The two former FBI chiefs have a unique relationship, stemming in large part from working side by side during a major confrontation with the Bush administration.
By sheer coincidence, this week marked 10 years
since Comey gave his bombshell testimony before the Senate Judiciary Committee about the showdown with President George W. Bush's White House. It began in 2004, when Comey refused to reauthorize an NSA spying program.
Comey was deputy attorney general at the time, and was serving as the acting head of the Justice Department while Attorney General John Ashcroft was in the hospital.
Comey said he had found out that White House chief of staff Andrew Card and White House counsel Alberto Gonzales were headed to Ashcroft's hospital room to get the sick attorney general to OK the program. Comey said he called his chief of staff to get his people to the hospital, and that his second call was to the FBI director.
"I hung up, called Director Mueller, with whom I'd been discussing this particular matter and had been a great help to me over that week -- and told him what was happening," Comey testified in 2007. "He said, 'I'll meet you at the hospital right now.'"
"He's one of the finest people I've ever met," Comey said of Mueller later in the same hearing.
Comey said Mueller had told FBI agents not to let anyone remove Comey from Ashcroft's hospital room "under any circumstances."
Gonzales and Card arrived before Mueller. Comey said they tried to make their case, but Ashcroft refused and deferred to Comey. He said the two left the room, and Mueller arrived shortly after.
In response to a Freedom of Information Act lawsuit from The New York Times
, the government declassified documents revealing Bush made changes to authorize the surveillance program following the hospital incident.
Mueller's notes from the time backed up the account Comey provided to the Senate committee. Comey made his remarks that day to Sen. Chuck Schumer, whose chief counsel was Preet Bharara. Bharara went on become a US attorney, and was fired by Trump.
After news broke of Mueller's appointment, Bharara tweeted: "Reminder: Mueller was FBI Director when he & then-DAG James Comey together intervened at Ashcroft's bedside in 2004 & threatened to resign."