The Supreme Court sided Monday with the Trump administration in a challenge to President Donald Trump’s executive order restricting mail-in voting, but the conservative majority did not determine whether the order is lawful. Instead, the justices ruled that the states that sued lacked the legal right to bring the challenge. The unsigned order leaves room for further lawsuits, which could delay implementation before the approaching midterm elections. Trump’s March order directs the administration to create lists of eligible voters and instructs the U.S. Postal Service to deliver mail ballots only to people on those lists. Democratic officials in 23 states and the District of Columbia argued that the Constitution gives states and Congress authority over elections and warned that the changes could cause chaos and partisan abuse. Courts in Massachusetts had blocked the order for the midterms and later nationwide, while a separate Washington ruling allowed it to proceed. The Justice Department sought emergency relief, arguing the states sued too early. A dozen Republican-leaning states supported the federal government. The ruling came after the Supreme Court in June rejected a Trump-backed argument on mail ballots, finding that states can count ballots arriving after Election Day. Mail ballots accounted for about 30% of all votes cast in the 2024 presidential election, and a 2025 Brookings Institution study found about four fraud cases per 10 million mail ballots.