The Supreme Court said late Monday that a U.S. Postal Service rule to restrict mail-in voting cannot go into effect for the midterm elections. The rule would have required states to submit voter lists to the Postal Service to determine who is eligible to receive a mail ballot. With the decision, Colorado will be allowed to mail a ballot to all registered voters as required under state law.
The Supreme Court justices said in an opinion Monday night that the government is “unlikely to succeed on the merits of its challenge.”
Justice Brett Kavanaugh said there is at least a fair prospect that the final rule falls within the Postal Service’s statutory authority but the order applying the rule to the 2026 elections would be “arbitrary and capricious,” and that it would not give local election officials time to implement the rule before the election.
The order was unsigned and it was not accompanied by a vote count. Justices Samuel Alito and Clarence Thomas filed a dissent to the order.
Colorado Secretary of State Jena Griswold said in a statement that the decision is a major victory for Colorado and American democracy.
“Trump’s attempt to sabotage the 2026 elections has failed. Courts have blocked Trump from using the Postal Service to choose which voters could receive a mail ballot. Trump will continue to fail in his efforts to take control of the 2026 midterms,” Griswold said.
Colorado is among the eight states that mails a ballot to every voter, according to the National Conference of State Legislatures, and state officials said the Postal Service rule would be difficult to implement this close to the election.
“There has been no engagement with the election community. There have not been hearings, open and transparent hearings to hear from people of all sides about the policy,” said Matt Crane, the head of the Colorado County Clerks Association.
The rule is part of President Donald Trump’s executive order last February to put guardrails on mail voting, which Trump said was necessary to strengthen and secure elections and reduce voter fraud.
Two-dozen states, including Colorado, filed a lawsuit to block the executive order from taking effect arguing that it unconstitutionally infringes on the right of states to conduct elections.
“The Constitution is clear that States have the primary responsibility for regulating and administering elections, subject only to preemption by Congress — authority that expressly extends to the ‘manner’ of elections,” said the lawsuit from the states.
The plaintiffs also argue that the Final Rule violates both the separation of powers doctrine and the USPS’s governing statutes. The rule requires the Postal Service to sign off on ballot envelope designs and require a specific type of bar code or ballots won’t be mailed.
The states said they are required under law to mail millions of ballots to voters on a set timeframe and are unable to pivot this late in the election cycle. National studies have indicated that instances of mail ballot voter fraud are incredibly rare. A Brookings Institution study found four cases out of every 10 million mail votes cast across U.S. general elections from 2016 to 2022.
In September, a federal judge in Massachusetts stopped the USPS from taking further steps to regulate mail ballots, which led to Trump’s appeal to the U.S Supreme Court.
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