In an interview Monday morning, Ms. DiFiore, 66, said there was no event that prompted her resignation, but that she was ready to pursue other opportunities after more than six years on the floor. “I did my part,” he said, adding that he had no other work to look forward to but felt it was a good “comfortable time” to move on. He allowed, however, that there would be “another chapter in my professional career.” “What that is, right now, I’m not sure,” she said. The chief justice of the Court of Appeals, which has seven members, is New York’s highest judicial position. Ms. DiFiore will be replaced by an acting chief justice, chosen from among the six other justices on the court, until a successor is named by Governor Kathy Hochul, a Democrat, and confirmed by the state Senate, which is also led by a Democratic supermajority . Ms. DiFiore, the former Westchester County district attorney, was nominated to the court in 2015 by former Gov. Andrew M. Cuomo, who resigned last August. She was the second female chief justice, after Judith S. Kaye, and one of six nominated and confirmed by Mr. Cuomo. Shirley Troutman, the most recent appointee, was nominated last year by Ms. Hochul and confirmed shortly thereafter. The job of chief of the Court of Appeals, to which jurists are appointed to 14-year terms, is heavy, requiring oversight not only of the high court itself but also of the state’s sprawling court system, which has a $3 billion budget and includes 350 courthouses. The pandemic has also severely curtailed the proceedings, with arguments being conducted via video conference rather than in the baroque confines of the Albany courtroom. The New York court could serve as a bulwark against conservative rulings by the U.S. Supreme Court, which recently overturned abortion rights and limited a New York law that regulated the carrying of concealed weapons. But on Monday, Ms. DiFiore dismissed such questions, saying her proudest moments involved her handling of the Covid crisis, the chronically overwhelmed judiciary and maintaining New York’s objective balance. “It’s a brilliant challenge every day,” he said. Judge DiFiore’s legacy may be best defined by a sweeping 32-page opinion issued in April for a divided court that found Democratic leaders had violated the state Constitution when they drew new congressional and state Senate districts. The four-judge majority opinion also said the congressional districts drawn by Democrats violated an express state ban on partisan gerrymandering. The decision angered Democrats, who openly accused the judge of an extrajudicial power grab. Nikolaos Fantos contributed to the report.