Public health, green groups sue EPA over rollback of rules supporting climate protection

WASHINGTON (AP) — A coalition of health and environmental groups sued the Environmental Protection Agency on Wednesday, challenging the reversal of a scientific finding that has been the central basis for U.S. action to regulate greenhouse gas emissions and fight climate change.

A rule finalized by the EPA last week revokes a 2009 government statement known as the threat finding that determined carbon dioxide and other greenhouse gases threaten public health and welfare. The Obama-era finding is the legal underpinning of almost all climate regulations under the Clean Air Act for motor vehicles, power plants and other pollution sources that heat the planet.

The repeal eliminates all greenhouse gas emissions standards for cars and trucks and could trigger a broader unwinding of climate regulations on stationary sources such as power plants and oil and gas facilities, experts say.

The legal challenge, filed in the U.S. Court of Appeals for the District of Columbia Circuit, alleges that the EPA’s revocation of the threat finding is illegal. The 2009 finding supported common-sense precautions to reduce climate pollution, including from cars and trucks, the lawsuit said. Clean vehicle standards imposed by the Biden administration are set to deliver “the single largest reduction in U.S. carbon pollution in history, save lives and save Americans hard-earned money on gas,” the coalition said in the suit’s filing.

After nearly two decades of scientific evidence supporting the 2009 finding, “the agency cannot credibly claim that the body of work is wrong now,” said Brian Lynk, a senior attorney at the Environmental Law & Policy Center.

“This reckless and legally unsustainable decision creates immediate uncertainty for businesses, guarantees protracted legal battles, and undermines the stability of federal climate regulations,” Lynk said.

The Supreme Court ruled in a landmark 2007 case that carbon dioxide and other greenhouse gases are “air pollutants” under the Clean Air Act. Since the Supreme Court’s decision, in a case known as Massachusetts v. EPAcourts have uniformly rejected legal challenges to the threat finding, including a 2023 decision by the DC Court of Appeals.

EPA representative Brigit Hirsch said Wednesday that the agency “carefully considered and evaluated the legal basis of the 2009 Threat Finding” in light of recent court decisions, including a 2022 Supreme Court ruling that limited how the Clean Air Act can be used to reduce carbon dioxide emissions from power plants.

“EPA is bound by the laws established by Congress, including under the Clean Air Act,” she said. “Congress never intended to give EPA authority to set (greenhouse gas) regulations for cars and trucks.”

The dispute is likely to end up again before the Supreme Court, which is now much more conservative than it was in 2007.

Trump administration claims the finding has ‘strangled’ business

The lawsuit was brought by groups including the American Public Health Association, American Lung Association, Alliance of Nurses for a Healthy Environment and Physicians for Social Responsibility, along with environmental groups such as the Center for Biological Diversity, Conservation Justice Foundation, Environmental Defense Fund, Natural Resources Defense Council and Sierra Club.

The suit named the EPA and its administrator Lee Zeldin as defendants.

In announcing the repeal, President Donald Trump said it was “by far the single largest deregulatory action in American history,” while Zeldin called the threat “the Holy Grail of federal regulatory overreach.”

The threat finding “resulted in billions of dollars in regulations strangling across sectors of the US economy, including the US auto industry,” Zeldin said. “The Obama and Biden administrations have used it to push a left-wing wish list of costly climate policies, electric vehicle mandates and other requirements that have eroded consumer choice and affordability.”

Environmental groups described the move as the single biggest attack in US history against federal authority to address climate change. Evidence supporting the threat finding has only grown stronger in the 17 years since it was approved, they said.

Finding of threat spurred new climate regulations

Under the Clean Air Act, the EPA is legally required to limit the emission of any air pollutant that causes or contributes to “air pollution that could reasonably be expected to endanger public health or welfare.”

In its 2007 ruling, the Supreme Court told EPA to determine, based on science, whether greenhouse gas pollution endangers human health and welfare. EPA made that determination in 2009, leading to new standards for vehicles. It built on that finding when other standards were issued.

EPA’s revocation of the threat finding, along with the elimination of safeguards for vehicle-restricted emissions, “clearly shows a complete failure of the agency’s mission to protect people’s health and its legal obligations under the Clean Air Act,” said Gretchen Goldman, president and CEO of the Union of Concerned Scientists, which is part of the suit.

“These shameful and dangerous actions … are rooted in falsehoods, not facts, and are completely contrary to the public interest and the best available science,” Goldman said. Heat-trapping emissions and global average temperatures are rising — mainly due to the burning of fossil fuels — contributing to an increasing human and economic toll around the world, she said.

The White House and Zeldin said the new rule would save taxpayers $1.3 trillion over the next three decades, mostly from reduced costs for new vehicles. But the EPA’s own analysis found that eliminating the vehicle standards would likely raise gas prices, forcing Americans to spend more on fuel. A chart within the agency’s regulatory analysis projects $1.4 trillion in additional costs by 2055 from increased fuel purchases, vehicle repair and maintenance and other issues.

Democrats begin investigation into EPA action

The lawsuit comes as Senate Democrats have announced they are start investigation in the decision, saying public comments by Zeldin and other Trump officials over the past year make it clear that the administration “viewed reconsideration of the threat finding as a predetermined goal” long before it completed its required regulatory review, including consideration of nearly 600,000 public comments.

Many of the comments submitted to EPA “outlined the scientific and legal problems of revoking the threat finding,” Rhode Island Sen. Sheldon Whitehouse and other Democrats said.

Whitehouse, the top Democrat on the Senate Environment Committee, is leading the inquiry along with 40 other senators.

“When an agency signals that the outcome of a proceeding is predetermined, public participation becomes performative rather than meaningful, undermining the legitimacy of the rulemaking process and violating basic principles of administrative law,” the Democrats said in a letter to Zeldin.

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