Acting attorney general Matthew G. Whitaker speaks in New York on Nov. 21. (Peter Foley/EPA-EFE/REX/Shutterstock)

Alberto R. Gonzales served as White House counsel and U.S. attorney general in the George W. Bush administration. He is the dean and Doyle Rogers distinguished professor at Belmont University College of Law in Nashville.

On Nov. 19, three Senate Democrats filed a lawsuit challenging the constitutionality of Matthew G. Whitaker’s appointment as acting attorney general by President Trump. The suit is one of several contesting the appointment. The central question in the senators’ suit is whether an acting attorney general can serve in that position without having been confirmed by the Senate.

The Justice Department’s Office of Legal Counsel, whose opinions are binding on the executive branch, has stated unequivocally that Whitaker’s appointment is constitutional. When I served in the government, I relied on and was guided by the OLC’s opinions, so I accept its judgment that the Whitaker appointment is lawful even though he is not Senate-confirmed. I do so with understanding that OLC opinions are sometimes wrong and overruled by the courts.

Even though Whitaker’s appointment may be lawful, it remains controversial, and he would perform a public service by taking certain steps to make clear that he will carry out his duties in a responsible manner that honors the rule of law.

For almost two years, the Justice Department has been besieged by the president’s constant public criticism of both Attorney General Jeff Sessions, before he was forced to resign on Nov. 7, and special counsel Robert S. Mueller III’s investigation into Russian interference in the 2016 presidential election.

To their credit, Justice Department employees have stayed above the drama and distractions. But one must wonder why the president was willing to stir additional strife by appointing Whitaker when there were Senate-confirmed appointees at the Justice Department qualified to serve as acting attorney general. The interim appointment of Deputy Attorney General Rod J. Rosenstein, who was next in line of succession behind Sessions, certainly would not have generated the type of second-guessing, or litigation, that has met the Whitaker appointment.

Much of the concern about Whitaker is focused on his oversight of the Mueller investigation, which he had openly criticized before his appointment. Those statements call into question his open-mindedness about the investigation and possibly put him in conflict with Justice Department rules governing officials’ recusal that are intended to preserve the integrity of an investigation and to safeguard the department’s reputation from even the appearance of bias or prejudgment. The desire of a prosecutor — even an acting attorney general — to oversee a prosecution must always give way to the department’s needs.

Here are three steps Whitaker could take to alleviate concerns about his impartiality and affirm his commitment to the Justice Department:

First, Whitaker could confirm that he has consulted career ethics professionals in the Justice Department and sought their advice about the possibility that he would need to recuse himself from overseeing the Mueller investigation. He could also reveal their recommendation and explain why he will, or will not, follow it.

Second, if Whitaker does not recuse himself, he could reassure the American people that he will not directly or indirectly stop or interfere with the Mueller investigation in any way that protects or shields the president, his family, close associates or businesses from present or future criminal liability or embarrassment.

Third, Whitaker could confirm that during the Mueller investigation he will not directly or indirectly share any law-enforcement-sensitive information or findings with the White House or outside parties that implicate the president, his family, close associates or businesses. He could also commit to informing Congress immediately if asked by the White House for such information.

Granted, it is not customary for an appointee to a position with prosecutorial discretion, even one serving in an interim capacity, to give such public assurances. But this is not a normal appointment. These public assurances would be unlikely to convince skeptics that the Whitaker appointment is lawful, but they might ease concerns about the president’s motives in choosing Whitaker for this important position at this particular moment.