The US Supreme Court denied the Trump administration’s request to immediately enforce new U.S. Postal Service requirements for federal election ballot mail ahead of the 2026 midterm elections.

The court rejected the government’s application to stay a lower court’s nationwide preliminary injunction blocking the rule on Monday.

Supreme Court Blocks USPS Ballot Rules

The disputed rule requires federal ballot mail to include an election-mail logo, be compatible with high-speed scanning equipment, and carry a voter-specific barcode. States would also have to submit envelope designs for USPS review and provide basic voter information through a Postal Service portal.

"The Government is unlikely to succeed on the merits of its challenge to the District Court’s preliminary injunction," the Supreme Court said.

Justice Brett Kavanaugh agreed with the decision but noted that USPS may have statutory authority to issue the rule. However, he stated that applying it during the 2026 elections would be "arbitrary and capricious" because state and local election officials lacked enough time to implement it.

Justices Samuel Alito and Clarence Thomas dissented. Alito argued that USPS has broad authority to regulate mail and said the government had made the necessary showing for the stay. He described the states’ challenge as "essentially a Hail Mary pass" that "rarely succeeds."

Trump Tightened Mail Voting Rules

In March, Trump signed an executive order to tighten mail-in voting rules, including using federal data to verify voter eligibility and requiring absentee ballots to be sent only to voters on approved state lists. The order also mandated secure ballot envelopes with unique tracking barcodes and drew immediate legal challenges from voting-rights groups and Democrats.

Last month, USPS unveiled mail-in voting rules based on Trump’s blocked March executive order. The rules would have required states to provide citizenship-based voter lists before USPS could send ballots.

U.S. District Judge Indira Talwani later blocked key parts of the overhaul nationwide, ruling that the executive branch lacked authority to regulate elections. She said states had primary authority over congressional election procedures and that Congress, not the president, could override those rules.

The Supreme Court ruled 6-3 to invalidate President Donald Trump’s executive order seeking to end birthright citizenship, reaffirming that everyone born on U.S. soil is automatically a citizen. Following the decision, the Justice Department instructed federal prosecutors to prioritize criminal investigations into alleged birth tourism schemes. In a memo issued Wednesday, the Justice Department’s Office of the Deputy Attorney General directed attorneys in its criminal division to make the investigation and prosecution of these schemes a priority.

DOJ Shifts Focus to Fraud

Colin McDonald, who leads the department’s fraud division, said prosecutors should aggressively pursue cases involving individuals or organizations accused of exploiting the U.S. immigration system through fraud. “The Department of Justice will zealously protect the sanctity of United States citizenship by investigating and prosecuting those who fraudulently exploit our immigration system,” McDonald wrote in the memo. The guidance encourages prosecutors to consider charges beyond immigration-related offenses, including wire fraud and money laundering, where appropriate.

Supreme Court Decision

Writing for the majority, Chief Justice John Roberts rejected the legal basis for Trump’s executive order. The decision triggered sharply divided reactions from lawmakers. Sen. Ted Cruz (R-Texas) called the ruling a “travesty,” arguing that the 14th Amendment was intended to guarantee citizenship for formerly enslaved people, not for children born to people in the U.S. illegally or temporarily. Conversely, Sen. Elizabeth Warren (D-Mass.) celebrated the decision, emphasizing that the Constitution clearly protects birthright citizenship.

Legislative Response and Statistics

Trump responded to the ruling by urging Congress to pass legislation to end what he called an “expensive and unfair” policy, pledging his “Complete and Total Support” for the effort. While birth tourism itself is not automatically illegal, authorities can prosecute individuals who allegedly obtain visas through deception or engage in related financial crimes. The Migration Policy Institute estimates that up to 26,000 births annually could be linked to birth tourism out of more than 3.5 million births in the U.S.