Asha Rangappa in the Washington Post: “If, at the end of his inquiry, Mueller believes that he has gathered enough evidence that would warrant charging Trump with one or more crimes, he can provide that evidence in his final report to the attorney general, along with a recommendation that the president be indicted. The attorney general could approve that recommendation, in which case such an indictment would become public (with its constitutionality litigated in court). But the attorney general could just as legitimately deny the requests based on the internal 1973 policy[.]
“But this action would automatically trigger the reporting requirement to Congress.
“In fact, that might be the only way to guarantee a report goes to Capitol Hill. There is no other requirement for the attorney general to provide Mueller’s final report to Congress — the regulations only require reports on requests that are denied. If Mueller does not recommend indicting the president and the attorney general agrees with that decision, there is no guaranteed mechanism for that information to become public.”
Frankly, I can’t imagine that Mueller’s report could be kept secret for very long. But who knows? This would guarantee that it be made public.