Former United States Special Counsel Robert Mueller’s much anticipated testimony before a Congressional Committees will take place on Wednesday where he will be questioned in public for the first time on his probe into Russian interference in the 2016 election and allegations of obstruction of justice by President Donald Trump.

Mueller’s testimony before the House Judiciary and Intelligence Committees comes nearly four months after he completed his investigation and months after the Justice Department released only a redacted version of the report.

Mueller found that Russia interfered in the 2016 campaign to boost Trump’s candidacy, that people in the Trump election campaign had numerous contacts with Russia but concluded that there was insufficient evidence to establish a criminal conspiracy.

And finally Mueller made no determination on whether  Trump committed the crime of obstruction given current Justice Department rules that a sitting President cannot be indicted and as shown in these remarks in May this year.

“If we had had confidence that the President clearly did not commit a crime, we would have said so. We did not, however, make a determination as to whether the President did commit a crime. It explains that under long-standing department policy, a president cannot be charged with a federal crime while he is in office. That is unconstitutional.”

His report also did not exonerate the President despite the Attorney General later controversially stepping in to clear the president of any criminal activity.

Democrats are seeking to illuminate aspects of the report – to bring it to life for the majority of Americans who have not read it and to counter the White House version that the report completely exonerated the President.

“What the Democrats want to get him (Mueller) to do is acknowledge that certain statements are made in the report and that he stands by them. I expect the Republicans on the other hand are not going to address anything in the report. They are going to want to attack Mueller personally,   attack the team that did the investigation and ask him questions about how we ever started on this investigation,” says Constitutional lawyer Stephen Saltzburg.

President Trump has indicated he will not be watching Mueller’s testimony while continuing to raise the matter in public by referring to it as a witch-hunt.

“The Russian witch-hunt okay, first of all its very bad for our country, makes it very hard to deal with Russia and we should be able to – they’re a nuclear power, they have a big country and we should be able to deal with them without having this artificial stuff. They did a report and there was no obstruction, after looking at it, our great attorney general read it, he’s a total professional, he said there’s nothing here, there’s no obstruction, so they referenced no obstruction. So you have no collusion, no obstruction and yet it goes on and they think this is helping them, I personally think it’s hurting them, a lot of people think it’s very bad for them.”

Robert Mueller’s discipline throughout his two-year investigation is likely to be on display in the Congressional chambers on Wednesday, as a former FBI director he is no stranger to the political theatrics of Congress having testified on Capitol Hill more than 60 times.

The Justice Department also sent Mueller a letter earlier this week instructing him to remain within the boundaries of the public version of the report due to issues of Executive privilege.  What remains unclear is the extent to which Mueller’s words will be able to influence parties and their supporters on both sides of the political divide.