President Trump has named Matthew Whitaker, until recently Chief of Staff to Attorney General Sessions, as acting Attorney General pursuant to the Vacancies Reform Act of 1998. There has been speculation about this unusual move, which seems to be the first time someone has tried to appoint an administrative staffer to a Cabinet position.
Based on my plain text reading of the law (specifically 28 USC 508) it appears that President Trump did not act properly in appointing Mr. Whitaker as acting attorney general.
FYI: 28 USC 508 covers vacancies in the office of attorney general and provides very specific language that suggests Rod Rosenstein should be acting as AG until the Senate confirms a replacement.
The President has argued that he can used the Vacancies Reform Act as an alternative method of filling the vacancy but that does not seem proper to me.
When there is a very specific provision in the law for replacing someone or for a method of succession then I feel that law takes precedence.
In addition, even if we assume the VRA does provide an alternate method (which was the view adopted by a Justice Department Memo in 2007) in this case we also have an Article II issue.
Article II provides that all Cabinet members (principal officers) must be confirmed by the Senate.
In 2007 the memo was issued because President Bush had appointed an assistant AG to act as Attorney General instead of the Solicitor General (which is what Section 508 would provide for)
The key being that the Assistant AG was Senate confirmed while Mr. Whitaker is not. So even if the VRA provides an alternate method, Mr Whitaker is not a qualified choice to serve as AG any more than I would be. There is an 1898 case (United States v. Eaton) which slightly covers this issue and approved of a temporary appointment but that was in relation to an ambassadorial post and involved genuine emergency circumstances (the incumbent counsul was too ill to act, his deputy was not qualified and thus they had no option). That hardly seems to apply here where there are plenty of options from Senate confirmed officials.
Finally we have the conflict of interest in that Mr. Whitaker has publicly (and loudly) opposed the Russia investigation, which would make it difficult for him to oversee it
Admittedly this is more a confirmation issue but that’s why we have the confirmation process.
So in my view, this appointment is invalid for all of the reasons above.