The U.S. Supreme Court announced Oct. 21 it will consider the jurisdiction of the U.S. Court of Appeals, D.C. Circuit, over three cases involving the Environmental Protection Agency’s Clean Air Act.

Under the current rules, the law requires the D.C. appeals court to hear challenges to nationally applicable regulations and cases that will have a national impact, while local and regional cases must be heard in regional courts, reported SCOTUSblog, a site focused on the Supreme Court.

The D.C. court of appeals is the primary jurisdiction for legal matters involving the energy industry and environmentalist concerns. Over the summer, the court struck down several FERC permits involving LNG projects and new gas pipeline infrastructure.

The high court’s order list includes three Clean Air Act cases. The EPA argues all three should be tried at the D.C. venue.

One of the cases, EPA v. Calumet Shreveport, involves a group of small Louisiana refineries that sought exemptions to the EPA’s Clean Air Act in June 2022. The EPA denied the exemptions, a move that was overturned by the 5th U.S. Circuit Court Appeals in New Orleans in November 2023. The EPA appealed the decision to the Supreme Court, arguing that the 5th Circuit was the incorrect venue for the hearing.

The high court combined the other two cases into one hearing.

In Oklahoma v. EPA and Pacificorp v. EPA, both states (Oklahoma and Utah) implemented pollution standards that the EPA rejected under the “Good Neighbor” provision of the Clean Air Act. The act requires states to reduce pollution that drifts into adjacent states.

In March 2023, the EPA announced the act, meant to reduce ozone and smog-forming gases, according to the agency’s announcement.

Afterwards, 21 states brought suits against the act, and the Supreme Court ruled the law could not be implemented pending the outcome of the hearing, the Associated Press reported. Utah and Oklahoma are arguing that the case should be tried in their regional court in Colorado, as opposed to the D.C. court.