Kavanaugh's emissions opinion invites future challenges from fossil fuel producers

The U.S. Supreme Court's latest climate ruling may have left California's emissions rules intact--for now--but legal experts say it sets the stage for a new wave of lawsuits from fossil fuel producers that could ultimately dismantle the state's ability to lead on environmental regulation.

Dan Becker, the director of the Safe Climate Transport Campaign at the Center for Biological Diversity, said Monday the court has opened a "Pandora's box" that could significantly change who has standing to sue and create a chaotic litigation landscape.

"Whether they punted or whether they put it off for another day, one can only speculate," Becker said. "The court doesn't usually go further than they need to in order to dispose of a case."

The Supreme Court ruled 7-2 on Friday that fuel producers have standing to challenge a federal program allowing California to set its own vehicle emissions limits. The decision turned on whether the challengers had shown sufficient injury to sue. Diamond Alternative Energy, LLC v. Environmental Protection Agency, 2025 DJDAR 5374 (U.S., filed June 20, 2025).

"This case concerns only standing, not the merits," Justice Brett Kavanaugh wrote for the majority. "EPA and California may or may not prevail on the merits in defending EPA's approval of the California regulations. But the justiciability of the fuel producers' challenge to EPA's approval of the California regulations is evident. Courts should not 'make standing law more complicated than it needs to be.' Thole v. U.S. Bank N. A., 590 U. S. 538, 547 (2020)."

A variety of business and conservative groups, ranging from the National Federation of Independent Business to the Alliance Defending Freedom quickly hailed Kavanaugh's opinion.

"California's EV mandates are unlawful and bad for our country," Chet Thompson, president and CEO of the American Fuel & Petrochemical Manufacturers, said in a statement. "Congress did not give California special authority to regulate greenhouse gases, mandate electric vehicles or ban new gas car sales--all of which the state has attempted to do through its intentional misreading of statute."

Thompson added, "We look forward to finally having our day in court."

"Despite the ongoing legal fight, California consumers and our economy remain exposed to the cost impacts of these mandates," Rob Lapsley, president of the California Business Roundtable, said in an email on Monday.

Becker called the ruling an invitation for polluters to sue.

"When they sue, then of course the court will get to the merits. I don't think they're enthusiastic about California's system and clearly Kavanaugh was signaling that he doesn't have a lot of respect for Massachusetts v. EPA," he said.

In Massachusetts v. Environmental Protection Agency, 549 U.S. 497 (2007), the court established that greenhouse gas emissions are pollutants subject to regulation by the agency. The 5-4 ruling found that the EPA had this authority under the Clean Air Act, even though the 1963 federal law did not mention greenhouse gases and was written in a time before human-caused climate change was a widespread concern.

Kavanaugh did not mention Massachusetts in his majority ruling. But both rulings include extensive discussions of standing. In Massachusetts, Chief Justice John Roberts dissented. He wrote that the state should lack standing to sue because the harms of climate change were not "concrete or particularized."

Some environmental groups said Friday's ruling could have been worse for them. The court did not rule on the question of whether California has the authority to set its own emissions limits.

"The court was asked to take up the merits, and it declined," said Andrea S. Issod, senior attorney with the Sierra Club's Environmental Law Program in Oakland, in an email. "SCOTUS did not take on the states' equal sovereignty claim, which the D.C. Circuit rejected."

But in Diamond, Kavanaugh found the potential harm to oil companies was concrete, particularized and imminent.

"The fuel producers assert that the California regulations reduce the manufacture and sale of cars powered by gasoline and other liquid fuels, thereby causing a decrease in sales of those fuels by the fuel producers," he wrote.

Kavanaugh concluded, "The government generally may not target a business or industry through stringent and allegedly unlawful regulation and then evade the resulting lawsuits by claiming that the targets of its regulation should be locked out of court as unaffected bystanders."

Adrian Martinez, deputy managing attorney with Earthjustice, said the ruling is troubling because it reaches years to challenge waivers dating to 2012. If successful, he said, these companies could win rulings that demand California not comply with the Clean Air Act.

"Federal law requires the state to meet those standards, so California needs to do things like adopt standards for cars, trucks and other equipment to make it safe to breathe as federal law requires," Martinez said. "I think what we're seeing now is efforts by the oil industry and even the federal government itself to interfere with the ability of California to protect its residents and comply with federal law."

Kavanaugh noted that the Environmental Protection Agency did not challenge the oil companies' standing. But California and other states did and won in the lower court. They argued that because of "surging demand" for electric vehicles, the oil producers failed to show that reversing the rules would help them sell more fuel.

Then Trump won the election, Kavanaugh wrote. The new administration quickly attempted to reverse California's waivers and asked the court to hold the case in abeyance. Trump's "Big Beautiful Bill" would reverse a $7,500 federal tax credit for electrical vehicles, which could undermine California's demand argument.

Becker said that Kavanaugh's ruling takes such an expansive view of standing that "everybody could say that they have an interest in pretty much any legislation or regulation." He added that this could include rules on issues like worker safety, not just issues that affect pollution that drifts across borders.

"It's not great news for anybody with lungs," Becker said. "Yes, this initial ruling is limited. But it doesn't point in a direction that can bring solace to anybody who cares about healthy air and a healthy climate."