Updated at 10:44 a.m. ET

Special counsel Robert Mueller considered 10 "episodes" involving actions by President Trump that might have constituted obstruction of justice, Attorney General Bill Barr said on Thursday — but the Justice Department concluded they do not amount to a violation of the law.

Barr said he is satisfied Trump had "non-corrupt motives" and that is what prompted him to decide not to prosecute the president for obstruction.

Barr is releasing a copy of Mueller's report later on Thursday morning, but he described how it was drafted — and the information that was removed from it — in a press conference at the Justice Department.

Because investigators did not find a conspiracy between Trump's campaign and the Russian interference in the 2016 presidential election , that suggested Trump wasn't trying to cover anything up, Barr said, about the obstruction aspect of the investigation.

And notwithstanding Trump's frequent public outrage about the matter, the president cooperated with Mueller's inquiry, Barr said.

"There is substantial evidence to show that the president was frustrated and angered by a sincere belief that the investigation was undermining his presidency, propelled by his political opponents and fueled by illegal leaks," Barr said.

Continued Barr: "Nonetheless, the White House fully cooperated with the special counsel's investigation, providing unfettered access to campaign and White House documents, directing senior aides to testify freely and asserting no privilege claims."

The attorney general told reporters he considered it his prerogative to decide what actions to take or not take, what charges to pursue or not pursue, following the completion of the special counsel report.

Mueller did not "indicate" that he considered his mandate to leave decisions about whether to punish the president up to Congress, Barr said.

"We don't convene grand juries and conduct investigations for that purpose," he said.

Mueller's assignment was to file a confidential report to the attorney general, Barr said — not necessarily intended for Congress or the public, Barr added.

That gives him the authority to decide what to do and he is the one who has reached a decision about charges as well as the decision, based on his own discretion, to release it publicly in redacted form, Barr said.

Throughout the press conference Barr struck a familiar refrain from Trump's many tweets and public comments in the past two years, repeating several times that the special counsel found "no collusion" with Russian social media agitation in 2016 or the theft and dumping of emails from political targets in the United States.

Trump welcomed Barr's briefing with a post on Twitter that included an image of himself in a "Game of Thrones" motif with the legend: "Game over."

No invocation of executive privilege

Justice Department officials showed redacted copies of Mueller's report to Trump and White House attorneys before the public release on Thursday, Barr confirmed.

Administration lawyers wanted to review the document to see whether they might want to suppress anything in it under executive privilege — the legal doctrine that permits a president to keep some information within an administration from the public.

"He would have been well within his rights to do so," Barr said of Trump.

Ultimately the White House didn't excise any information, Barr said, and all the redactions in the report were made by the Justice Department.

Democrats angered

Leading Democrats on Capitol Hill complained about Barr's handling of the report. They objected to the early preview for the White House and to a press conference Barr convened before the Mueller report was public.

Rep. Jerry Nadler, D-N.Y., chairman of the House Judiciary Committee, said on Wednesday that Barr "appears to be waging a media campaign on behalf of President Trump, the very subject of the investigation at the heart of the Mueller report."

The chairman later called on Thursday for Mueller to speak for himself about his work, in public, to Congress, in a hearing by May 23.

Congress' two top Democrats agreed.

House Speaker Nancy Pelosi, D-Calif., and Senate Minority Leader Chuck Schumer, D-N.Y., said before the press conference that Barr's "regrettably partisan handling of the Mueller report ... [has] resulted in a crisis of confidence in his independence and impartiality."

Pelosi and Schumer added that "the only way to begin restoring public trust in the handling" of the Mueller investigation is for Mueller himself to testify publicly before the House and Senate "as soon as possible."

The possibility of Mueller testifying before Congress is one that Nadler has raised before. The Judiciary Committee chairman and and Rep. Doug Collins, R-Ga., its ranking member, agree on a desire to have Mueller testify.

Barr said on Thursday that he didn't object, although no hearing is now scheduled. Barr himself is expected to appear before the House and Senate judiciary committees in a few weeks.

Barr briefing follows earlier notice to Congress

The top-line conclusions of Mueller's investigation already were public: Mueller's office did not establish that Donald Trump's 2016 campaign conspired with the Russians who attacked the election , Barr wrote to Congress on March 24.

Nor, wrote Barr, did Mueller's office establish that Trump's actions amounted to the commission of an obstruction of justice offense .

The attorney general told Congress that Mueller's report neither reached a firm conclusion that Trump had broken obstruction law nor did it exonerate him. Accordingly, Barr and Rosenstein concluded that Mueller's findings were insufficient to merit criminal charges for obstruction, Barr wrote.

The attorney general included these conclusions in a four-page letter to Congress about the Mueller report, but the full, nearly 400-page document will not be made public until Thursday.

Barr recently told lawmakers that he would excise sensitive material from it, including grand jury information and foreign intelligence, before providing the full document to Capitol Hill and the public.

Democrats have said that isn't good enough: They want to see everything that Mueller developed, including the underlying information.

Barr has said he is open to negotiations with the leaders of the House and Senate judiciary committees about showing them more from Mueller's work than the public may see.

Nadler argues that lawmakers' access to Mueller's work product does not depend on the discretion of the attorney general and that Congress is entitled to it under law .

Key House committee chairs demanded that work product from Barr in a letter, and the House Judiciary Committee voted on April 3 to authorize the issuance of a subpoena to compel him to provide Mueller's material to Congress.

The redactions

Barr explained to Congress on April 9 why his office was excising material from Mueller's report. He said it would fall into four categories:

— those involving grand jury material, which is kept secret by law;

— those involving foreign intelligence, which is sensitive when it reveals the sources or methods by which it was obtained;

— those that implicate ongoing cases, including the investigations or prosecutions that have spun out of Mueller's investigation;

— and those that would violate the privacy of people whom Barr called peripheral players to the main story.

Barr told lawmakers that the document would include explanations for each area that had been redacted.

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