Over nearly two years, special counsel Robert S. Mueller III has operated like a prosecutorial submarine, abruptly surfacing without warning to release indictments or announce guilty pleas and then plunging back down to continue the Russia investigation.

He is ubiquitous and yet invisible — the last known photograph of Mueller was snapped last summer. He has given no interviews, a reticence that has only stoked anticipation for his final report, which appears imminent.

UPDATE: Robert Mueller submits report into whether the 2016 Trump campaign had illegal dealings with Russia »

But Mueller’s unremitting silence and the little-used federal law under which he operates have left deep uncertainty about what lies ahead.


Under regulations written in 1999, the special counsel is required to submit a confidential report to the U.S. attorney general when he completes his probe. Everything else about the process — What will he say? How much will he write? When will it be filed? Will it become public? — is a matter of speculation, leaving official Washington on edge.

“No one really knows or can predict with any uncertainty how this is going to play out,” said Andrew Coan, a University of Arizona law professor who has written a book about presidential investigations. “Not only do we not know what the attorney general is going to do with Robert Mueller’s report, we don’t know what Robert Mueller’s report is going to look like.”

Mueller has given no indication of whether he thinks President Trump obstructed justice, one of the focuses of the probe. Trump almost certainly will not face criminal charges because Justice Department guidelines bar a sitting president from being indicted, however.

TIMELINE: The biggest indictments, guilty pleas and dramas in the Russia investigation »


Still, Mueller’s report could include an incriminating description of Trump’s actions, or even a road map that could be used for impeachment proceedings. Or neither, giving the president the legal and political vindication he has long claimed he is due.

Trump, of course, has already made up his mind about what the Mueller report should say.

“There was no collusion. There was no obstruction. There was no anything,” he told reporters in the Oval Office on Friday. “If it’s an honest report, it will say that. If it’s not an honest report, it won’t.”

Some in Trump’s orbit say his angry tweets about the investigation — he’s condemned it as a hoax or worse hundreds of times — are a signal that he’s bracing for bad news.


“He tends to go back and forth, where one minute he’s upset and tweeting about the ‘witch hunt’ and the next he’s telling you, ‘It’s going to be fine,’ which is basically him telling himself,” said a White House aide, who spoke on condition of anonymity to discuss the president’s mindset.

“The big question is how he responds once it hits,” the aide added. “No one can really plan for that because no one knows what’s coming.”

Trump’s legal team has prepared a rebuttal to Mueller’s report. But they don’t know what they will release because they don’t know what Mueller will say.

One Trump confidant argues that anything less than an overt criminal conspiracy will exculpate Trump in the public eye.


“I think the nation is exhausted of the topic,” said Matt Schlapp, chairman of the American Conservative Union and husband of Mercedes Schlapp, the White House director of strategic communications. “And I think anyone who is a fair-minded voter will look at anything short of Russian collusion as a distraction.”

President Trump listens during a meeting with Chinese Vice Premier Liu He in the Oval Office on Friday. (Alex Wong / Getty Images)

FULL COVERAGE: Robert Mueller finishes his investigation into President Trump’s 2016 campaign »

The special counsel regulations offer little guidance on what to expect. They state that the special counsel “shall provide the attorney general with a confidential report explaining the prosecution or declination decisions,” meaning the decisions not to press charges.


The attorney general is required to notify Congress of any situations in which he overruled the special counsel — for example, if he refused to approve a particular indictment or subpoena. He also can decide that “public release of these reports would be in the public interest.”

That means the key figure in coming weeks may be William Barr, Trump’s new attorney general — not Mueller.

During his Senate confirmation hearing, Barr pledged to “provide as much transparency as [he] can consistent with the law” regarding the Mueller report, but stopped short of promising to release it to the public.

Democrats have demanded the entire report be published. Now that they control the House, they could issue subpoenas to try to pry it out of the Justice Department.


“To maintain that a sitting president cannot be indicted, and then to withhold evidence of wrongdoing from Congress because the President will not be charged, is to convert [Justice] Department policy into the means for a cover-up,” the chairs of six House committees complained in a letter to Barr on Friday. “The President is not above the law.”

David Bossie, a conservative activist who worked on Trump’s 2016 campaign and now serves as an outside advisor to the president, said Democrats may face a backlash if they make too much out of a report that is not damning to the president.

“Because when you overreach, there is inevitably a boomerang,” he said. “You will embolden and empower the president, rather than weakening him.’’

It’s a far different scenario than when the independent counsel wrapped up his investigation into President Clinton in 1998.


Kenneth Starr operated under rules that made him answerable only to a panel of judges, not to the attorney general, and that required him to provide a report to Congress.

He gave them a salacious, detailed account of Clinton’s affair with a White House intern and allegations that he obstructed justice and lied under oath. The report became the basis for Clinton’s impeachment in the House, although he was acquitted in the Senate and served out his term.

Believing Starr had too much leeway, Congress allowed the independent counsel statute to expire and new rules were drawn up — the ones under which Mueller now operates — to provide greater supervision for future investigations.

Mueller already has produced a thick pile of court documents outlining Moscow’s meddling in the 2016 campaign, including the hacking of Democratic Party emails and spreading of misinformation on social media. He has indicted 25 Russians, some of them military intelligence officers, on allegations of violating U.S. law.


He also has exposed a tidal wave of lying by Trump aides, including his former national security advisor, campaign chairman, personal lawyer and others, frequently in connection with their communications with Russian officials or suspected operatives. In all, six former Trump aides or associates have pleaded guilty to various charges.

“It’s a remarkable investigation,” said former acting FBI Director Andrew McCabe, who launched the obstruction investigation aimed at Trump and was later fired. “And it’s one that’s produced tangible, meaningful results. And I think that alone justifies and validates our initial fears, our initial concerns.”

Some questions remain unanswered, most recently involving Roger Stone, a former political advisor to Trump. The indictment said someone directed an unnamed Trump campaign official to reach out to Stone to discuss WikiLeaks’ plans for hacked Democratic Party emails.

“There are some really important parts of the puzzle that Mueller has engaged with but not come to ground with,” said Harry Litman, a University of California law professor and former federal prosecutor.


Mueller appears to have given up efforts to interview Trump, which he had sought for months. In the end, the president answered written questions submitted by Mueller’s team, and only about issues that took place before his inauguration, claiming executive privilege.

There are plenty of signs that Mueller is winding down. Several investigations have been handed off to other offices, and some of his prosecutors have returned to their previous positions at the Justice Department.

Media reports this week variously said Mueller would hand in his report as early as next week or in “the coming days.” Then a Justice Department official told news outlets Friday that nothing would be announced next week.

But the exact timing remains as unclear as ever.


“It had to be before Labor Day. It had to be right after the [midterm] election,” said David Wade, who works for two advocacy groups dedicated to the Russia probe. “The one thing that’s been a constant is there are limits to how much any of us can speculate.”