The U.S. Supreme Court on Monday (September 14, 2026) declined to let the U.S. Postal Service enforce a rule targeting mail-in ballots, dealing a setback to President Donald Trump's effort to restrict voting by mail ahead of November's midterm elections that will determine control of Congress.

The justices denied the Justice Department's request to lift a ruling by Boston-based U.S. District Judge Indira Talwani that blocked the Postal Service from enforcing the measure while legal challenges by states and voting-rights groups proceed. The agency adopted the measure after Trump issued a March executive order aimed at tightening rules governing mail voting.

The court said the government is unlikely to succeed on the merits of its challenge to the District Court's preliminary injunction.