Since his appointment 16 months ago as special counsel, Robert S. Mueller III has granted no interviews and held no news conferences. The spokesman for his office is known around Washington as “Mr. No-Comment.” Even public sightings are rare: A photograph of Mr. Mueller at an airport gate, with Donald Trump Jr. in the background, went viral.
Silence as a public relations strategy is risky, especially for someone who is impugned almost daily by Fox News pundits, Trump allies like Rudolph W. Giuliani and tweets from the president himself. Supporters fear that the fusillade is eroding public confidence in the special counsel’s investigation of Russian interference in the 2016 election before Mr. Mueller has a chance to present his findings.
“The risk you always assume is, if your critics and your opponents are the only ones doing the talking, then they get to write the headlines,” said Kevin Madden, a communications strategist who served as a spokesman for the Justice Department under President George W. Bush.
Yet veterans of similar investigations say that keeping quiet may be Mr. Mueller’s only viable option, given the limited set of strategies available for federal prosecutors to communicate with the public. By law, special counsels must follow Justice Department guidelines that restrict them from sharing details about pending investigations, making leaks a potential criminal matter.
Liberals have urged Mr. Mueller to fight back against President Trump’s invective, but predecessors who tried to defend themselves in the press have gotten burned. Kenneth W. Starr, the prosecutor who investigated the Clinton White House, gave impromptu news conferences while taking out the garbage at his Virginia home — and ended up disliked by two-thirds of the public by the time he stepped down.
“It’s hurtful and painful, but a prosecutor’s job is not to necessarily weigh a P.R. battle against political forces that are throwing everything at him,” said Ken Gormley, the author of books about Mr. Starr and Archibald Cox, the special prosecutor who was fired by President Richard M. Nixon during the “Saturday Night Massacre” in 1973.
“Once you’re goaded into becoming a political player,” Mr. Gormley added, “it looks as if you’re just another participant in this mud pit.”
Mr. Mueller, 74, has special reason to be cautious, given a political climate where the subtlest remark can be blown into a scandal. Even if he were to speak publicly, his choice of news outlet and interviewer would most likely be scrutinized for signs of bias.
So Mr. Mueller, a former F.B.I. director and Marine Corps officer known for his self-discipline and meticulousness, has chosen to let his work speak for him. In 16 months, he has produced indictments against three companies and 34 people, including a group of 12 suspected Russian intelligence agents; last month, his work led to a conviction, on eight counts, of President Trump’s former campaign manager, Paul Manafort.
In June, Mr. Mueller’s approval rating hit a low: A Politico poll showed that 36 percent of registered voters viewed him unfavorably, up from 23 percent a year earlier. His reputation has improved since then: A poll released this week by Quinnipiac University found that 55 percent of voters said he was conducting a fair investigation; 32 percent said he was not.
Still, the offensive against the special counsel is unlikely to stop.
In May last year, the day after Mr. Mueller assumed his role, Mr. Trump wrote on Twitter: “This is the single greatest witch hunt of a politician in American history!” The president’s use of “witch hunt” has lately skyrocketed, and he recently exhorted his online followers to “study the late Joseph McCarthy, because we are now in period with Mueller and his gang that make Joseph McCarthy look like a baby!”
Sean Hannity of Fox News made the “Mueller Crime Family” a mantra for his nearly four million nightly viewers, the biggest audience in cable news. The conspiracy theorist Alex Jones of Infowars also joined in, suggesting with no evidence that the special counsel covered up a pedophilia ring and pantomimed shooting Mr. Mueller with a pistol.
Since joining the president’s legal team in April, Mr. Giuliani has been an especially sharp critic, telling Mr. Hannity: “You know how sometimes the cover-up is worse than the crime? In this case, the investigation was much worse than the no-crime.” He has been explicit about the purpose of these attacks: to discredit the investigation in the eyes of the public and make it less likely that Congress will act on its findings.
“What we’re doing here, it’s public opinion,” Mr. Giuliani told CNN in May. “Because eventually the decision here is going to be impeach or not impeach.”
Through it all, Mr. Mueller has held his tongue, save for a single statement on the day he was appointed: “I accept this responsibility and will discharge it to the best of my ability.”
And if the silent strategy is a gamble, he is all in.
Typically in Washington, press aides find ways to guide reporters, even without offering on-the-record quotes. An informal comment like “I won’t wave you off that” can serve as a nod to inquisitive journalists; “I’d steer clear” is a warning that something is off base.
Reporters at several print and television outlets who cover the special counsel said Mr. Mueller’s representatives did not go even that far. Journalists are accustomed to receiving just-the-facts emails from his office, with little more than a link to the latest public legal filing.
Mr. Mueller’s spokesman, Peter Carr, a registered Republican and a former press secretary to Senator Orrin G. Hatch of Utah, works from an undisclosed location and is rarely quoted. (He declined to comment for this article.) On the occasions when Mr. Carr does make a statement, it usually concerns the special counsel’s professionalism, rather than the investigation itself.
After Mr. Mueller was spotted at the airport with Mr. Trump’s son, Mr. Carr issued a careful reply: “If it’s accurate that the other person in the photo was Donald Trump Jr., Mr. Mueller was not aware of him and had no interaction with him.”
What information has emerged about Mr. Mueller’s work, reporters said, often emanates from people outside his team: witnesses or defense lawyers who have had dealings with investigators. Those sources have their own biases, and reporters said the result could be a frustrating lack of clarity on the investigation as a whole.
“He is insulating and protecting himself to the greatest extent possible, which he feels is necessary to protect him and his team from any external attack of being perceived as doing any grandstanding whatsoever,” said Randall Samborn, a former communications director for Patrick J. Fitzgerald, the special counsel whose leak investigation, starting in 2003, led to charges against Vice President Dick Cheney’s chief of staff, I. Lewis Libby Jr.
Mr. Madden, the former Justice Department spokesman, said the opacity was by design. “Mueller has starved the media,” he said, so that reporters will focus on the evidence. “He believes that’s what matters most.”
Partisan warfare over special prosecutors is nothing new. Just as Mr. Trump’s supporters in government and the news media have vilified Mr. Mueller, Bill Clinton’s aides tore into Mr. Starr, labeling him an obsessive zealot.
“As with mosquitoes, horseflies and most bloodsucking parasites, Kenneth Starr was spawned in stagnant water,” wrote James Carville, one of Mr. Clinton’s top strategists, in a 176-page book he published in 1999 that was dedicated to bashing the special counsel. (The title: “… And the Horse He Rode in On: The People v. Kenneth Starr.”)
Unlike the stoic Mr. Mueller, Mr. Starr could not resist returning fire. Papers unsealed last month by the National Archives showed that he authorized one of his lawyers to engage with reporters “to explain a legal position or to rebut allegations that Judge Starr was ‘some sort of right-wing fanatic.’”
Encouraged by allies to defend himself, Mr. Starr hired a professional media wrangler to soften his image and accuse the Clinton White House of spreading misinformation. That did not end well: The Starr spokesman, Charles G. Bakaly III, ended up prosecuted for illegal leaks, though he was ultimately cleared.
Mr. Gormley said that fighting back did not benefit Mr. Starr. “He was perceived by a large segment of the population as someone who was on a witch hunt, out to get the president,” Mr. Gormley said. “In hindsight, he wished he had done a number of things differently.” (Reached for this article, Mr. Starr said he would be open to an interview, but did not respond to subsequent messages.)
Of course, Mr. Starr, like Mr. Cox in the Nixon era, did not have to contend with a social media-savvy president maligning his work hour by hour, or a cable news network whose commentators were overwhelmingly critical of his work. Mr. Mueller, the first special counsel of the Twitter age, is living out a high-stakes case study in prosecutorial public relations.
“The more this investigation moves from the legal arena to the political arena, the riskier it is for Mueller to remain silent,” said Alex Conant, a Republican communications strategist.
And Stu Loeser, a former press secretary to Michael R. Bloomberg and Senator Chuck Schumer, noted that Mr. Mueller was up against a president with an unusual mastery of media.
“The facts alone,” Mr. Loeser said, “may not make the sale for all Americans.”
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