reinstated it in March 2022.

What could happen to E.V. sales?

California’s air quality regulator has estimated that the state’s regulations would cut statewide greenhouse gas emissions from cars, pickup trucks, and S.U.V.s in half by 2040.

But California’s E.P.A. waiver is not the most consequential policy affecting E.V. sales in the U.S., according to a recent analysis from Harvard University’s Salata Institute for Climate and Sustainability. Getting rid of the waivers is projected to affect E.V. market share by 2030 by less than 1 percent.

Until recently, several initiatives were working together to remove some of the biggest barriers to widespread electric vehicle adoption. The federal government provided $3 billion to build E.V. chargers on highways. The 2022 Inflation Reduction Act offered tax incentives for consumers, which brought prices closer to gas-powered vehicles. And other tax credits for critical minerals and batteries were bringing costs down for automakers.

But the Trump administration has paused spending on highway chargers, and other incentives, like the E.V. tax credits, may soon face rollback attempts in Congress.

“When you take away multiple different policies, they have compounding effects that’s bigger than the sum of taking away each policy,” said Elaine Buckberg, an economist and senior fellow at Harvard and co-author of the analysis.

Perhaps most important feature of the California requirements is their function as a backstop to federal spending. If the federal funding and tax incentives go away, but California waivers remain in place, automakers would still have to transition to meet the mandates.

Even without the extra support of California’s rules, Buckberg said, E.V. sales are projected to grow. Current estimates show E.V.s making up 48 percent of car sales by 2030.

But if the waivers, the highway charger funding, and the tax credits all went away, Buckberg’s analysis suggests, E.V. market share would still reach 32 percent by that time — more than triple what it was in 2024.

Lost Science

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Please reach out to climateforward@nytimes.com or respond to this email, and tell us what you were working on, the current status of your job or grant, and whether you’re willing to talk on the record.

The Trump administration

Fact-checking the ‘President who follows science’

On Earth Day, the White House posted a page on its website titled, “We Finally Have a President Who Follows Science.”

The New York Times annotated a selection of the statements on that page to fact-check those claims. The White House did not respond to a detailed list of questions.

In the first hours of his second term, President Trump withdrew the United States from the Paris climate agreement and the World Health Organization. Since then, the Trump administration has slashed budgets for federal science and health agencies, fired federal scientists, censored research and threatened universities, and dismissed hundreds of volunteer scientists who were preparing an important update to the country’s flagship climate assessment.

The president has said his goals are to minimize the regulations that have stifled industry, and to promote more energy production, which he sees as central to economic growth. — Rebecca Dzombak

Read more.

Regulations

Days after Trump commits to seabed mining, two sides face off

Less than a week after President Trump signed an executive order to accelerate seabed mining, the U.S. government received its first permit application from the Metals Company, one of the most ardent proponents of the as yet unproven practice.

On Tuesday, the company’s chief executive, Gerard Barron, was also on hand in Washington for a contentious hearing in front of the House Natural Resources Committee.

He likened Mr. Trump’s move to a “starting gun” in the race to extract minerals like cobalt and nickel from potato-size nodules lying in the frigid, pitch-black, two-and-a-half-mile-deep sands of the Pacific Ocean floor.

Republican and Democratic committee members clashed over how much weight should be given to environmental concerns about the practice. The Trump administration has said it will consider issuing permits for mining in territorial U.S. waters and also in international waters. — Max Bearak

Read more.