"We find no restriction in our Constitution on the General Assembly's ability to create universal mail-in voting," wrote Justice Christine Donohue in the majority opinion.
The 5-2 ruling, with the two Republican justices, both voting no, means expanded vote-by-mail will likely be in place for marquee races in November for governor and U.S. Senate.
A lower court panel with a majority of Republican judges had dismissed the regulation in January, a judgment that was halted while the state Supreme Court examined an appeal by the administration of Democratic Gov. Tom Wolf.
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In the new finding, the justices corresponded with Wolf's claim that the lower court erroneously based its decision on court rulings that addressed older versions of the state constitution that had invalidated antiquated laws passed to expand absentee voting.
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The majority mentioned a provision of the Pennsylvania Constitution, "method of elections," that says all elections shall be by ballot "or by such other method as may be prescribed by law."
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Wolf's lawyers had told the court the current version of the state constitution should not be interpreted to outlaw voting by mail that goes beyond allowing it for people who are out of town on business, ill, physically disabled or performing election day duties or religious observance. They said the constitution sets only minimums for absentee and mail-in ballots.
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"Today’s court ruling definitively asserts that mail-in voting is a legal and constitutional method for Pennsylvania voters," Wolf said in a statement. "By upholding the law, which the General Assembly approved in 2019 in a bipartisan manner, 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."
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Fourteen Republican state lawmakers sued last month in another shot to get the mail-in voting law thrown out. That lawsuit hinges on a provision that says the law becomes null when any of its requirements are dismissed in court.
The awaiting lawsuit says the "non-severability" provision was triggered by a May 20 decision by a panel of the 3rd U.S. Circuit Court of Appeals over the law's requirement that mail-in ballots have a voter's handwritten date on the outside envelope. The federal appeals court panel found that a handwritten date had no bearing on a voter's eligibility in a Lehigh County judicial race last November.
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More than half of states now allow no-excuse absentee voting. Pennsylvania joined them in 2019, when Wolf agreed to a deal that also tossed the straight-ticket voting by party option on ballots. But many Republicans soured on the law after Trump claimed mail-in voting was rife with fraud.
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