Trump, however, has declared that he barely knows Whitaker and has not discussed Special Counsel Robert Mueller’s investigation with him. If so, the White House may have appointed Whitaker in a too-clever-by-half effort to limit the probe led by Mueller. When a senior government official resigns, dies, or cannot do his or her job, the Federal Vacancies Reform Act allows the president to appoint another official of the same federal agency “to perform the functions and duties of the vacant office temporarily in an acting capacity.” Whitaker’s appointment clearly meets the terms of the congressional statute.

Paul Rosenzweig: It wouldn’t be easy for Whitaker to shut down the Trump investigations.

But Whitaker’s appointment must still conform to a higher law: the Constitution. As the Supreme Court observed as recently as this year, Article II provides the exclusive method for the appointment of “Officers of the United States.” The president “shall nominate, and by and with the Advice and Consent of the Senate, shall appoint Ambassadors, other public Ministers and Consuls, Judges of the Supreme Court, and all other Officers of the United States .” The appointments clause further allows that “the Congress may by Law vest the Appointment of such inferior Officers, as they think proper, in the President alone, in the courts of law, or in the heads of departments.”

The Constitution, therefore, recognizes only two types of federal officers. First, there are what the Supreme Court has come to recognize as “principal” officers, who require presidential appointment with Senate advice and consent. Second, there are “inferior” officers, posts for which Congress can choose to allow appointment by the president, courts, or even Cabinet members alone. As the nation’s top lawyer, the attorney general heads one of the four “great” departments of government, along with State, Defense, and Treasury, and the office has existed since the first Washington administration. The attorney general is clearly a principal officer of the government; if he or she is not, it is difficult to imagine what other officer is—the Supreme Court said as much in Morrison v. Olson, the 1988 case upholding the constitutionality of the independent counsel as an inferior officer because she reported to the attorney general as the principal officer.

Whitaker’s appointment violates the appointments clause’s clear text because he serves as attorney general, even if in an acting capacity, but never underwent Senate advice and consent. His defenders might consider the appointments clause to be an antiquated, ceremonial, or obsolete process that could not possibly support the massive number of officials in today’s administrative state. It might need to give way to the practical demands of staffing a modern executive branch with hundreds of thousands of officers and employees, more than a dozen major agencies, and hundreds of commissions, boards, and other odds and ends, with officers who might resign, die, or go AWOL without time to proceed through the 18th century’s idea of a human-resources manual. Defenders might rely on an 1898 Supreme Court decision, United States v. Eaton, which allowed for the temporary appointment of a vice-consul in Thailand “for a limited time, and under special and temporary conditions,” namely, the illness of the consul and the vast distance between the U.S. and Thailand. This is basically the approach of a 2003 Justice Department opinion approving the elevation of an assistant Office of Management and Budget director to acting director, and the likely reasoning of the White House in appointing Whitaker.