Clean Air Act Citizen Suits Require Ongoing or Repeated SIP Violations—Purely Prospective Noncompliance Is Not Actionable Under § 7604(a)(1)

I. Introduction

Gordon-Darby Holdings, Inc. v. Quinn is a First Circuit stay-pending-appeal order arising from New Hampshire’s repeal of its motor vehicle emissions inspection and maintenance program (the “I/M program”) through House Bill 2, effective January 31, 2026. Gordon-Darby Holdings, Inc. (the parent of the State’s sole I/M vendor) sued state officials—Commissioners of the New Hampshire Department of Safety and Department of Environmental Services (the “Commissioners”)—under the Clean Air Act (“CAA”) citizen-suit provision, 42 U.S.C. § 7604(a), seeking to prevent termination of I/M implementation.

The district court issued a preliminary injunction requiring the Commissioners to continue implementing and enforcing the I/M program notwithstanding the repeal. The Commissioners sought a stay pending appeal. The central legal issues at the stay stage were:

  • Whether Gordon-Darby plausibly alleged that the Commissioners were “in violation of” an “emission standard or limitation” under 42 U.S.C. § 7604(a)(1), where the claimed SIP breach was either (i) based on state communications about the future end of the program, (ii) based on termination of the vendor contract, or (iii) based on an anticipated future lapse when the repeal became effective.
  • Whether the extraordinary remedy of a preliminary injunction—compelling a State to keep enforcing a repealed program—should be stayed under the four-factor test for stays pending appeal.

II. Summary of the Opinion

The First Circuit granted the Commissioners’ motion to stay the preliminary injunction pending appeal. Applying the four-factor stay framework, the court held that the Commissioners made the required “strong showing” of likely success on the merits, principally because Gordon-Darby did not adequately allege a cognizable violation actionable under § 7604(a)(1).

The court further found irreparable injury to the State from an injunction preventing implementation of a statute enacted by the State’s representatives. It also concluded that the balance of harms and public interest favored a stay because the injunction did not guarantee restoration of Gordon-Darby’s contract and the asserted private harms were speculative.

III. Analysis

A. Precedents Cited

  • Rhode Island v. Trump, 155 F.4th 35 (1st Cir. 2025) and New York v. Trump, 133 F.4th 51 (1st Cir. 2025)
    These cases supply the First Circuit’s contemporary articulation of the stay-pending-appeal framework, emphasizing that a stay is an “intrusion” into normal judicial processes and that the first two factors—likelihood of success and irreparable injury—are “the most critical.” The court uses them to set a demanding posture: the Commissioners must justify extraordinary relief.
  • Nken v. Holder, 556 U.S. 418 (2009)
    The court treats Nken as the controlling Supreme Court authority for the four stay factors and for the proposition that the movant bears the burden. The opinion draws directly from Nken for both the factor test and the “most critical” characterization of the first two factors.
  • Somerville Pub. Schs. v. McMahon, 139 F.4th 63 (1st Cir. 2025)
    Cited alongside Nken and Rhode Island for the same burden-and-factors framework.
  • Env't Integrity Project v. EPA, 969 F.3d 529 (5th Cir. 2020) and Luminant Generation Co. v. EPA, 675 F.3d 917 (5th Cir. 2012)
    These authorities are invoked to characterize the CAA as “cooperative federalism.” They function as background: the case concerns the federal enforceability of state commitments embedded in a State Implementation Plan (“SIP”), and the limits of citizen enforcement.
  • Conservation L. Found. v. Acad. Express, LLC, 129 F.4th 78 (1st Cir. 2025)
    This First Circuit precedent grounds two key points: (i) the CAA’s division of responsibilities between states and the federal government; and (ii) once approved by EPA, a SIP becomes part of federal law—explaining why SIP-related duties may be enforceable through federal mechanisms, including (within statutory limits) citizen suits.
  • Cotto v. Campbell, 126 F.4th 761 (1st Cir. 2025)
    Cited for the proposition that suing state officials in their official capacities can avoid certain Eleventh Amendment barriers (i.e., the familiar path for prospective relief against state officers).
  • Gwaltney v. Chesapeake Bay Foundation, 484 U.S. 49 (1987)
    The opinion’s core merits-likelihood analysis turns on Gwaltney. The district court relied on it to support the view that a future violation could satisfy “to be in violation” language. The First Circuit, however, reads Gwaltney as requiring allegations of a continuous or intermittent violation grounded in past conduct—i.e., a “reasonable likelihood that a past polluter will continue to pollute in the future”—not a suit based solely on anticipated noncompliance by an entity with a “clean record of regulatory compliance” at the time of filing.
  • Pawtuxet Cove Marina, Inc. v. Ciba-Geigy Corp., 807 F.2d 1089 (1st Cir. 1986)
    Used to reinforce the First Circuit’s understanding of citizen-suit jurisdiction in present-tense statutory schemes: the plaintiff must “fairly allege” a continuing likelihood of future violation in light of prior violations. The court underscores that it did not suggest jurisdiction where the only asserted wrong is a “possible future violation.”
  • Nat. Res. Def. Council v. Texaco Refin. & Mktg., Inc., 2 F.3d 493 (3d Cir. 1993)
    Addressed and distinguished because it involved allegations of past and ongoing violations; it therefore does not support citizen suits based on purely prospective violations.
  • Maryland v. King, 567 U.S. 1301 (2012) and New Motor Vehicle Bd. of Cal. v. Orrin W. Fox Co., 434 U.S. 1345 (1977)
    These in-chambers authorities are used on irreparable harm: a State suffers irreparable injury when enjoined from effectuating statutes enacted by its representatives. They bolster the conclusion that forcing New Hampshire to keep administering a repealed program is a paradigmatic irreparable injury for stay purposes.
  • Hate to Paint, LLC v. Ambrose Dev., LLC, No. 2023-0076, 2024 WL 4765322 (N.H. Nov. 13, 2024)
    Cited for the contractual concept of “termination for convenience,” supporting the conclusion that Gordon-Darby’s vendor relationship did not create a strong equitable basis to deny a stay; the termination risk was contractually foreseeable.
  • Am. Lung Ass'n v. Kean, 871 F.2d 319 (3d Cir. 1989) and Sierra Club v. Korleski, 681 F.3d 342 (6th Cir. 2012)
    Not decided, but flagged as an unresolved doctrinal conflict about whether and when the CAA authorizes citizen suits against state regulators “qua regulators.” The panel explicitly “express[es] no view” on this issue at the stay stage.

B. Legal Reasoning

1. The stay framework and standard of review

The court applies the Nken four-factor test as framed by Rhode Island v. Trump. It emphasizes that the first two factors are “the most critical” and notes that legal conclusions embedded in the stay analysis are reviewed de novo.

2. Why the court found a strong likelihood of success on the merits

The opinion’s likelihood-of-success analysis is tightly focused on the statutory gatekeeping language in 42 U.S.C. § 7604(a)(1): a citizen may sue a person “alleged to have violated (if there is evidence that the alleged violation has been repeated) or to be in violation of” an “emission standard or limitation.” The court identifies a fundamental problem: when the complaint was filed (December 8, 2025), New Hampshire had not yet ended the I/M program or terminated the contract—both were scheduled to occur on January 31, 2026.

3. Communications about repeal were likely not a cognizable SIP violation

The district court treated state communications (public messaging that inspections would no longer be required after January 31, 2026) as a violation, relying on 40 C.F.R. § 51.368(a). The First Circuit accepts the Commissioners’ argument that this regulation “only sets out a required component of a SIP” and does not itself regulate state communications in a way that creates an enforceable “emission standard or limitation” for purposes of § 7604(a)(1).

Critically, the court notes that Gordon-Darby did not identify “anything in the SIP itself” that the communications violated—underscoring a recurring enforcement principle in cooperative-federalism regimes: federal enforceability turns on what the SIP actually requires, not on generalized regulatory context.

4. Vendor contract termination was likely not a cognizable SIP violation

The district court also treated contract termination as a violation of 40 C.F.R. § 51.350(c), which requires a state with ozone nonattainment areas to “commit to fully implement and enforce” an I/M program until EPA approves a SIP revision showing the area can maintain standards without it.

The First Circuit’s reasoning is pragmatic and textual: even if § 51.350(c) requires continuation of the program absent an approved SIP revision, it does not require retention of a particular vendor. Therefore, terminating Gordon-Darby’s contract—without more—likely does not equal failure to “fully implement and enforce” the I/M program. The court also observes that Gordon-Darby did not develop an argument defending the district court’s theory on this point.

5. Purely prospective violations do not satisfy “to be in violation of”

The most consequential portion of the order is its treatment of whether § 7604(a)(1) allows a citizen suit based solely on an anticipated future SIP violation. The district court saw a “novel question” and read Gwaltney v. Chesapeake Bay Foundation as supportive. The First Circuit disagrees.

The panel reads Gwaltney as requiring allegations of continuous or intermittent violations anchored in past violations—“a reasonable likelihood that a past polluter will continue to pollute in the future”—and as rejecting suits where there is no ongoing violation at filing. It emphasizes that Gwaltney did not say that an entity “with a clean record of regulatory compliance” can be sued solely for anticipated future noncompliance.

The court then aligns that reading with its own precedent, Pawtuxet Cove Marina, Inc. v. Ciba-Geigy Corp., emphasizing that the relevant concept is a continuing likelihood of repeat violations, not the mere possibility of a first violation in the future. On this basis, the court holds the Commissioners made a strong showing that the district court erred by treating the anticipated January 31, 2026 lapse as enough to establish that the State was “in violation of” at the time the suit commenced.

6. Issues the court intentionally did not decide

Having found likely failure at the threshold “in violation” requirement, the court declines to reach several broader, potentially constitutional issues raised by the Commissioners, including:

  • Whether the CAA can be used to regulate states “in their sovereign legislative, procurement, or police power capacities.”
  • Whether citizen suits can be brought against state regulators “qua regulators,” noting tension between Am. Lung Ass'n v. Kean and Sierra Club v. Korleski.
  • Whether the SIP preempts the state repeal law (noting the argument was underdeveloped).
  • Commandeering concerns.
  • Whether plaintiff injury was redressable (the court notes the Commissioners’ argument did not grapple with the district court’s “lost opportunity to bid” theory).

C. Impact

  • Narrowing (or at least policing) the timing of CAA citizen suits: The order signals that, in the First Circuit, plaintiffs will face substantial obstacles if they sue before a SIP-related duty has actually been breached. The court’s reading of “to be in violation of” disfavors “anticipatory” citizen suits aimed at preventing an announced future noncompliance date, absent plausible allegations of ongoing or repeated violations at filing.
  • Disentangling SIP obligations from implementation choices: The decision suggests courts should distinguish between required outcomes (e.g., maintaining an I/M program as a SIP commitment) and discretionary means (e.g., which vendor administers it). This may limit attempts by private contractors to convert procurement disputes into CAA enforcement actions.
  • Strengthening state irreparable-harm arguments against injunctions that block statutes: By relying on Maryland v. King and New Motor Vehicle Bd. of Cal. v. Orrin W. Fox Co., the opinion reinforces that federal injunctions preventing a State from effectuating duly enacted laws weigh heavily in favor of a stay—especially when merits success is plausible.
  • Leaving major federalism questions open: Because the court resolves the stay on threshold statutory grounds, it postpones (and thus preserves for future litigation) the deeper questions about citizen suits against state regulators, SIP-versus-state-law conflicts, and anti-commandeering constraints in the CAA context.

IV. Complex Concepts Simplified

  • “Cooperative federalism” (CAA): EPA sets national air standards; states choose how to meet them via SIPs. Once EPA approves a SIP, parts of it effectively operate as federal law, but the architecture still preserves significant state choice and sequencing (including EPA oversight and sanction tools).
  • SIP (State Implementation Plan): A state-authored plan, approved by EPA, that lists enforceable measures the state will use to meet air-quality goals. Citizen suits generally must tie the alleged violation to a requirement that actually exists in the SIP (or otherwise qualifies as an “emission standard or limitation”).
  • I/M program: A vehicle inspection/maintenance regime aimed at reducing emissions from cars and trucks, sometimes required as part of ozone nonattainment planning.
  • CAA citizen suit under 42 U.S.C. § 7604(a)(1): A private enforcement mechanism allowing “any person” to sue alleged violators of certain CAA/SIP duties, but only within defined limits—including the requirement that the defendant has violated repeatedly or “is in violation of” at the time of suit.
  • “Purely prospective violation”: A violation that has not happened yet and is only expected to occur later (e.g., when a repeal law becomes effective). The First Circuit’s order indicates such a prediction, standing alone, likely does not satisfy “to be in violation of.”
  • Stay pending appeal: A temporary pause of a lower-court order while the appeal is decided. It is not a final decision on who ultimately wins, but it often provides a strong signal about the appellate court’s view of the merits and harms.
  • Termination “for convenience”: A contract clause allowing one party (often the government) to end the contract without proving breach. The court treats such a clause as weakening claims of unfair surprise or inequitable harm from termination.

V. Conclusion

The First Circuit’s stay order in Gordon-Darby Holdings, Inc. v. Quinn establishes an important, practical boundary for CAA citizen suits in the First Circuit: plaintiffs are unlikely to proceed where the alleged SIP noncompliance is only prospective at the time of filing, and where the asserted “violations” are not clearly tied to enforceable SIP requirements (as opposed to SIP-component regulations or discretionary implementation choices like vendor selection).

Equally significant, the court treats as gravely injurious an injunction that compels a State to continue enforcing a repealed program, making stays more likely in similar federalism-sensitive disputes. While the merits appeal remains pending, the order’s analysis provides a roadmap: successful CAA citizen-suit claims will need careful pleading and proof of an actual present violation (or repeated past violations creating a continuing likelihood), not merely an announced future policy change.