Special Counsel Robert Mueller has submitted his final report, a still-secret document that closes his 22-month investigation into whether President Donald Trump or those around him conspired in Russia’s interference in the 2016 election.

The Justice Department has notified key lawmakers that Attorney General William Barr has received the report and that he will take some time to review it, according to department spokeswoman Kerri Kupec.

“The next steps are up to Attorney General Barr, and we look forward to the process taking its course. The White House has not received or been briefed on the Special Counsel’s report,” White House spokeswoman Sarah Sanders said.

It’s only the beginning of a struggle between Barr, lawmakers and the White House over how much of Mueller’s findings — and the evidence behind them — will be disclosed to Congress and the public. That fight is likely to escalate from social-media wars between the president and his critics to hearing rooms on Capitol Hill and ultimately to the Supreme Court.

Whatever Mueller found, the completion of his investigation is a turning point for Trump, whose presidency has been dogged by an inquiry he routinely rages against on Twitter as a “witch hunt.”

Before wrapping up his probe, Mueller helped secure guilty pleas from five people involved in Trump’s presidential campaign — including Paul Manafort, who was his campaign chairman, and Michael Flynn, who became his first national security adviser. He’s also indicted more than two dozen Russian hackers and military intelligence officers.

While Mueller never said a word publicly, he and his team of prosecutors used indictments to set out a vivid narrative. It told of hackers tied to Russian intelligence agencies who stole Democratic emails to hurt Trump’s opponent Hillary Clinton and who used social media to help spawn division with false and racially charged messages. It uncovered revealing Russian contacts with Trump’s inner circle, such as a meeting in 2016 where Manafort shared polling data with a fixer tied to Russian intelligence.

But the full extent of what Mueller learned hasn’t been revealed — and may not be if he or Barr decide to withhold details that the special counsel didn’t feel involved crimes he felt he could prosecute.

>> Will the Mueller report be made public? Answers to 6 key questions

Mueller’s decision to issue a final report indicates that he chose not to indict other major figures in his investigation, including members of Trump’s family and the president. However, if he secured any indictments under seal, they could be handed off to other elements of the Justice Department, such as a U.S. attorney’s office.

Mueller’s report could be politically disastrous for Trump if the special counsel says he uncovered evidence that would justify a congressional move to impeach the president — and it’s sure to be claimed as vindication by the president if he doesn’t.

Even so, Trump isn’t necessarily in the clear. He also faces continuing risk from other investigations, with federal prosecutors in New York looking into his company, presidential campaign and inaugural committee. Mueller has been sharing some matters and handing off others to U.S. attorney’s offices in Manhattan; Alexandria, Virginia; and Washington, as well as the Justice Department’s national security division, giving cases that touch on his personal and business affairs a longer lease on life.

Nor is it certain that others close to the president — including Donald Trump Jr., who met with a Russian lawyer after being promised dirt on Clinton — are out of jeopardy. Other prosecutors may well be pursuing investigations related to them.

Barr’s Decision

During Barr’s confirmation hearing in February, he said Mueller’s report would be confidential while “the report that goes public would be a report by the attorney general.” He suggested that he might exclude criticism of Trump as inappropriate for any such public report because Justice Department guidelines argue against indicting a sitting president.

“If you’re not going to indict someone, then you don’t stand up there and unload negative information about the person,” he said.

The Justice Department probably won’t want to release the names of people that Mueller investigated but didn’t charge. Material related to ongoing law enforcement operations, grand jury proceedings or classified intelligence programs is also expected to be withheld from the public.

Ultimately, the Supreme Court may decide the fate of Mueller’s findings. Trump and his lawyers have indicated they want the opportunity to issue a rebuttal on anything damaging to the president and to assert executive privilege over any disclosures of his actions during the presidential transition and the presidency.

But congressional Democrats — who now control the House — say they want broad disclosure of Mueller’s investigative work, citing the earlier success of Republicans in pressuring the Justice Department to release details they said showed anti-Trump bias in the FBI. They have talked of issuing subpoenas to force disclosure and even public testimony by Mueller.

“We’re going to insist on the underlying evidence,” Representative Adam Schiff, the Democratic chairman of the House Intelligence Committee, said in February on ABC’s “This Week.”

“If you take the position that the president cannot be indicted, and the only remedy for improper, illegal or other conduct is impeachment, then you cannot withhold that information from Congress, or essentially the president has immunity,” he said.

Trump told reporters on Wednesday that he, too, wants Mueller’s report made public. “Let it come out,” he said. “Let people see it.”

Collusion, Obstruction

Mueller, a former FBI director, was appointed in May 2017 to conduct one of the most consequential investigations in U.S. history.

Beyond Russia’s election meddling — which U.S. intelligence agencies found was aimed at hurting Clinton and ultimately at helping Trump win — Mueller has been probing possible collusion in the operation and whether Trump sought to obstruct justice.

In particular, Mueller investigated Trump’s efforts to get then-FBI Director James Comey to drop an investigation into his first national security adviser, Michael Flynn. Mueller also investigated whether Trump’s decision to fire Comey in May 2017 constituted obstruction of justice.

Deputy Attorney General Rod Rosenstein appointed Mueller as special counsel days after Comey’s firing.

While Trump has often tweeted that “NO COLLUSION!” with Russia has been found, Mueller’s inquiry has resulted in indictments of figures including the president’s longtime adviser Roger Stone.

Mueller indicted and convicted Manafort, Trump’s former campaign chairman, for a series of financial crimes, and Manafort has been sentenced to 7 1/2 years in prison. He also secured guilty pleas and cooperation agreements from Flynn and Trump’s deputy campaign chairman Richard Gates and he worked with federal prosecutors in New York who secured a deal with former lawyer and fixer Michael Cohen.

Mueller’s investigation cost about $25 million from his appointment in May 2017 through September 2018, according to the latest figures, provided by the Justice Department in December.

It’s been a fast-paced project compared to other major investigations of sitting presidents.

Independent Counsel Kenneth Starr spent four years investigating President Bill Clinton before releasing his 1998 report on the Monica Lewinsky affair, which spun out of a probe into an Arkansas land deal known as Whitewater.

The length and cost of that inquiry — and Starr’s public release of a report with sexually explicit details about Clinton’s relations with Lewinsky, an intern — contributed to Congress letting the law authorizing independent counsels expire. Mueller was named under a less expansive Justice Department regulation providing for special counsels.

It took almost two years for Special Counsel Patrick Fitzgerald to indict Scooter Libby, Vice President Dick Cheney’s chief of staff, for lying to investigators and obstruction of justice in October 2005 in the investigation into the public outing of CIA officer Valerie Plame.

Libby was convicted in 2007 of perjury and obstruction of justice. Trump pardoned Libby last year — and he hasn’t ruled out pardons for some of those facing prison time as a result of Mueller’s work.