Let's say (hypothetically) that Mueller uncovers irrefutable evidence of Trump doing something highly illegal- such as conspiring with Vladimir Putin to win the election. Ignore for now whether it may or may not have happened.
Mueller discusses this with William Barr and is told that under no circumstances can you indict a sitting president. Because that's the DoJ policy right? Even if the President has been shown to be irrefutably involved in criminal activities, he can't be criminally liable for it.
So Mueller- being the detailed prosecutor that he is, puts all those facts into the report. Facts that would absolutely guarantee the impeachment of Donald Trump. And then those facts reach the desk of William Barr- the guy that was literally picked by the very guy who has been fingered in a criminal prosecution.
This is what I mean by above the law. It is entirely possible that Donald Trump has committed criminal actions- and yet cannot be indicted by the Special Counsel- because of the policy of the DoJ- and yet cannot be impeached for those very same crimes because a guy that was hand-picked by the criminal himself decides to shield him from any and all accountability.
This is why I think that the House can and must do everything they can to secure the full, unaudited report from Mueller; and if not, subpoena him to appear before the House. This is not a trivial matter. This is something that goes to the very heart of the American democratic system and as such, should be given comparable attention.
