The administration of US President Donald Trump is forging ahead with a plan to revoke a scientific finding that’s long been the cornerstone of US climate action.
Lee Zeldin, the head of the Environmental Protection Agency (EPA) who along with Trump has called for the “death of the Green New Scam,” unveiled the move at a car dealership in the US state of Indiana on Tuesday, hailing it as “the largest deregulatory action in the history of the United States.”
At the heart of the rollback is the Obama-era 2009 endangerment finding, grounded in the landmark Supreme Court case Massachusetts v. EPA. That ruling established the EPA has authority under the Clean Air Act to regulate greenhouse gases as air pollutants — a legal foundation for US efforts to curb emissions.
What’s at stake if the endangerment finding is reversed?
If the endangerment finding is thrown out, the EPA would lose its ability to use the Clean Air Act to regulate greenhouse gases, a move experts warn would represent a “radical pivot in American climate and energy policy.”
“It represents a complete US step away from renewable energy and energy efficiency in favor of full embrace of expanded production and use of fossil fuels, including coal, oil and natural gas,” Barry Rabe, environmental and public policy professor at the University of Michigan, told DW.
The second Trump administration is acting more aggressively in just about everything than the first, said Michael Gerrard, professor at Columbia Law School. It’s closely following the blueprint of Project 2025, a road map developed by conservative think tank, The Heritage Foundation. The 900-page document suggested an “update” of the endangerment finding.
The finding is the basis for rules regulating climate pollution established under the Obama and Biden administrations. Rules on power plants, vehicles, airplanes and landfills could now be repealed, said Jason Rylander, legal director of the Center for Biological Diversity’s Climate Law Institute.
At the same time, climate change continues to intensify across the US, fueling extreme heat, wildfires, floods and billion-dollar weather disasters.
“Climate change isn’t going away. We are rapidly accelerating past 1.5 degrees. There will be additional public health and environmental harms that will result from that,” said Rylander.
What will happen next?
The EPA has formally drawn up a proposal, which is now open for public comment until September. The agency will then review and respond to the feedback before issuing a final ruling, expected by the end of the year.
There will then likely be lawsuits. “Groups like mine will certainly sue,” said Rylander.
The cases will first go to the US Court of Appeals for the District of Columbia and could then be appealed to the US Supreme Court.
It could take years for the case to reach the Supreme Court. But once the EPA issues its final decision, the endangerment finding will be revoked, Gerrard told DW. “It stays revoked unless a court overturns it.”
Would the agency’s arguments hold up in court?
The endangerment finding is based on decades of scientific conclusions from credible global sources about the impacts of greenhouse gas emissions on climate change and public health. Rylander said the EPA was “slicing and dicing the statute to try to come up with some sort of loopholes,” and that none of the arguments brought forward “really passed the laugh test.”
Still, with a six-to-three conservative majority, the Supreme Court has repeatedly chipped away at federal climate regulations in recent years.
“So, it is possible that the Supreme Court will uphold this,” said Gerrard, who is also faculty director of the Sabin Center for Climate Change Law.
One argument the agency is using to reverse the finding is that its economic and political significance is so great that it requires explicit authorization from Congress. And while the EPA under Obama and Biden assumed it was enough to show that greenhouse gas emissions caused by humans endanger the climate, the Trump administration wants to evaluate each gas individually and by sector.
“And they are saying each chunk, like carbon dioxide from US power plants alone, has to endanger the climate,” Gerrard said, adding that this is much harder to establish. “So, a court that is hostile to climate regulation might follow that approach and agree with the Trump EPA and say that the endangerment finding is not valid.”
The EPA proposal also argues the 2009 finding failed to consider the benefits of CO2 emissions alongside their costs. Rylander called this “a fallacious argument,” comparing it to deciding whether a species is endangered under the Endangered Species Act.
“That’s not an economic decision. It’s a question of science,” he said, adding that it’s the same with pollutants, like CO2. “Do they cause public health harm or do they not?”
Will climate action continue in the US even if the finding is reversed?
Rabe said a reversal would cause “a chilling effect on many existing federal policies for greenhouse gas emissions.”
Still, the EPA would retain authority to regulate other pollutants such as sulfur dioxide, mercury and coal ash from coal-fired power plants.
“And many states are working to address pollution from cars and power plants, and they would do that under state law,” said Rylander, adding that “US efforts to decarbonize will still continue.”
However, Gerrard said, “the best tool they have would be gone.”
Edited by: Jennifer Collins
