Robert Mueller has said that the report is his testimony. The following imagines what Republicans might ask or say during Mr. Mueller’s testimony. They probably wont.
Mueller: One, the Special Prosecutor’s team chose not to make a traditional charge/decline-to-charge decision. The DoJ’s Office of Legal Council has ruled that a sitting president cannot be charged and the team accepted the reasoning behind this ruling. (p. 194.)
Republicans: However, you didn’t have to charge President Trump. You could just have found that he did commit obstruction of justice, then leave it to Congress to follow through. Impeachment is a constitutional process. Why didn’t you find this conclusion?
Mueller: Two, the team investigated the facts in order to document occasions where other people had committed obstruction of justice[1] and to document cases where the President may have obstructed justice in order for him to be prosecuted after he leaves office. (pp. 194-195.)
Mueller: Three, the team chose NOT to apply the common legal standard to the evidence that might have led to a decision that the President had committed a crime. (p. 195.)
Republicans:
1) Why not? Such a finding would lead to impeachment by the House. See above.
2.) Or was that because he had not committed a crime?
Mueller: The Federal Government is a sieve, so news of a secret finding would leak. This would cast a shadow over the President’s ability to lead. (p. 195.)
Republicans: So has the Mueller Report cast a shadow over the President’s ability to lead?
Mueller: Four, the team can’t tell if President Trump obstructed justice or did not obstruct justice. (p. 195.)
Republicans (incautiously): Why is that?
Overarching factual issues. (pp. 201-202.)
Mueller: It could not be a typical obstruction case because it concerned the President.
Mueller: First, some of his actions were “facially lawful,” but he also had official powers that could influence other people’s conduct. (p. 201.)
Mueller: Second, obstruction usually is intended to cover-up another crime, but the team did not establish that the President had committed any crime. So the team had consider whether other motives inspired his actions.
Republicans: like punching back against what he believed to be an un-fair investigation?
Mueller: Third, the President often acted in full public view, rather than in secret. Still, this might have been meant to influence witnesses.
[1] Such people can be prosecuted immediately.