HARRISBURG — The state Supreme Court has upheld Pennsylvania’s mail ballot law, preserving for the time being a popular voting method that passed the legislature with bipartisan support but was later challenged by Republican elected officials.

In a 5-2 decision released Tuesday, the justices rejected the GOP argument that the legislature did not have the power under the state constitution to allow Pennsylvanians to vote by mail without an excuse.

The 2019 law, known as Act 77 and employed for the first time during the contentious 2020 presidential election, ushered in the most sweeping expansion of voting access in Pennsylvania in decades.

Republican elected officials who brought the suit said Tuesday that they plan to appeal to the U.S. Supreme Court. A handful of GOP state lawmakers are also pursuing another legal avenue to have the entire law thrown out.

The timeline to resolve the additional legal challenges is unclear, but supporters of the law said Tuesday’s ruling will preserve voters’ options ahead of the critical midterm election.

“This ruling assures that mail-in voting remains in place and Pennsylvanians will be able to cast their ballot legally in person or by mail without any disruption or confusion,” Gov. Tom Wolf, a Democrat who signed Act 77 into law, said in a statement.

In fall 2021, a county commissioner and 14 state House Republicans — 11 of whom voted for the law in 2019 — filed separate suits claiming Act 77 was unconstitutionally implemented as a statute. They argued that permitting no-excuse mail voting required amending the state constitution, a lengthy process in which voters decide the matter through a ballot question.

That argument was first used in an unsuccessful 2020 lawsuit brought by U.S. Rep. Mike Kelly, R-16th, that attempted to toss out 2.6 million votes cast by mail, likely handing the state’s 20 electoral votes to former President Donald Trump.

A lower appellate court earlier this year ruled in favor of the GOP officials, saying that permitting no-excuse mail voting through a statutory change violated the state constitution and court precedent dating back to the 1920s.

But in Tuesday’s majority opinion for the state Supreme Court, Justice Christine Donohue wrote that the Pennsylvania General Assembly “is endowed with great legislative power, subject only to express restrictions in the Constitution.”

While the expansion of voting rights is not guaranteed to be permanent, the legislature made a lawful policy decision, “based on the authority afforded it by our Charter, to afford all qualified voters the convenience of casting their votes by mail,” Donohue wrote.

All five of the justices who upheld Act 77 were elected as Democrats. Both of the dissenting justices were elected as Republicans.

Before Act 77′s passage in 2019, Pennsylvania had one of the most restrictive absentee ballot laws in the country.

That year, Wolf and the Republican General Assembly struck a deal to allow 50 days of no-excuse mail voting before each election in exchange for eliminating straight-ticket voting. All but two GOP lawmakers voted for the bill.

Despite the early support, Republican sentiment on the law shifted throughout the 2020 election cycle as Trump played up baseless fears of widespread fraud via mail voting, claims his allies repeated in Pennsylvania.

The Pennsylvania Department of State, which oversees voting, said Tuesday’s decision “assures eligible Pennsylvanians can vote by mail-in ballot in the Nov. 8 general election.”

But ongoing Republican challenges to the law — and a critical gubernatorial election later this year — mean there’s still some uncertainty about the future of mail voting.

State Rep. Tim Bonner, R-8th, one of the lawmakers who brought the suit, told Spotlight PA that the petitioners plan to appeal their case to the U.S. Supreme Court.

He also pointed to a separate, ongoing case that seeks to toss Act 77 over a legal technicality known as a “non-severability” clause.

Such a clause states that if “any provision of this act or its application to any person or circumstance is held invalid, the remaining provisions or applications of this act are void.”

In a suit filed this July in Commonwealth Court, Bonner and other GOP elected officials argued that a recent federal ruling has triggered that provision.

As written, Act 77 requires voters to “fill out, date and sign the declaration printed” on the outer mail ballot envelope. But in response to a challenge brought by a Lehigh County candidate, a federal judge found the requirement to be “immaterial” and in violation of federal voting rights law, and ordered election officials to count undated mail ballots. The U.S. Supreme Court declined to block that ruling.

State Supreme Court Justice Kevin Brobson, elected as a Republican, called the non-severability argument “an interesting question” in a six-page dissent to Tuesday’s ruling. It was unaddressed in the majority opinion.

In a July letter, the Department of State said the federal decision targeted county policy rather than state law and therefore Act 77 remained intact.

Outside of the courts, there is support among some Republicans in the legislature to completely repeal Act 77, with lawmakers in the state House and Senate — such as state Sen. Doug Mastriano, a Republican from Franklin, his party’s gubernatorial nominee — introducing legislation to do just that.

But so far, leadership has not brought these proposals up for a vote, and the measures also would face a guaranteed veto from Wolf.

In statements on Tuesday, GOP legislative leaders argued for election law changes but did not commit to advancing legislation that would repeal mail voting.

State Senate Republican spokesperson Erica Clayton Wright said that the ruling “underscores the importance of the actions taken by the General Assembly to strengthen election integrity.”

She pointed to a ban on third-party grants for election administration, signed by Wolf, and pending constitutional amendments that would implement universal voter ID and additional post-election audits.

Since 2020, legislative Republicans have attempted to make changes to Pennsylvania’s election law while keeping mail voting intact. The legislature last year passed an omnibus proposal from state Rep. Seth Grove, a Republican from York, that would have created early voting, instituted new security rules for drop boxes, and allowed voters to fix mail ballots with missing signatures.

Wolf vetoed the bill because of its stricter voter ID requirements, among other reasons.

In a statement, Grove, who is the chairman of the House committee charged with election administration, called Tuesday’s ruling unsurprising given the court’s partisan makeup and argued that the state needs to update its election law but did not say how.

Grove has reintroduced his election omnibus bill, but it has not advanced because of a lack of GOP support. Some rank-and-file Republicans, including Bonner, previously said they would not vote in favor of legislation that keeps mail voting intact until the high court ruled on their challenge.

As with many other policies, what happens next may all come down to the November gubernatorial election. Wolf is term-limited from running for office again.

Democratic nominee Josh Shapiro, the state’s attorney general, supports mail voting and has said he’d veto legislation restricting voting rights. Mastriano, who voted for Act 77 as a first-year lawmaker, has spoken out against mail ballots and spread false claims about them.

There’s also another route to eliminating mail voting that bypasses the governor — no matter who they are — completely.

Bonner said he supports sending a proposed constitutional amendment to the voters to repeal Act 77 and explicitly require that any future expansion of mail voting occur through the amendment process

“I think it would be best that the people will be given an opportunity to vote on what they want as an election process of Pennsylvania,” Bonner said.

Such amendments have become a popular route in recent years for Republicans to avoid Wolf and advance their policy priorities. These proposals must pass the General Assembly during two consecutive two-year sessions before going before voters for consideration.

They rarely fail to pass.

Spotlight PA is an independent, nonpartisan newsroom powered by The Philadelphia Inquirer in partnership with PennLive/The Patriot-News, TribLIVE/Pittsburgh Tribune-Review, and WITF Public Media.