The special counsel, Robert S. Mueller III, has approached law enforcement consistently for decades: leading aggressive investigations marked by adherence to precedent and higher office.
WASHINGTON — Long before the convictions last week of two former members of President Trump’s inner circle, the political left’s expectations for the Russia investigation were at a fever pitch.
Democrats predicted that the special counsel, Robert S. Mueller III, would break with a half-century of policy and prosecute a sitting president. One MSNBC panel considered how to arrest him if he refuses to leave the White House. (Answer: “At some point, he is going to have to come out.”)
Mr. Mueller, a lifelong Republican who is an unlikely hero for the anti-Trump resistance, faces a series of crucial decisions in the coming months. Will he subpoena the president? Recommend charges? Will he write a public report? Each could help sway the midterm elections and shape the future of the presidency itself.
For insight on what he will do next, those who have known him for years say, do not look at the mythology that has built up since Mr. Mueller was appointed 15 months ago. Look instead to his four decades of government service.
As he advanced from line prosecutor to top Justice Department official to head of the F.B.I., his time was marked by aggressive prosecutions but also a deference at key moments to precedent, tradition and higher office. “He’s the last guy who’s going to do anything that’s even slightly a departure from the bedrock principles,” said Glenn Kirschner, who worked alongside Mr. Mueller as a homicide prosecutor.
The special counsel investigation has followed a familiar path, colleagues said, largely because Mr. Mueller, a publicity-averse 74-year-old who is as conservative as his go-to outfit (dark suit, white shirt — never blue — and a button-down collar), has stuck to his approach.
“He’s the same guy he’s always been,” said Marilyn Hall Patel, a retired federal judge in San Francisco. “Steady, measured, cautious.”
Assemble a Team
Shortly after taking over as United States attorney in San Francisco in 1998, former colleagues recalled, Mr. Mueller asked all the supervisors in the office to step down. He promptly sent a Justice Department-wide email announcing that “the following positions are now open” — and listing every major prosecution job in Northern California.
Many in the office found it brusque and off-putting. But Mr. Mueller told colleagues that he had learned a management style decades earlier as a Marine platoon commander: You cannot make people do things that they are incapable of doing. So rather than prodding employees, he preferred to move quickly to assemble the best possible team, even if his method was disruptive.
As special counsel, Mr. Mueller has recruited talented prosecutors from across the country, stocking the office both with trusted longtime colleagues and younger prosecutors with sterling résumés. “If you have an opportunity to work with him and learn from him, you do it,” said Melinda Haag, a former United States attorney in Los Angeles who once served as Mr. Mueller’s chief white-collar prosecutor.
Mr. Mueller was not the obvious choice to lead the San Francisco office during the Clinton administration. Those jobs usually go to politically connected lawyers, and Senator Barbara Boxer, Democrat of California, had formed a selection committee to recommend candidates.
Mr. Mueller was tied to the wrong party, having served as a top Justice Department appointee of George Bush. But the San Francisco office was adrift, and career prosecutors at the Justice Department in Washington recommended Mr. Mueller for the job. And though Ms. Boxer had an eye for liberal nominees who diversified the work force, the chairwoman of her committee, Cristina C. Arguedas, had known and respected Mr. Mueller when he was a young prosecutor and she was a public defender.
“It was quite ironic, me going to Barbara Boxer saying, ‘You have to give this plum appointment to this straight white guy who’s also a rock-ribbed Republican,’” Ms. Arguedas recalled.
Judge Patel said she also quietly recommended Mr. Mueller to top Justice Department officials. “I’m a Democrat. He’s a Republican,” Judge Patel said. “But he’s a different kind of Republican, the kind we remember.”
Had Mr. Mueller entertained political ambitions, Republicans could hardly have dreamed up a better pedigree: Robert Swan Mueller III, the son of a DuPont executive and the grandson of a railroad magnate, whose birth was announced in the New York Times society pages. A product of New England prep school and Princeton, he was a lacrosse and hockey star who volunteered for the Marines and earned a Bronze Star and a Purple Heart in Vietnam. He married shortly before enlisting; he and his wife, Ann, a schoolteacher, have two daughters.
But Mr. Mueller never flirted with elected office. After law school at the University of Virginia — one of a few prestigious schools that did not look down on his Vietnam service, he would later say — he began angling for jobs as a prosecutor.
“I wanted to do public service,” he told his law school alumni magazine in a rare interview. “Every day you go to work because you want to; there is always something interesting and exciting. And you do it for somebody else, not just for the salary.”
Move Quickly
As the nation’s top criminal prosecutor during the Bush administration, Mr. Mueller oversaw the high-profile investigations of the Lockerbie bombing, the prosecution of the crime boss John J. Gotti and the sprawling B.C.C.I. financial corruption scandal.
Afterward, he took a sizable step down to return to front-line law enforcement. He became a homicide prosecutor in Washington, a city still reeling from the violence of the crack epidemic of the 1980s and early 1990s.
“I love everything about investigations,” he once said, reflecting on that period. “I love the forensics. I love the fingerprints and the bullet casings and all the rest.”
He demands the same from his subordinates, whom he expects to be steeped in the details. “The thing that would set him off was when someone would come in for a briefing unprepared,” said John S. Pistole, a former deputy F.B.I. director. “Or worse, come in unprepared and act like they were prepared.”
The demand for details is especially grueling because Mr. Mueller is famously impatient. Meetings are not casual affairs with coffee and cross-talk. They follow agendas and then they are over. Mr. Mueller believes in the 15-minute meeting.
Cases, too, are expected to move quickly. Mr. Mueller has little tolerance for meandering prosecutors who lose the plot.
By almost any measure, Mr. Mueller has led the swiftest, most successful independent investigation in modern Washington. In just over a year, he has indicted 25 Russians for trying to influence an American election. He has won a conviction of Mr. Trump’s campaign chairman at trial and secured guilty pleas from two campaign aides and the former national security adviser.
The special counsel prosecutors work late into the night and on weekends, another hallmark of Mr. Mueller’s style. As United States attorney, he walked the halls early in the morning and again in the evening, noting who was punching a clock. For many years as F.B.I. director, he received twice-daily briefings, forcing agents and analysts around the country to work long, odd hours to keep up with his demand for information.
Many agents who worked under him say this personality made him the perfect person to remake the bureau after the Sept. 11 attacks. Others chafed at his unrelenting style. A common criticism is that, after 12 years in office, he had filled the F.B.I.’s senior ranks with two types of people: big personalities whose naturally intense styles matched his, and those who ultimately submitted to his will.
It is not that he was uncaring; colleagues recall his compassion during difficult periods in their lives. Rather, he is focused — at the expense of nearly everything else — on the job.
“He didn’t care about internal politics. He doesn’t care about people’s reactions to things,” Ms. Arguedas said.
She recalled regular meetings with Mr. Mueller in which defense lawyers aired their grievances with his office. He listened intently, she said, and almost always responded, “No.” No soft-pedaling or platitudes. “That’s the way it is.”
“He isn’t trying to be liked,” Ms. Arguedas said. “He doesn’t care about that in the slightest.”
Know Your Role
When Mr. Mueller learned that C.I.A. officers were waterboarding prisoners, locking them in coffins, chaining them to walls and keeping them awake for days, he famously ordered his F.B.I. agents not to participate.
For Democrats and human rights advocates, it was a laudatory but ultimately mealy-mouthed response. The F.B.I., after all, has the authority to investigate torture and prison abuses.
“Why did you not take more substantial steps to stop the interrogation techniques that your own F.B.I. agents were telling you were illegal?” Representative Robert Wexler, Democrat of Florida, asked in 2008.
For Mr. Mueller, the answer was obvious. The Justice Department had declared the C.I.A. tactics legal, and it was not his job to challenge that conclusion.
“There has to be a legal basis for us to investigate,” he told Mr. Wexler. “And generally that legal basis is given to us by the Department of Justice.”
Tough issues or constitutional questions, Mr. Mueller reminded his F.B.I. colleagues, were best left to “Mother Justice.”
“His prosecutor’s background is so deeply ingrained,” said Mr. Pistole, his former deputy. “It was such a key driver for him: What’s the precedent?”
Little precedent exists for the case Mr. Mueller has before him, but 50 years of Justice Department legal policy says that sitting presidents cannot be indicted. Congress, with its impeachment power, may prosecute a president, but the Justice Department may not.
So when Mr. Trump’s lawyer, Rudolph W. Giuliani, announced that he had been assured that Mr. Mueller would abide by that policy, it rang true for those who have known Mr. Mueller for years.
“If the Department of Justice has a legal opinion that says you shouldn’t indict the president, he will feel like he has to follow that,” Ms. Arguedas said. “Because that’s his job. He’s not a guy who’ll say, ‘I don’t care about that legal opinion.’”
Mr. Pistole added: “He’s not looking to push a new legal theory.”
That may be why Mr. Mueller has allowed negotiations to drag on for more than eight months over whether Mr. Trump will sit for an interview. Forcing the issue with a subpoena would test the limits of executive power, and Mr. Mueller does not make such moves lightly.
“Bob is appropriately aggressive, but he’s not going to push things that will bend the law or test procedure in new ways,” said Mr. Kirschner, the former homicide prosecutor. “He wants the public to believe he gave the president every opportunity to have his side heard.”
Judge Patel recalled one dispute with Mr. Mueller during his time in San Francisco. She opposed a Justice Department policy shielding federal prosecutors from oversight by state ethics officials, and she suspected he felt the same way. But he refused to budge, even privately. “It’s an institution,” she said, “and you follow the rules.”
Get Out
Mr. Mueller has granted no interviews or conducted any news conferences during his time as special counsel. Even when his prosecutors revealed in painstaking detail the Russian effort to influence the 2016 presidential election, Mr. Mueller left it to the deputy attorney general, Rod J. Rosenstein, to do the talking.
He is heard from so infrequently that, when Robert De Niro and Kate McKinnon portrayed him on “Saturday Night Live,” neither even tried to mimic his voice. For someone who spent more than a decade in some of Washington’s most important jobs, Mr. Mueller is most often seen in brief archival video clips or old photographs.
Mr. Mueller has many options for ending his investigation, but Mr. Giuliani, the president’s lawyer, has said that Mr. Mueller plans to issue a report on his findings, though the special counsel’s office has never confirmed that path. Any such report — especially a lengthy, damaging one like the report that the independent counsel Ken Starr released about President Bill Clinton — would raise the prospect of a spectacle in Congress.
But the independent counsel law that allowed for such a highly detailed report in the Clinton case expired, and under replacement Justice Department regulations, Mr. Mueller is required only to send a short, confidential summary of his investigation to Mr. Rosenstein.
A less splashy finale suits Mr. Mueller. He likes letting documents do the talking, and as a prosecutor and F.B.I. director, colleagues said, he regularly excised hyperbole or flourish from his prepared public comments.
And history suggests that Mr. Mueller will do all he can to avoid contributing to the political hurricane that will inevitably follow his investigation.
One of the defining moments of his F.B.I. tenure came in 2004, when Mr. Mueller and the deputy attorney general, James B. Comey, raced to the hospital room of the ailing attorney general, John Ashcroft. They were there to intercept officials from the White House, who wanted Mr. Ashcroft to approve a warrantless surveillance program that the Justice Department had said was unconstitutional.
Mr. Mueller and Mr. Comey threatened to quit over the episode, and the White House backed down. That was the end of it as far as Mr. Mueller was concerned, former advisers said. The matter was laid to rest until journalists dug it up years later and Mr. Comey delivered dramatic congressional testimony.
When Mr. Mueller next appeared before Congress, Democrats had to claw to extract even the barest confirmation from Mr. Mueller. “I don’t dispute what Mr. Comey says,” he said bluntly. Mr. Mueller had a powerful political story but went to great lengths to avoid fueling the fight.
“Just tell us the gist of the memorable conversation,” said Representative Steve Cohen, Democrat of Tennessee.
“There was a conversation, yes,” Mr. Mueller responded.
“What was the gist of it, sir?” Mr. Cohen pressed.
“I guess it covered very generally what had happened in the moments before,” Mr. Mueller said, not giving an inch.
“And what had happened in the moments before?”
“Well, again,” Mr. Mueller said, “I resist getting into conversations.”
That moment revealed not only Mr. Mueller’s reluctance to be drawn into a political fight, but also the contrast with Mr. Comey, who would succeed him at the F.B.I. While the two men share mutual respect, friends say the two have never been personally close — despite Mr. Trump’s efforts to paint them as such. Among their biggest differences, Mr. Comey was at ease in the limelight and made contentious decisions in the name of transparency during the investigation of Hillary Clinton.
Mr. Mueller has always preferred to let others do the talking. If, as special counsel, he unearths evidence that Mr. Trump committed a crime, former colleagues say they are certain he will try to hold Mr. Trump accountable. But if the evidence is not clear cut, they say, he will not feel compelled to tell a story just because it involves the president.
“We had cases that were high profile that we declined to prosecute because the evidence didn’t support it,” said Ms. Haag, the former prosecutor, who did not give examples. “There would have been benefits to the office in bringing the case. But he never cared a whit.”
Mr. Pistole and others said they had no doubt that Mr. Mueller was bothered by Mr. Trump’s tweets accusing the F.B.I. and the Justice Department — two agencies he dedicated his life to — of being part of a “deep state” working against his presidency.
As for the president’s remarks about Mr. Mueller and his team personally? “I wouldn’t be surprised if he is somewhat unconscious about all of this,” Ms. Haag said. “I wouldn’t be surprised if it was in one ear and out the other.”
True to form, Mr. Mueller has shown that he is interested in investigating Mr. Trump’s tweets when they might be evidence of a crime. Everything else is just background noise.
“He’s going to find out what there is to find out, and he’s going to say it in the most straightforward, neutral way possible,” Ms. Arguedas said. “And then he’s going to walk away, because his job will be done. He won’t go on any talk shows, and he won’t write a book.”
Sign Up for the Morning Briefing
Get what you need to know to start your day in the United States, Canada and the Americas, delivered to your inbox.
Stay up to date from anywhere. Download the NYT app.