The Supreme Court on Monday refused to allow the Trump administration to implement new mail-in ballot restrictions ahead of the November midterm elections, leaving in place a lower-court injunction that blocks the U.S. Postal Service from enforcing the rules.
The decision represents the latest turn in a fast-moving legal battle over President Donald Trump’s effort to change how mail ballots are handled nationwide. It is also a relatively rare loss for the administration on the Supreme Court’s emergency docket, where the justices have repeatedly intervened in disputes involving Trump administration policies.
In a brief unsigned order, the court concluded that the administration had not made the case for lifting the injunction while litigation continues.
“The Government is unlikely to succeed on the merits of its challenge to the District Court’s preliminary injunction,” the court said.
The court also concluded that the other factors considered when granting emergency relief did not favor putting the Postal Service rule into effect.
Justice Brett Kavanaugh, one of three justices appointed by Trump during his first term, wrote separately to explain why he agreed with the result.
Kavanaugh indicated that the Postal Service may ultimately have the legal authority to impose at least some of the requirements. But he said implementing the changes for the 2026 elections would violate federal administrative law because state and local election officials have too little time to make the necessary changes.
“But applying the rule in the 2026 elections would be arbitrary and capricious in violation of the Administrative Procedure Act because state and local election officials do not have sufficient time to reasonably implement the rule before the elections,” Kavanaugh wrote.
Justices Samuel Alito and Clarence Thomas dissented.
Alito questioned whether some of the plaintiffs had standing to bring their challenges and expressed skepticism about the legal claims advanced by the remaining challengers.
“Some of the plaintiffs lack standing, while the remainder are pursuing a claim that this Court has recently called a ‘Hail Mary pass’ that ‘rarely succeeds,’” Alito wrote in an opinion joined by Thomas.
No other justice publicly disclosed a vote in the case.
Postal Service Rules at Center of Fight
The dispute stems from an executive order Trump signed in March that directed changes to the handling of mail ballots. The administration has argued the measures are intended to strengthen election integrity.
The Postal Service subsequently developed a rule that would require states to provide information identifying voters receiving mail ballots and impose new requirements on ballot envelopes, including standardized design and technology requirements. Ballots that failed to comply could be rejected by the Postal Service.
The administration has maintained that the requirements fall within the Postal Service’s existing authority to establish rules for mail preparation and delivery.
Solicitor General D. John Sauer described the requirements as modest in a Supreme Court filing and argued that the Postal Service would not determine who is eligible to vote. Instead, states would continue making those decisions.
“Every day that the district court’s injunction remains in place, more ballots are being sent through the U.S. Mail without the benefits that the Rule provides for election integrity,” Sauer wrote.
Opponents contend the administration is attempting to exercise federal authority that belongs primarily to state and local election officials and that implementing the changes shortly before the election could prevent eligible voters from successfully casting mail ballots.
Trump has long argued that mail voting creates opportunities for significant election fraud. Documented voter fraud does occur, including isolated cases involving mail ballots, but evidence has not established fraud on the widespread scale Trump has alleged.
Case Has Repeatedly Reached Supreme Court
The litigation has taken an unusually complicated route to the Supreme Court.
U.S. District Judge Indira Talwani, an Obama appointee serving in Boston, has repeatedly blocked portions of the administration’s effort.
An earlier round of the dispute centered on Trump’s executive order itself. The Supreme Court intervened in August after concluding that the states challenging the policy were unlikely to have standing at that stage of the litigation.
The legal landscape changed after the Postal Service issued its final rule in August detailing how it intended to implement Trump’s directive.
Talwani then blocked that rule. The Justice Department returned to the Supreme Court seeking emergency relief, but the procedural posture changed again when Talwani replaced an earlier temporary order with a preliminary injunction. The administration then filed its latest request asking the justices to put that injunction on hold.
Monday’s decision leaves Talwani’s injunction intact and prevents the Postal Service requirements from taking effect for now.
The administration also encountered another setback Sunday when U.S. District Judge Carl Nichols, a Trump appointee in Washington, issued a preliminary injunction against the Postal Service rule in a separate lawsuit. Nichols concluded that the Postal Service lacked authority to enforce key portions of the policy.
That separate ruling was not the one before the Supreme Court on Monday.
Timing Looms Over Court's Decision
The rapidly approaching election appears to have played a major role in the Supreme Court’s decision, particularly for Kavanaugh.
Mail ballots are already being distributed in some states, leaving election administrators with limited time to redesign procedures, ballot envelopes and data systems before Election Day.
California Attorney General Rob Bonta, whose state is among those challenging the policy, praised the Supreme Court’s decision.
“Today’s decision is a victory for our democracy and a powerful affirmation of the rule of law,” Bonta said. “The stakes in this litigation could not have been higher. Voting is the fundamental right from which all other rights flow, and all 50 states allow ballots to be cast by mail in some form.”
Voting-rights organizations involved in the litigation also welcomed the ruling.
“Access to a free and fair election is critical to voter participation — and protecting access to mail ballots and the vote-by-mail process is crucial to ensuring voter participation, and most importantly, voter confidence,” said Celia Canavan, executive director of the League of Women Voters of Massachusetts.
“We will continue to press forward to ensure that every eligible voter is able to cast their ballot however they choose this election season — and have that vote counted,” she added.
The ruling does not necessarily settle the broader question of how much authority the Postal Service has to regulate election mail. Kavanaugh’s concurrence specifically left open the possibility that the rule could ultimately fall within the agency’s statutory authority.
