Anne Joseph O’Connell, a professor at Stanford Law School who studies administrative law, said the ruling could have a broad impact on the administration.

“It opens up a challenge to any acting official serving under Federal Vacancies Reform Act who was named first assistant to Senate-confirmed slot after the last confirmed person departed. “That’s acting US attorneys but it’s not limited to US attorneys,” she said.

“Modern agencies run on delegation in the face of a dysfunctional appointments process,” O’Connell added. “If only the head of the department can do these vacant lower level Senate-confirmed jobs, agencies will grind to a halt.”