US Supreme Court to hear case that could redefine mail-in voting rules

At issue in the case is a Mississippi law allowing mail-in ballots postmarked by Election Day to be counted if they arrive within five business days. Plaintiffs from Donald Trump’s Republican Party argue the policy violates federal law, which requires that presidential elections conclude on Election Day. Trump has waged a long campaign against mail-in voting, fearing that allowing more time to vote favors the Democratic Party, though it is a popular voting method in many US states.

In October 2024, the 5th US Circuit Court of Appeals invalidated the law in the Southern state, ruling that all mail-in ballots must be both sent and received by Election Day to comply with federal standards. The court said the process must reach “finality” on that date, not extend while ballots continue arriving.

Five judges dissented from the decision, warning that it “runs counter to traditional tools of statutory interpretation” and threatens similar voting provisions in at least 28 states.

Michael Watson, secretary of state in Mississippi, argues that the term “election” refers only to the act of casting ballots, not the administrative counting process.

The justices are expected to hear arguments next spring. The outcome could redefine the balance of federal and state authority over ballot deadlines, a dispute that has intensified since the 2020 pandemic-driven surge in mail-in voting.

It could also tip the balance in next year’s midterm congressional elections, with one-third of the Senate and all members of the House of Representatives at stake. With both houses of Congress now controlled by Republicans, Democrats are hoping to get enough anti-Trump voters to capture at least one house and complicate the rest of Trump’s four-year term.

Restrictions on voting, however, could make the Democrats’ goal more difficult.

Republicans claim mail-in voting is rife with fraud, but have produced little evidence to back this argument. Democrats say opposition to mail-in voting is part of longstanding efforts by Republicans to suppress voter turnout, especially for minorities.