The report also refers to “our investigation” and “our analysis,” reminders that a team of prosecutors, not Mr. Mueller alone, conducted the 22-month inquiry and composed the lengthy document.
Even with the team itself, Mr. Mueller remained somewhat apart. As he set up the special counsel’s office in 2017, he relied on Beth McGarry, a former deputy to Mr. Mueller when he was the United States attorney in San Francisco, to vet candidates, secure funding and find office space, according to a former federal law enforcement official. He had several of his top prosecutors interview top candidates before they met with him.
During the inquiry, his longtime aide Aaron Zebley, a prosecutor on the team, took the lead in dealing with Ed O’Callaghan, a senior Justice Department official helping monitor the investigation, two government officials said. Mr. Mueller often sat in briefly in major interviews or stopped in briefly to thank witnesses for coming in, but rarely asked questions himself. Mr. Mueller never appeared in court during the investigation, and one of his prosecutors, Michael R. Dreeben, issued legal arguments defending the prerogative of the work.
At a sentencing of Paul Manafort, Mr. Trump’s former campaign chairman, nearly every prosecutor and agent who had worked for Mr. Mueller gathered in the courtroom to take in what would be the last major public proceeding of the investigation, including Mr. Zebley and James L. Quarles III, Mr. Mueller’s top two deputies. Mr. Mueller was absent.
To be sure, Mr. Mueller participated directly in the investigation that has come to bear his name. In his news conference, Mr. Barr described a March 5 meeting in which the special counsel repeatedly affirmed he would not make a final call on whether to charge Mr. Trump with obstructing justice.
“He made it clear that he had not made the determination that there was a crime,” Mr. Barr told reporters.
Mr. Mueller might soon talk in public for the first time since his appointment. The House Judiciary and Intelligence Committees have both invited him to testify next month. Judiciary Committee aides were in discussions with the Justice Department about a potential hearing, a spokesman said on Friday.