Updated November 01, 2024 at 19:15 PM ET

With voting underway for Pennsylvania’s general election, legal questions about the ballots of mail-in voters have been looming in the swing state that could determine the winner of the presidential race.

From what have become known as “undated ballots” to so-called “naked ballots,” the range of issues before state and federal courts center on what to do when voters return absentee ballots on time but don’t follow all of the rules for getting their votes counted.

State law requires completed mail-in ballots to be sent back in two envelopes — an inner secrecy envelope and an outer envelope. On that return envelope, voters have to add their signatures and the current date.

Election officials do not use that handwritten date to verify that a ballot was received by the legal deadline, but thousands of voters in recent elections have had ballots arrive on time but ultimately tossed for failure to properly date their outer envelopes.

Under state law, voters whose mail-in ballots are rejected can vote with a provisional ballot at a polling place.

Republican groups contend that the ballots of voters who have not followed the rules should not be counted, while voting rights groups have been arguing that state and federal laws protect eligible Pennsylvanians’ votes from getting disenfranchised because of a mistake.

In recent elections, Democrats have outnumbered Republicans in casting mail-in ballots, a method of voting that was opened to all registered voters in Pennsylvania in 2019 with bipartisan support at the time from the state’s lawmakers.

The state legislature’s bipartisan advisory board on election law has since recommended changing Pennsylvania’s rules. To “eliminate confusion and litigation” about mail-in ballots, the board wrote in a report last year, it called for rewriting state laws to say that not using a secrecy envelope or not having a handwritten date on the outer envelope would not disqualify a ballot.

But partisan gridlock has curtailed efforts to revise voting laws.

In the meantime, state officials have redesigned the envelopes to try to help voters identify the yellow secrecy envelopes and remember the date requirement.

And as the last day of voting draws closer, judges face a tight timeline for trying to resolve these lawsuits so that election offices have clear instructions on what to do with the ballots they receive. Officials are already under pressure from a state law that bans them from processing mail-in ballots until 7 a.m. ET on Election Day, potentially delaying the reporting of results.

Here’s where the major legal questions about Pennsylvania’s mail-in ballots stand:

Should “undated” and misdated ballots be counted?

No, the Pennsylvania Supreme Court ruled Friday.

The state’s high court confirmed that a recent narrow ruling by a lower court should not be applied to this fall’s election. Released on Wednesday, that lower court ruling found that not tallying these types of ballots in a September special election in Philadelphia violates the state’s constitution.

As requested by the Republican National Committee, the high court paused the lower court decision, which came out of a lawsuit filed on behalf of two registered Philadelphia voters whose ballots for the special election were missing handwritten dates.

Responding to that lower court ruling, Pennsylvania’s Department of State, which oversees elections, said it was pleased that it enfranchised voters in that special election and wouldn’t interfere with this fall’s general election.

For this election, there could be tens of thousands of ballots arriving on time but missing the current date handwritten by absentee voters, the American Civil Liberties Union of Pennsylvania and the Public Interest Law Center estimate.

And that could lead to another legal challenge after Election Day.

Leading up to Nov. 5, this issue has been getting a lot of attention in Pennsylvania’s courts. In September, the Pennsylvania Supreme Court cited procedural issues and threw out an earlier lower court ruling that had found not counting mail-in ballots in return envelopes without any handwritten date or with an incorrect one violates Pennsylvania’s constitution, which says that all elections in the state must be free and equal.

And the high court declined to hear another case on the issue, saying in an unsigned order that while it will continue to review lower court decisions, it “will neither impose nor countenance substantial alterations to existing laws and procedures during the pendency of an ongoing election.”

And there are similar legal fights in the federal courts that may affect what ultimately happens to these ballots. Civil rights groups represented by the ACLU formally asked the U.S. Supreme Court in September to review whether not counting these ballots violates the Civil Rights Act of 1964, which says a person's right to vote cannot be denied for "an error or omission on any record or paper relating to any application, registration, or other act requisite to voting" that is "not material" in determining whether they’re qualified to vote. Until the Supreme Court decides whether to step in, a lower federal court is waiting to weigh in on an argument that excluding these ballots goes against the U.S. Constitution.

Should the provisional ballots of voters who return “naked ballots” be counted?

Yes, the Pennsylvania Supreme Court ruled this month.

The state’s high court upheld a lower court ruling that found that election officials in Pennsylvania’s Butler County, just north of Pittsburgh, should count the provisional ballots of two “naked ballot” voters, who cast them for this year’s primary election after officials notified them that their returned mail-in ballots were rejected for lacking secrecy envelopes.

In their appeal to the Pennsylvania Supreme Court, the Republican National Committee and the Republican Party of Pennsylvania argued that counties contacting voters with defective mail-in ballots and allowing them to cast provisional ballots amounts to what’s known as a “notice and opportunity to cure” procedure, a process that’s separate from provisional voting. Counties in the state can choose to put in place notice-and-cure policies but, according to a 2020 Pennsylvania Supreme Court ruling in a different case, state courts are not allowed to order them.

In its new ruling, the state’s high court rejected the Republicans’ argument. “As the Commonwealth Court aptly observed, no ballot is cured when a provisional ballot is counted after a mail ballot is rejected due to a fatal defect in the Return Packet,” the court’s majority opinion said.

This week, both the Pennsylvania Supreme Court and the U.S. Supreme Court denied the GOP groups’ request to pause the state court’s ruling.

In a separate but related court petition to the Pennsylvania Supreme Court, the GOP groups argue that counties across the state have “adopted a patchwork of notice-and-cure policies” and as a result, not uniformly carried out the state’s election rules, in violation of both the state and U.S. constitutions. But the state’s high court declined to take up that petition.

Are county election officials required to inform voters of errors that get their mail-in ballots thrown out?

Yes, in Pennsylvania’s Washington County, just south of Pittsburgh, the Commonwealth Court ruled in September.

The state court found that the county’s policy of not informing voters of mail-in ballot errors — such as missing a signature or the current date handwritten on the return envelope — “emasculates” guarantees under Pennsylvania’s election law by taking away the chance for voters to cast provisional ballots.

But the Pennsylvania Supreme Court is now reviewing the case after the RNC and the state’s Republican Party appealed. If the state’s high court upholds the lower court’s decision, court watchers expect all counties in the swing state would be required to give mail-in voters notice if their returned ballots have errors that would get them thrown out.

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