The battle lines have been drawn in the escalating legal conflict surrounding the Environmental Protection Agency’s (EPA) decision to reverse its pivotal ‘endangerment finding.’ This finding has long served as the bedrock of federal climate change regulations, and its recent rollback signals a major shift in environmental policy.
On Wednesday, a coalition of environmental and public health organizations initiated legal action in the U.S. Court of Appeals for the District of Columbia Circuit. Their lawsuit contends that the EPA’s move to remove limitations on greenhouse gas emissions from vehicles and other potential sources is unlawful. This legal challenge directly responds to the EPA’s recent decision to discard its fundamental scientific conclusion – the ‘endangerment finding’ – which affirmed that greenhouse gases pose a significant threat to public health. For years, this finding underpinned crucial climate regulations across the nation.
The core of the lawsuit asserts that the agency is simply recycling arguments that the Supreme Court previously reviewed and dismissed in the pivotal 2007 case, Massachusetts v. E.P.A. This contentious issue is widely anticipated to return to the Supreme Court, whose current composition is considerably more conservative than it was at the time of the original ruling.
During the 2007 Massachusetts v. E.P.A. case, the Supreme Court justices mandated that the EPA must scientifically determine whether greenhouse gases posed a public health threat under the 1970 Clean Air Act, and if so, regulate them accordingly. Following this directive, the EPA published its ‘endangerment finding’ in 2009, enabling the federal government to establish limits on these climate-warming emissions.
“With this action, EPA completely reverses its fundamental mission,” stated Hana Vizcarra, a senior lawyer at Earthjustice, the nonprofit representing six groups in the lawsuit. “It is forsaking its primary duty to safeguard human health and the environment, instead opting to bolster polluting industries and, in doing so, attempting to rewrite established law.”
Despite concerns surrounding the current ideological leanings of the Supreme Court, William Piermattei, managing director of the Environmental Law Program at the University of Maryland Francis King Carey School of Law, stressed that environmental advocates “absolutely must challenge this” legal maneuver.
Piermattei emphasized that failing to challenge the decision would effectively mean “agreeing that we should not regulate greenhouse gases under the Clean Air Act, period.” He further added, “I don’t believe any environmentalist, and indeed a majority of the public, would concur with such a statement.”
Should the environmental groups and numerous Democratic states planning similar lawsuits be unsuccessful, the responsibility for regulating greenhouse gases at a national level would then fall squarely on Congress.
The EPA, in its final rule on the finding, presented the argument that Congress should take action. This stance was publicly declared at the White House on Thursday by Administrator Lee Zeldin and President Trump. Zeldin highlighted that two distinct Supreme Court rulings since 2007 have fundamentally altered the legal interpretation surrounding the endangerment finding.
One of these rulings established that Congress must intervene on “major questions” that carry substantial political and economic consequences, a category into which the EPA’s rules undeniably fall. The second ruling suggested that courts are not obligated to grant the same level of deference to the decisions made by federal agencies as they once did.
The EPA had not yet responded to requests for comment regarding the lawsuit.