I understand the following question is unrelated in every way except it is commentary on legal opinions, but I just didn't want to start another thread.
Recently, Mark Levin has been pushing the opinion of a former college of his when he worked at the Justice Department. Calabresi is now a professor At Pritzker (Northwestern).
http://thehill.com/opinion/white-house/388886-the-mess-rod-rosenstein-madeIn short, because Rosenstein did not lay out potential crime to investigate, the appointment of Mueller was a violation of Trump's civil rights, in that the President alone must nominate all principal officers (basically people that report either directly to the President or have an extreme amount of autonomy), which then must be approved by the Senate.
If Rosenstein had been acting more like Mueller's boss throughout this process, as opposed to just a bystander as he has been, then this would be a moot point, because Mueller would be reporting to someone superior (Rosenstein) and would therefore not be a principal officer.
At least compared to the last time this happened (Starr/Clinton) there does seem to be some differences. I could find articles that indicate Starr was appointed to investigate crimes involving Whitewater land deal. Then later had to get permission to look into the Lewinski affair stuff. Mueller does seem to be doing what he wishes. Manafort in particular is out of left field to most people. He was in charge of the FBI when they first investigated it and for whatever reason charges were never brought. I completely understand why they are now, but I think this just goes to prove the point that Mueller basically has the authority of a principal officer.
Doubt this goes anywhere of course, just curious as to your opinion.
Calabresi expands on his point in this paper
https://papers.ssrn.com/sol3/papers.cfm?abstract_id=3183324