States, civic groups urge Supreme Court to leave order in place prohibiting Trump administration from implementing parts of mail

California, joined by a group of 22 states and the District of Columbia, urged the Supreme Court on Wednesday to leave in place a ruling by a federal judge in Boston that prohibits the Trump administration from implementing parts of a U.S. Postal Service rule on mail-in ballots. Ian Fein, California’s deputy solicitor general, told the justices that “USPS’ unprecedented experiment with our Nation’s most cherished franchise—the right to vote—is unlawful.” The 40-page filing was the latest chapter in an ongoing battle over the Trump administration’s efforts to put restrictions on mail-in voting in place before the November elections. The dispute began nearly six months ago, when President Donald Trump signed an executive order that instructed federal agencies to take a series of steps on mail-in voting. The first provision orders the Department of Homeland Security to create lists of the adult U.S. citizens in each state and to send those lists to states at least 60 days before a federal election. The second provision directs the U.S. attorney general to “prioritize the investigation and, as appropriate, the prosecution of State and local officials … who issue Federal ballots to individuals not eligible to vote in a Federal election.” And the third provision requires states to provide the U.S. Postal Service with a list of voters to whom the states intend to send mail ballots, and it bars the Postal Service from mailing ballots to voters who are not on the lists of “enrolled” voters that the USPS will create. A group of 23 states, led by California, and the District of Columbia went to federal court in Massachusetts, where they challenged the government’s implementation of the order. They contended that the order clashes with provisions in the Constitution that give states the power to determine voter eligibility and to set the “Times, Places, and Manner” of holding congressional elections. In an order on June 25, U.S. District Judge Indira Talwani temporarily barred the federal government from implementing the challenged restrictions on or before the upcoming November elections in California, the states joining the lawsuit, or D.C. The U.S. Court of Appeals for the 1st Circuit declined to put that order on hold to give the government time to appeal. That prompted the Trump administration to come to the Supreme Court on July 27, where – along with a group of 12 states, led by Alabama, that had joined the case on the Trump administration’s side – it asked the justices to pause Talwani’s order. On Aug. 24, the Supreme Court cleared the way for the Trump administration to begin implementing the executive order. Over the objections of the court’s three Democratic appointees, the majority explained that the states’ challenge was premature because the order had not yet been carried out – and, as a result, the states had not suffered the kind of injury that would allow their lawsuit to proceed. Three days later, Talwani issued a new order: a temporary restraining order that barred the Trump administration, for 14 days, from requiring states to comply with several provisions of the new Postal Service rule, such as ballot envelope design requirements and the submission of voter data into a USPS portal. The Trump administration went back to the Supreme Court on Thursday, where U.S. Solicitor General D. John Sauer asked the justices to pause Talwani’s temporary restraining order (and to issue an administrative stay, an even more temporary form of relief that would put the order on hold while they considered the government’s request). Thursday’s request proved to be short-lived. The very next day, Talwani issued a preliminary injunction, which replaced her Aug. 27 temporary restraining order and prohibited the Trump administration from requiring states to comply with provisions of the rule indefinitely while the litigation moves forward. Sauer then submitted a letter to Scott Harris, the clerk of the Supreme Court, withdrawing the Trump administration’s second application for relief in light of Talwani’s new order. Telling the court that Talwani’s “continuing prejudgment of the rule is baseless,” and her rationale is “simplistic,” Sauer returned to the court for a third time on Sunday, asking the justices to pause the Sept. 4 preliminary injunction. Sauer rejected any suggestion “that the Postal Service is trying to federalize the rules for mail-in voting.” Instead, he insisted, “the Postal Service’s final rule imposes only modest envelope-design and addressee-information requirements for federal-election ballots sent via U.S. Mail.” Moreover, Sauer continued, the Postal Service’s new rule “is plainly constitutional. While the States have primary authority to regulate the manner of elections, they cannot choose to use the federal mails to carry out their elections but then insist that their election-related mail is somehow exempt from the Postal Service’s rulemaking authority, conferred by Congress, to regulate envelope design and addressee information.” If Talwani’s order is not put on hold, Sauer said, the government will – as the Supreme Court has already recognized in earlier proceedings involving the rule – suffer permanent harm (a key factor in determining whether to award temporary relief) because the election is so soon. North Carolina has already started to mail out ballots, Alabama will do so on Sept. 9, and “at least five States” will do so the following week – all without being required to comply with the new rule. By contrast, Sauer contended, the states’ claims that complying with the rule will harm them are “overblown.” In their response on Wednesday, California and the other states told the court that Talwani’s preliminary injunction should remain in effect, warning of dire consequences if the Postal Service is allowed to implement the rule now. “In some States,” Fein wrote, “unrebutted evidence establishes that compliance with USPS’ rule would be impossible ahead of the midterms, meaning that millions of voters would be unable to vote by mail and some would not be able to vote at all. In the remaining States, there would be chaos—and a significant risk that millions more voters would be denied the ability to vote.” Moreover, Fein added, “even if state and local officials were somehow able to implement the new rule perfectly, there is a high risk of technical breakdown, ineptitude, and delay on the part of USPS.” Fein pointed in particular to reports that a whistleblower has indicated that the USPS online portal for the submission of voter data has been created in a “sloppy and rushed manner.” Fein suggested that the Supreme Court should be “skeptic[al]” of USPS’ efforts to regulate elections given that it has never done so before, “[a]nd nothing in federal law authorizes USPS to refuse to deliver ballots.” To the contrary, Fein noted, to the extent that Congress has addressed voting by mail, it has done so “only by requiring USPS to make mail voting easier for States and voters.” A brief filed on Wednesday by the League of Women Voters and other civic groups, which had filed their own challenge to one part of the rule, also asked the court to leave Talwani’s order in place. Lawyer Sophia Lin Lakin of the ACLU, which represents the groups, told the justices that “Congress charged the Postal Service with delivering the mail nationwide, subject to a scheme of narrow exceptions for specified categories of material that Congress itself—not USPS—has deemed ‘nonmailable’ and subject to rules of general application such as sufficient postage. Mail ballots fall outside those congressionally prescribed exceptions.” Lakin added that, in contrast with the chaos that would result from pausing Talwani’s order now, “maintaining the injunction imposes no comparable harm on USPS, where the agency concedes that, despite its asserted interest in ‘election integrity,’ it has no role in verifying whether mail voters are eligible.” Recommended Citation: Amy Howe, States, civic groups urge Supreme Court to leave order in place prohibiting Trump administration from implementing parts of mail-in ballot rule, SCOTUSblog (Sep. 9, 2026, 4:43 PM), https://www.scotusblog.com/2026/09/states-civic-groups-urge-supreme-court-to-leave-order-in-place-prohibiting-trump-administration-/