Sessions formally notifying Mueller that he does not have authority to act outside of campaign-related cases and cases related to obstruction of Mueller’s investigation would be doing what the Constitution compels: enforcing the Appointments Clause of the Constitution. Additionally, Sessions notifying Mueller that he does not have authority to act outside of campaign-related cases would be exercising Sessions’ court-recognized Constitutional obligation to “direct and supervise litigation” conducted by the Department of Justice. Furthermore, Sessions notifying Mueller that he does not have authority to act outside of campaign-related cases protects against the inappropriate use of the federal grand jury that defendant Manafort now rightly complains about.
Sessions limiting Mueller to the 2016 campaign would also be restoring confidence in democratic institutions, and restore public faith that democratically elected officials.
One thing to remember about Sessions’ recusal: Sessions only recused himself from “any existing or future investigations of any matters related in any way to the campaigns for President of the United States.” This recusal letter limits the scope of Sessions’ recusal to the 2016 campaigns; it does not authorize Sessions’ recusal for anything beyond that.