After shifting the idea to the back burner for a few months, Congress seems ready to move forward on legislation providing more robust protections for special counsel Robert S. Mueller III. With the New York Times reporting on Tuesday that President Trump had pushed to dump Mueller last December — the second time he had actively sought to fire Mueller — it’s apparent that Mueller’s position may be more at risk than members of Trump’s party would like to think.

The proposed legislation, though, appears to leave open significant ways in which Trump could still derail the special counsel’s work — if it were even signed into law.

It’s worth a quick review of the existing boundaries and procedures for the special counsel. Mueller was appointed to his position last May by Deputy Attorney General Rod J. Rosenstein, acting in Attorney General Jeff Sessions’s stead, as Sessions had recused himself from any involvement in investigations into the 2016 campaign.

The statute allowing the appointment of Mueller gives him broad autonomy but includes a key check: The attorney general (or, in this case, the deputy attorney general) can demand that the special counsel explain “any investigative or prosecutorial step” — and can dictate that those steps not be pursued. The special counsel is also bound by the deputy attorney general’s delineation of what he can investigate. And the statute articulates that only Rosenstein (in this case) can fire Mueller and only for an articulated cause. Trump himself has no authority to do so. (There’s a line of argument that postulates Trump could argue that an inability to fire Mueller is an unconstitutional limit on his powers, an argument that would almost certainly end up being evaluated at the Supreme Court.)....
https://www.washingtonpost.com/news/politics/wp/2018/04/11/why-a-proposed-bill-to-protect-mueller-may-not-end-up-protecting-mueller/?utm_term=.9fdc472d3fb4