“Indefinitely” is how long the Trump administration contends that Deputy Defense Secretary Patrick Shanahan can fill the role of his departed boss, Jim Mattis. President Trump has said he is in “no hurry” to replace Shanahan and his numerous fellow acting cabinet secretaries, telling reporters Sunday that “I sort of like ‘acting'” because “it gives me more flexibility.”
But Shanahan could face legal challenges if he stays in the position too long, some scholars say. The situation is all but unprecedented: There have only been two acting defense secretaries in the 71 years since the role was created. Although there is little debate that the deputy secretary is the most appropriate person to fill in until the Senate can confirm a replacement for Mattis, there is a fierce debate over what time limits — if any — the administration faces to nominate that person.