• The Supreme Court ruled 5-4 allowing states to count mail ballots received after Election Day.
• The ruling upholds Mississippi's grace period for counting mail-in ballots postmarked by Election Day.
• This decision represents a significant political defeat for the Trump administration.
• Justice Amy Coney Barrett wrote the majority opinion, supported by Chief Justice Roberts and three liberal justices.
• Over a dozen states, primarily Democratic-led, have similar laws permitting late ballot counts.

The U.S. Supreme Court has ruled that states may count mail ballots that arrive after Election Day, rejecting a Trump administration challenge against Mississippi's law which allows counting such ballots if they are postmarked by Election Day and arrive within five days afterward. The decision came as a 5-4 ruling that supports long-standing grace periods for mail-in ballots, aiming to ensure voter participation and account for postal delays, particularly highlighted during the pandemic, according to CBS News and Reuters.

This ruling not only affirms the Mississippi law but also affects similar regulations across 14 states, reinforcing the legitimacy of counting late mail ballots in the lead-up to critical midterm elections. The majority opinion, authored by Justice Amy Coney Barrett, asserted that while Election Day serves as a deadline for voters to cast their ballots, it does not dictate when those ballots must be received by election officials, which is a significant interpretation of federal election laws, according to NPR and Los Angeles Times.

The ruling is indicative of ongoing tensions surrounding mail-in voting, which has faced scrutiny from the Republican Party, particularly from former President Trump, who has disseminated unfounded claims about mail-in ballot fraud. The Court's decision represents a setback for the Republican National Committee (RNC), which pushed for stricter regulations arguing against grace periods, declaring that Election Day should also be the final day for ballot receipt, as stated in a legal brief presented by Trump's lawyers, according to BBC and Reuters.

This outcome has broader implications for state voting laws, particularly as it reinforces existing provisions in California and other Democratic-controlled states, enabling them to count late mail-in ballots. Experts have noted that these grace periods are critical for accommodating unforeseen delays in mail delivery, ensuring that even voters who may experience postal issues still have their voices heard, according to Los Angeles Times and NPR.