The Supreme Court of the United States has refused, by 7-2, to stay a lower-court injunction blocking the Supreme Court USPS mail ballot rule that federal judges found would risk disenfranchising millions of voters ahead of the November midterms. The order in United States Postal Service, et al. v. California, et al., docket number 26A305, leaves the preliminary injunction in place for all elections on or before 3 November 2026.
The application for a stay was first presented to Justice Ketanji Brown Jackson, who referred it to the full Court. The majority offered little formal analysis but stated plainly that ‘the Government is unlikely to succeed on the merits of its challenge to the District Court’s preliminary injunction.’
What the Supreme Court USPS Mail Ballot Ruling Actually Decided
The rule at issue, titled ‘Ballot Mail for Federal Elections,’ was published at 91 Fed. Reg. 54966 (26 August 2026) and is to be codified at 39 C.F.R. pt. 111. It implemented Executive Order No. 14399, titled ‘Ensuring Citizenship Verification and Integrity in Federal Elections,’ issued on 31 March 2026 and published at 91 Fed. Reg. 17125.
The rule required states to follow specific envelope-design guidelines for mail ballots, generate unique barcodes for every ballot, and upload advance voter lists to a new federal portal that was not yet operational at the time the injunction was granted. A whistleblower report filed with the district court warned of ‘potentially catastrophic problems’ with implementation, characterising the administration’s efforts as ‘sloppy and rushed,’ according to the California Attorney General’s office.
U.S. District Judge Indira Talwani of the District of Massachusetts had entered a temporary restraining order on 27 August 2026, followed by a full preliminary injunction on 4 September 2026 after a hearing the previous day. The League of Women Voters of Massachusetts led the coalition of co-plaintiffs in that district court proceeding, as Courthouse News Service reported.
The Concurrence, the Dissent, and the Statutory Battleground
Justice Brett Kavanaugh concurred in the denial, writing that he sees ‘at least a fair prospect that the final rule falls within the Postal Service’s statutory authority’ under 39 U.S.C. §3001(m). He nevertheless agreed the district court was right to block it under 5 U.S.C. §706(2)(A) of the Administrative Procedure Act, because state and local election officials lacked sufficient time to implement the rule before the elections.
The implementation problem was concrete. Massachusetts alone had already spent $3 million on mail-in ballot envelopes by April 2026 that would not comply with the new requirements, the First Circuit’s nine-page opinion noted.
Justice Samuel Alito dissented, joined by Justice Clarence Thomas. Alito argued the rule fell within the USPS’s existing statutory authority to make rules for the collection and delivery of mail, and characterised the plaintiffs’ legal theory as a ‘Hail Mary pass’ that ‘rarely succeeds,’ citing NRC v. Texas, 605 U.S. 665, 681-682 (2025). He also argued that some plaintiffs lacked standing.
The majority view, and the reasoning of the courts below, is that inferring a sweeping power to rewrite state mail-in voting rules from a general grant of authority over mail delivery is precisely the kind of statutory overreach that the major questions doctrine is designed to prevent. As the district court found, Congress must speak clearly when delegating a ‘highly consequential power’ to the executive branch, and statutes authorising the USPS to regulate mail collection and delivery do not mention voting rules at all.
The First Circuit panel, comprising Judges Gustavo A. Gelpí, Julie Rikelman, and Seth Aframe, concluded in its own ruling that implementing the USPS rule would ‘likely result in the disenfranchisement of millions of voters across the country while providing minimal (if any) gains in combating voter fraud,’ according to CBS News.
The ACLU, which was among those challenging the rule, noted that the federal portal states were required to use had not even been made operational by the time the injunction proceedings concluded, as the ACLU’s press release set out in detail.
The Supreme Court’s 14 September 2026 ruling follows an earlier and distinct order. On 24 August 2026, in Trump v. California, No. 26A124, the Court had granted a stay of an injunction against the executive order itself, on justiciability and ripeness grounds, before the final USPS rule had even been issued. That earlier stay did not address the rule’s merits, leaving the legal questions to be fought out once the rule was finalised, as the American Society of International Law observed.
The preliminary injunction blocks only the mandatory provisions of the Final Rule for elections on or before 3 November 2026. The rule remains operative for elections after that date, and litigation on the full merits continues. Subject to any onward appeal, the next decisive moment will be whether the government can prevail at trial on the statutory and constitutional questions the courts have so far found it unlikely to win.
