n our crowded news cycle, it can be easy to miss key developments related to climate policy. So you would be forgiven for missing that the Supreme Court last month agreed to hear cases challenging the Environmental Protection Agency‘s authority to limit greenhouse gas emissions from power plants.

But environmental lawyers say you should be paying attention to the pending cases, which could threaten a key plank of President Biden’s climate agenda.

“This is potentially a very big deal,” Jeffrey Holmstead, a lawyer who ran the EPA’s Office of Air and Radiation under President George W. Bush, told The Climate 202.

Jonathan Adler, a professor at Case Western Reserve University School of Law, said the cases could offer an early test of the willingness of the Supreme Court’s six conservative justices to step in to block Biden’s climate plans. “It is definitely a big test,” Adler told The Climate 202.

The Supreme Court said Oct. 29 that it would hear the cases in response to requests from Republican-led states and the coal industry.

  • The requests were spearheaded by two Republican attorneys general — Patrick Morrisey of West Virginia and Wayne Stenehjem of North Dakota — as well as North American Coal and Westmoreland Mining.
  • The states and companies specifically asked the court to determine whether the EPA can issue sweeping climate regulations for the power sector under the Clean Air Act, which directs the agency to consider the “best system of emission reduction” for existing coal plants.
A long legal saga

The debate over the EPA’s Clean Air Act authority has inspired a years-long legal struggle spanning multiple Democratic and Republican administrations. Here’s a quick overview:

  • In 2015, President Barack Obama unveiled the Clean Power Plan, which took an expansive view of the agency’s authority under the law. The Obama administration found the “best system of emission reduction” included shifting from coal to cleaner-burning natural gas or renewable energy.
  • But in 2016, the Supreme Court put the Clean Power Plan on hold before it could take effect — and before litigation in a lower court could play out.
  • In 2019, President Donald Trump issued the Affordable Clean Energy (ACE) rule, which took a much narrower view of the EPA’s Clean Air Act authority. The Trump administration found the “best system of emission reduction” only consisted of changes at individual power plants — an approach known as “inside the fence line.”
  • But on the final day of the Trump administration, the U.S. Court of Appeals for the District of Columbia Circuit tossed out the ACE rule.