Reminder…grounds for appointing special counsel
28 CFR § 600.1 - Grounds for appointing a Special Counsel.
§ 600.1 Grounds for appointing a Special Counsel.
The Attorney General, or in cases in which the Attorney General is recused, the Acting Attorney General, will appoint a Special Counsel when he or she determines that criminal investigation of a person or matter is warranted and -
(a) That investigation or prosecution of that person or matter by a United States Attorney's Office or litigating Division of the Department of Justice would present a conflict of interest for the Department or other extraordinary circumstances; and
(b) That under the circumstances, it would be in the public interest to appoint an outside Special Counsel to assume responsibility for the matter.
https://www.law.cornell.edu/cfr/text/28/600.1