HARRISBURG, Pa. (AP) – The U.S. Supreme Court is invalidating a lower appeals court decision regarding how rules for mail-in ballots had been applied in a Pennsylvania election. The decision Tuesday adds an element of uncertainty about voting procedures four weeks ahead of the state’s high-stakes elections for governor and U.S. Senate. Pennsylvania’s top-ranking elections official says the decision is under review and that guidance to counties about how to handle such ballots will be updated if necessary. The justices vacated a decision in May by the 3rd U.S. Circuit Court of Appeals that had said mail-in ballots without a required date on the return envelope must be allowed in a 2021 Pennsylvania judge race.