Democratic‑led states sue USPS to block Trump‑backed mail‑voting rule after Supreme Court step

About two dozen Democratic‑led states on Wednesday filed a new lawsuit in federal court challenging a U.S. Postal Service rule that would enforce parts of President Donald Trump’s executive order tightening controls on mail‑in voting. The filing, brought by a coalition of state attorneys general, asks a judge to block the Postal Service from putting the rule into effect while litigation proceeds. The states say the rule upends long‑standing state control over ballot design and the administration of absentee and mail ballots.

The lawsuit follows a flurry of legal and administrative moves this week. On Aug. 24, 2026, the U.S. Supreme Court allowed the administration to proceed in a separate challenge on procedural grounds, saying the states had sued too early — but the high court did not rule that the order is lawful. In the days after that decision the Postal Service posted a final rule in the Federal Register laying out envelope design requirements, barcoded tracking and a mandate that states transmit lists of intended mail‑ballot recipients to a federal portal.

State lawyers say the Postal Service’s publication of a final rule changed the legal landscape and gave them concrete grounds to sue. The complaint argues the rule would displace state election laws, exceed the Postal Service’s statutory authority, violate the Privacy Act by creating and using a new voter database, and impose operational burdens that could disrupt preparations for the Nov. 3, 2026 midterm elections. New York Attorney General Letitia James, a lead filer, said the Postal Service “has no authority to decide who can and cannot vote by mail.”

The administration and the Postal Service have defended the policy as necessary to protect ballot security and to standardize mail‑ballot handling. The White House described the measures as “commonsense” steps to secure elections, and agency officials say the rule is meant to ensure ballots are trackable and reach intended recipients. The Postal Service declined detailed comment in light of pending litigation.

Legal experts and election officials warn the dispute raises practical questions beyond abstract constitutional claims. Many states have already printed ballots, trained staff and set mailing schedules; sudden federal changes to envelope formats or to the data states must send to the Postal Service could require costly rework or last‑minute voter notices. Plaintiffs say the rule's technical requirements — including unique barcodes and a federal submission portal — cannot be implemented quickly and would risk confusion or reduced mail‑ballot turnout.

The litigation is layered. A federal judge in Massachusetts had earlier issued an injunction blocking the Postal Service from implementing the order for the 2026 election, and plaintiffs in the new suit ask that court to enforce and extend that relief. The states also moved for a temporary restraining order and preliminary injunction to freeze the rule pending full review. Meanwhile, the Justice Department and the Postal Service are likely to press appeals and point to the Supreme Court’s recent move as clearing procedural obstacles to implementation.

The fast succession of filings and rulings has national political consequences: mail voting remains a heavily used method in many states and a focal point of partisan debate. Even if courts ultimately bar the Postal Service from enforcing the rule for 2026, the litigation could produce uncertainty that affects election administration, voter behavior and political messaging in the weeks before the midterms.