President Donald Trump has for months wanted to remove Jerome Powell as chair of the Federal Reserve. But instead, an investigation by one of his own officials could end up extending Powell’s time at the top of the central bank even after his term formally ends May 15. Trump has nominated former Fed official Kevin Warsh to succeed Powell. Yet Warsh’s confirmation has been delayed by the Justice Department's investigation into brief comments Powell made before the Senate Banking Committee last June about the Fed’s building renovation. On Wednesday, Powell said he would remain as chair of the Fed’s interest rate-setting committee after his term ends if no successor has been confirmed. And he said he could stay even longer if the investigation continues.