The Supreme Court on Monday examined the constitutionality of a Mississippi law that allows mail-in ballots postmarked by Election Day to be counted if they arrive up to five business days later.

The case centers on whether such grace periods for ballot receipt comply with federal election law. Mississippi's statute permits ballots that bear an Election Day postmark to be counted even when received after polls close, provided they arrive within the specified timeframe.

More than a dozen states currently have similar provisions that extend the deadline for receiving mail-in ballots beyond Election Day, as long as the ballots were postmarked by the voting deadline. These laws were implemented to account for postal delivery delays and ensure that timely-submitted ballots are not disenfranchised due to mail processing times.

States with such grace period laws are monitoring the Supreme Court proceedings as they prepare contingency plans for potential changes to their ballot-counting procedures. A ruling against Mississippi's law could require these states to modify their election processes.

The outcome could have implications for future elections, including upcoming midterms, as states would need to adjust their vote-counting timelines and procedures if the Court determines that ballots must be physically received by Election Day to be valid.

The Court has not indicated when it will issue a decision on the matter.