Former Deputy Attorney General James Comey on Tuesday provided dramatic new details of an internal Justice Department rebellion against the White House’s warrantless surveillance program in 2004 and told Congress that the White House had briefly reauthorized the program over the objections of the government’s top legal officials.

In a hearing before the Senate Judiciary Committee, Comey told senators of an extraordinary White House effort to circumvent him in seeking reauthorization for the secret eavesdropping program while Comey was serving as acting attorney general. At that time, in March 2004, then-Attorney General John Ashcroft was in intensive care while being treated for gallstone pancreatitis and had temporarily relinquished his powers to Comey.