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Supreme Court decisions
No. 23-1067Jun 18, 2025Environmental ProtectionReversed

The question

Whether EPA's disapprovals of the Oklahoma and Utah state implementation plans under the Clean Air Act are locally or regionally applicable actions reviewable in a regional Circuit rather than the D.C. Circuit.

Oklahoma v. EPA

What the Court decided

The Court held that EPA's disapprovals of the Oklahoma and Utah state implementation plans are locally or regionally applicable actions, so challenges to them may be brought in a regional Circuit. Each SIP disapproval is its own Clean Air Act action, undertaken under the same authority as a SIP approval, and a SIP disapproval applies only to the State that proposed the plan. EPA's choice to aggregate its disapprovals into one omnibus Federal Register rule does not change the venue analysis, because the statute makes the Act's framing of the relevant action controlling regardless of how EPA packages its decisions.

How the justices split

8-0
In favor 8Did not take part 1
Thomas
Sotomayor
Kagan
Kavanaugh
Barrett
Jackson
Gorsuch
Roberts
Alito

The Court's opinion

Thomas, joined by Sotomayor, Kagan, Kavanaugh, Barrett, Jackson

Applying the two-step venue framework from EPA v. Calumet Shreveport Refining, the Court identified the relevant EPA action by reference to the Clean Air Act provision under which EPA acted rather than how EPA presented its decision. Each SIP disapproval is its own action taken under the same authority as a SIP approval, which the statute lists as a prototypical locally or regionally applicable action, and applies only to the State that proposed the plan. EPA's aggregation of its disapprovals into one omnibus Federal Register rule has no significance for venue, so the Oklahoma and Utah disapprovals are reviewable in a regional Circuit.

Concurring in the judgment

Gorsuch, joined by Roberts

Gorsuch agreed with the judgment that the disapprovals are reviewable in a regional Circuit but wrote separately rather than joining the opinion of the Court.

How we know · 5 sourced claims
  • The Court held that EPA's disapprovals of the Oklahoma and Utah SIPs are locally or regionally applicable actions reviewable in a regional Circuit.

    Source: syllabus, Held

  • The Court applied the two-step venue inquiry under Section 7607(b)(1) drawn from EPA v. Calumet Shreveport Refining, L.L.C., 605 U.S. 627.

    Source: syllabus, Held

  • Each EPA SIP disapproval constitutes its own action because EPA undertakes disapprovals under the same Clean Air Act authority underlying SIP approvals.

    Source: syllabus, Held

  • EPA's aggregation of its SIP disapprovals into one omnibus Federal Register rule has no significance for venue purposes.

    Source: syllabus, Held

  • Thomas delivered the opinion of the Court joined by Sotomayor, Kagan, Kavanaugh, Barrett, and Jackson; Gorsuch filed an opinion concurring in the judgment joined by Roberts; Alito took no part.

    Source: syllabus, lineup

Read the opinion on supremecourt.gov