Key court decision allows extension of absentee ballot deadlines in swing states of Pennsylvania and North CarolinaThe US supreme court has rejected a last-minute plea from Pennsylvania Republicans to overturn a three-day extension of the absentee ballot deadline, a hugely consequential ruling in one of the most closely watched swing states in the presidential election.The state usually requires ballots to arrive by 8pm on election night in order to count. But last month, the Pennsylvania supreme court extended that deadline by three days for ballots postmarked by election day, a move likely to allow thousands of late-arriving ballots to count.Pennsylvania Republicans asked the US supreme court to halt that ruling pending appeal, but it declined to do so last week, deadlocking 4-4 and offering no explanation for its decision. The Pennsylvania Republican party then asked the court to expedite the case, which the court again declined to do on Wednesday.Wednesday’s decision is the latest in a series on important rulings on absentee ballots in key swing states. Shortly after Pennsylvania, the supreme court also declined to block an agreement giving North Carolina voters more time to return their absentee ballots.Despite Wednesday’s ruling on Pennsylvania, three of the court’s conservative justices – Samuel Alito, Neil Gorsuch, and Clarence Thomas – signaled the court might still consider the case after the election. The Pennsylvania supreme court’s ruling “likely violates the federal constitution”, Alito wrote for the three, and its decision “could lead to serious post-election problems”.Prior to the court’s decision, Pennsylvania’s top election official instructed counties to segregate ballots that arrived after 8pm on election day from ones that arrived before. The move appeared to be an attempt to ensure any future court ruling could target just the late-arriving ballots without affecting those that made the deadline.“This was a careful decision designed to ensure all eligible Pennsylvania votes will be counted and to stave off anticipated legal challenges from Donald Trump and his enablers,” the state attorney general, Josh Shapiro, told the court, according to the Wall Street Journal.North Carolina state law allows voters to return ballots up to three days after elections, as long as they are postmarked by election day. But earlier, the North Carolina state board of elections, the top elections body in the state, agreed to extend that deadline until 12 November, in an effort to settle a lawsuit. North Carolina Republicans, who control the state legislature, challenged that extension and asked the supreme court to overturn it.Earlier this week, the court stepped in and blocked a six day extension of the ballot receipt deadline in Wisconsin. Both the North Carolina and Pennsylvania cases, where the court declined to intervene, involved disputes over state law tied up in state courts. In Wisconsin, where the court did intervene, the case was limited to the federal court.In the Pennsylvania ruling, the three conservative justices also voiced support for the view that state supreme courts have limited authority to second-guess legislatures on rules for federal elections, a view Justice Brett Kavanaugh voiced on Monday. That view could come into play in post-election disputes in states like North Carolina and Pennsylvania – which have Republican-controlled legislatures but Democratic majorities on the supreme court. In the future, the lack of oversight from state courts could give state lawmakers far more leeway to pass laws that make it harder to vote.The court offered no explanation for its decision in North Carolina case, which is not unusual for cases such as this, which come before it on an emergency basis. Gorsuch, Alito, and Thomas all said they would have blocked the extension. Writing on behalf of the three, Gorsuch said the state board had exceeded its authority. He noted the state legislature has the power to set election rules and had issued a series of changes earlier this year, but left the ballot receipt deadline intact.Justice Amy Coney Barrett, who formally joined the court this week, did not participate in the case because the case needed to be resolved quickly and she did not have time to review the briefings in the case, the supreme court’s public information office said in a statement.Richard Hasen, a law professor at the University of California, Irvine, wrote in a blogpost that he was skeptical that the court would throw out late-arriving ballots after the election given that Pennsylvania voters are being instructed that they do not have to return their ballots by election day in order to have them count.“Without Roberts and Kavanaugh going along, even if Justice Barrett participated in future cases, there would not be five justices to throw out those ballots. It is still a theoretical possibility, however, especially with ballots now being segregated between those arriving by the original statutory deadline and later ballots,” he wrote. “Hopefully the election will not be close enough in either PA or the electoral college and the issue becomes moot in this election.”In the Wisconsin case, Chief Justice John Roberts sided with the court’s conservative justices to reinstate the state’s deadline that all ballots must be received by election day. In a brief explanation Monday, Roberts said the Pennsylvania case was different because it concerned an interpretation of law from a state court, while the Wisconsin case was all in federal court.