The Supreme Court said Tuesday it won’t hear civil rights groups’ appeal seeking to invalidate Pennsylvania’s dating requirement for mail ballots, which has invalidated thousands of votes each recent election and become a central legal fight over voting in the key swing state.

The Pennsylvania State Conference of the NAACP, the American Civil Liberties Union (ACLU) and other organizations claimed the requirement violates the Civil Rights Act of 1964, which prohibits states from denying the right to vote because of an immaterial error. Republicans have sought to enforce the dating requirement. 

The Supreme Court turned away the groups’ appeal without comment, but it comes after Pennsylvania’s top court on Friday announced it would hear a separate lawsuit against the dating requirement. 

That lawsuit, which also involves the ACLU, challenges the requirement as violating the Pennsylvania Constitution’s Free and Equal Elections Clause. 

In 2019, Pennsylvania enacted no-excuse mail voting under Act 77, which also established technical requirements like returning the mail ballot envelope with the correct date. 

For years, the ACLU and other groups have filed extensive litigation seeking to allow the thousands of individuals who timely return their ballots with a missing or improper date to still have their vote counted.  

The battle again whiplashed through the courts in advance of the recent presidential election, when President Trump flipped Pennsylvania four years after former President Biden won it. 

In the lead-up to November’s contest, Pennsylvania’s top court repeatedly ordered the date requirement be enforced. It later chastised local Democratic officials who attempted to defy the court’s ruling by counting the challenged ballots. 

Civil rights groups have mounted multiple arguments against the dating requirement but broadly insist it is meaningless because election officials timestamp mail ballots when they are received.  

“All agree these voters are qualified, that they filled out and returned their ballots on time, and that the handwritten date has nothing to do with confirming voters’ identities or qualifications, determining timeliness, or preventing fraud. In other words, all agree the error is immaterial,” the ACLU wrote in its high court petition. 

The ACLU also told the justices that the Pennsylvania’s top court’s consideration of the other lawsuit could “result in binding statewide precedent that effectively resolves the issue in this litigation.” The justices should hold the petition or send it back to a lower court until the other case is resolved, the ACLU argued.  

The Republican National Committee told the justices to let the lower ruling stand, which found the dating requirement does not violate the Civil Rights Act of 1964 because its materiality provision applies only to registration forms, not actual ballots. 

“Petitioners again challenge the date requirement but can invoke zero appellate precedent supporting, much less adopting, their reading of the Provision. No surprise, then, that Petitioners do not identify any split in appellate authority. That is reason enough to deny their petition and, at a minimum, allow the question presented to percolate in the lower courts before taking it up,” the RNC wrote in court filings.