Oklahoma v. EPA

Oklahoma v. Environmental Protection Agency
Supreme Court of the United States
Decided June 18, 2025
Full case name	Oklahoma v. EPA
Docket no.	23-1067
Citations	605 U.S. 609 ( more ) 145 S.Ct. 1720
Holding
EPA disapprovals of state implementation plans under the Clean Air Act are locally or regionally applicable actions, not national ones, so challenges to them should be heard in regional circuits.
Court membership
Chief Justice John Roberts Associate Justices Clarence Thomas  · Samuel Alito Sonia Sotomayor  · Elena Kagan Neil Gorsuch  · Brett Kavanaugh Amy Coney Barrett  · Ketanji Brown Jackson
Case opinions
Majority	Thomas, joined by Sotomayor, Kagan, Kavanaugh, Barrett and Jackson
Concurrence	Gorsuch (in judgment), joined by Roberts
Alito took no part in the consideration or decision of the case.
Laws applied
Clean Air Act

Oklahoma v. Environmental Protection Agency, 605 U.S. 609(2025), was a case before the Supreme Court of the United States that addressed where lawsuits challenging certain EPA actions must be filed. The Court held that when the EPA disapproves a state implementation plan (SIP) under the Clean Air Act, that decision is a local or regional action, not a national one. As a result, challenges must be brought in the appropriate regional federal appeals courts, rather than exclusively in the D.C. Circuit. ^{[1] [2]}

Background

In 2015, the EPA updated the National Ambient Air Quality Standards (NAAQS) for ozone. Under the Clean Air Act, each state was required to submit a plan explaining how it would meet the new standards.

The EPA rejected 21 of these state plans, including those from Oklahoma and Utah. The agency said legal challenges could only be heard in the D.C. Circuit. Several states, mostly Republican-led, disputed this interpretation and filed lawsuits in other regional courts. ^[3]

Decision

In a unanimous decision, the Court rejected the EPA’s position. ^[4] The justices held that each EPA disapproval of a state’s plan is a separate, discrete action under Section 7607(b)(1) of the Clean Air Act. Because these actions are locally or regionally applicable, challenges must be filed in the corresponding regional courts of appeals.

The Court noted that the EPA had made a similar argument in EPA v. Calumet Shreveport Refining (2025), which the justices had already rejected earlier that day. ^[2]

References

1. Oklahoma v. EPA,No. 23-1067 , 605 U.S. ___(2025).
2. Howe, Amy (June 18, 2025). "Supreme Court issues two rulings specifying where challenges to EPA actions on clean air must be filed". SCOTUSblog. Retrieved July 5, 2025.
3. Carter, M. Scott. "US Supreme Court to hear Oklahoma case tied to EPA rule dispute". The Oklahoman. Retrieved September 26, 2025.
4. "Supreme Court Lets EPA Air Pollution Battles Play Out in Regional Courts". Axios. June 18, 2025.

External links

• Text of Oklahoma v. EPA,No. 23-1067, 605 U.S. ___(2025) is available from: Justia