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PacifiCorp, et al. v. Environmental Protection Agency, et al.

Paid petition · United States Court of Appeals for the Tenth Circuit, No. 23-9512 · judgment February 27, 2024


Decided · June 18, 2025
Pre-decision estimate: 43% cert probability (95% interval 30%–57%)

Before the decision, about 10.3× the 4.1% base rate. The model weighted this up for a petition filed soon after the judgment below, counsel who has won certiorari before, and a circuit split argued in the petition.

Question presented

Consolidated with 23-1067. Whether the Environmental Protection Agency's disapproval of a State Implementation Plan may only be challenged in the D.C. Circuit under 42 U.S.C. § 7607 (b)(1) if EPA packages that disapproval with disapprovals of other States' SIPs and purports to use a consistent method in evaluating the state-specific determinations in those SIPs.

Counsel of record

For petitioner
Misha Tseytlin
Troutman Pepper Locke LLP

For respondent
D. John Sauer
Solicitor General

Case

Conference history
Distributed for 4 conferences

Related
Vide, 23-1067

Argument & decision

Argued March 25, 2025 — Mithun Mansinghani · Misha Tseytlin · Malcolm L. Stewart. Audio and transcript

Decided June 18, 2025. Opinion by Thomas.

Proceedings

  1. Jul 21 2025
    Judgment Issued.
  2. Jun 18 2025
    Judgment REVERSED and case REMANDED. Thomas, J., delivered the opinion of the Court, in which Sotomayor, Kagan, Kavanaugh, Barrett, and Jackson, JJ., joined. Gorsuch, J., filed an opinion concurring in the judgment, in which Roberts, C. J., joined. Alito, J., took no part in the consideration or decision of the case. VIDED.
  3. Mar 25 2025
    Argued. For petitioners in 23-1067: Mithun Mansinghani, Oklahoma City, Okla. For petitioners in 23-1068: Misha Tseytlin, Chicago, Ill. For respondents: Malcolm L. Stewart, Deputy Solicitor General, Department of Justice, Washington, D. C. VIDED.
  4. Feb 19 2025
    CIRCULATED
  5. Feb 18 2025
    Reply of petitioners PacifiCorp, et al. filed. VIDED. (Distributed)
  6. Feb 12 2025
    Record requested from the United States Court of Appeals for the Tenth Circuit.
  7. Feb 12 2025
    Record received electronically from the United States Court of Appeals for the Tenth Circuit and available with the Clerk.
  8. Feb 10 2025
    SET FOR ARGUMENT on Tuesday, March 25, 2025. VIDED.
  9. Oct 21 2024
    Petition GRANTED. The petition for a writ of certiorari in No. 23-1067 is granted. The cases are consolidated, and a total of one hour is allotted for oral argument. Justice Alito took no part in the consideration or decision of these petitions. VIDED.
  10. Oct 21 2024
    Because the Court has consolidated these cases for briefing and oral argument, future filings and activity in the cases will now be reflected on the docket of No. 23-1067. Subsequent filings in these cases must therefore be submitted through the electronic filing system in No. 23-1067. Each document submitted in connection with one or more of these cases must include on its cover the case number and caption for each case in which the filing is intended to be submitted. Where a filing is submitted in fewer than all of the cases, the docket entry will reflect the case number(s) in which the filing is submitted; a document filed in all of the consolidated cases will be noted as “VIDED.”
  11. Oct 15 2024
    DISTRIBUTED for Conference of 10/18/2024.
  12. Oct 07 2024
    DISTRIBUTED for Conference of 10/11/2024.
  13. Sep 11 2024
    DISTRIBUTED for Conference of 9/30/2024.
  14. May 30 2024
    Reply of petitioners PacifiCorp, et al. filed.
  15. May 29 2024
    Rescheduled.
  16. May 28 2024
    DISTRIBUTED for Conference of 6/13/2024.
  17. May 23 2024
    Waiver of the 14-day waiting period for the distribution of the petition pursuant to Rule 15.5 filed by petitioner.
  18. May 21 2024
    Brief for the Federal Respondents filed. VIDED.
  19. Apr 24 2024
    Motion to extend the time to file a response is granted and the time is extended to and including May 21, 2024.
  20. Apr 23 2024
    Motion to extend the time to file a response from May 1, 2024 to May 21, 2024, submitted to The Clerk.
  21. Mar 28 2024
    Petition for a writ of certiorari filed. (Response due May 1, 2024)