Moments after being sworn in for his testimony on Capitol Hill Wednesday morning, former special counsel Robert Mueller again doubled down on his commitment not to take his testimony beyond the bounds of his 448-page report.
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"As I said on May 29, the report is my testimony," Mueller told the House Judiciary Committee. "And I will stay within that text."
He stuck largely to that commitment during his more than six hours of questioning before two different House committees. But that didn't make for a shortage of interesting exchanges between lawmakers and the former special counsel, who spent 22-months investigating Russian interference in the 2016 election and examining multiple instances of possible obstruction of justice by the president.
Mueller's testimony brought renewed attention to some key findings of his report and, for the first time since his appointment, showed him pushing back on some allegations made by the president since its release.
Here are five key moments from his testimony:
The Mueller report did not "totally exonerate" the president
Even before Mueller's redacted report was made publicly available in April, President Donald Trump was touting that the investigation’s conclusion had exonerated him.
"It was a complete and total exoneration," Trump said in March, shortly after Attorney General William Barr released a letter which he said summarized Mueller's chief findings.
But Mueller's report, released a month later, challenged Trump's claim. In the report, Mueller wrote that he not find evidence to suggest that members of the Trump campaign or anyone associated with it conspired or coordinated with the Russians, but his team declined to make a traditional prosecutorial decision on obstruction of justice matters.
"While this report does not conclude that the President committed a crime, it also does not exonerate him," Mueller wrote in the report.
During his testimony on Wednesday, Mueller didn't back down from this claim.
"And what about total exoneration? Did you actually totally exonerate the president?" House Judicary Chairman Jerry Nadler asked.
"No," Mueller answered.
The investigation is 'not a witch hunt'
Throughout his nearly two-year investigation, Mueller remained tight-lipped as the president lambasted his investigation. Trump, at various times, has accused the special counsel’s office of harboring political bias against him. The president also took regular swings at Mueller's team, calling the group of prosecutors the "13 Angry Democrats."
But perhaps Trump's most frequently used dismissal of the probe was his accusation that the special counsel's investigation was a 'witch hunt.'
During Mueller's testimony, he -- for the first time since his appointment -- refuted the president's efforts to dismiss his investigation as a witch hunt.
"Your investigation is not a witch hunt, is it?" asked House Intelligence Committee Chairman Adam Schiff.
"It is not a witch hunt," Mueller responded.
Donald Trump Jr.'s interactions with WikiLeaks are 'disturbing' and 'subject to investigation'
Mueller's report focused on members of the Trump campaign's interactions with WikiLeaks, the organization that disseminated stolen Democratic emails during the 2016 election.
His interest in WikiLeaks goes to the heart of the U.S. intelligence community’s conclusion, released in a January 2017 report, that the online organization weaponized and published damaging information provided to it by a hacker from the Russian government on Democratic presidential candidate Hillary Clinton and her campaign.
During the hearing on Wednesday, Rep. Mike Quigley, D-Ill., transcribed and posted on a projector screen praise offered by Trump during the campaign for WikiLeaks. Quigley asked Mueller how he would react to the comments, including Trump referring to WikiLeaks as a "treasure trove" and stating "Boy I love reading those WikiLeaks."
Mueller replied, "Well, ‘it's problematic’ is an understatement in terms of what it displays in terms of giving some hope or some boost to what is and should be illegal activity."
Quigley also asked Mueller about an episode detailed in his report which depicts WikiLeaks corresponding with Donald Trump Jr. and asking for assistance disseminating a link with incriminating information on Clinton.
"This behavior is at the very least disturbing," Quigley said to Mueller.
"Disturbing and also subject to investigation," Mueller said.
Mueller walks back a perceived bombshell
Of particular focus for Democrats on Wednesday was whether the special counsel's decision not to find Trump guilty of obstruction of justice was due to a lack of evidence or simply due to an opinion from the Office of Legal Counsel which states that a sitting president cannot be indicted.
In his report, Mueller demurred on this matter, stating that his report does not exonerate the president but noting that his office did not make a decision on the matter due to the standing Office of Legal Counsel opinion.
Early in his testimony before the first of the two committees on Wednesday, Mueller dropped what appeared to be a bombshell when Rep. Ted Lieu, D-Calif., asked Mueller if the reason he "did not indict Donald Trump is because of the OLC opinion stating that you cannot indict a sitting president."
"That is correct," Mueller responded.
This response got the attention of some who interpreted it to mean that Mueller was suggesting he had sufficient evidence to prosecute the president.
But when Mueller returned for his second round of testimony, he began his opening statements by clarifying his statement.
"I wanted to go back to one thing that was said this morning by Mr. Lieu who said, and I quote, 'you didn't charge the president because of the OLC opinion.' That is not the correct way to say it," Mueller said. "As we say in the report, and as I said at the opening, we did not reach a determination as to whether the president committed a crime."
Mueller sounds the alarm about future election meddling
Several U.S. law enforcement and intelligence entities have warned of efforts by Russia and other foreign adversaries to unduly influence future elections, but hearing Mueller’s foreboding brought new life to the ongoing threat.
"It wasn't a single attempt," Mueller told Rep. Will Hurd, R-Texas, of Russian meddling in the U.S. political process. "They're doing it as we sit here, and they expect to do it during the next campaign."
The Mueller report laid out in painstaking detail Russia’s efforts to sow discord in the American electorate in several ways. Next time, Mueller said on Wednesday, it could be other foreign adversaries, too.
"One of the other areas we have to look at," Mueller said, "many more countries are developing the capability to replicate what the Russians have done."
As foreign adversaries continue to engage in U.S. elections, Mueller expressed concern that campaigns may be more willing to accept help from those state actors.
"I hope it is not the new normal," Mueller said, "but I fear it is."