The investigation into Russian meddling in the 2016 election could be halted or drastically cut back after President Donald Trump replaced Attorney General Jeff Sessions with a vocal critic of Special Counsel Robert Mueller, said two Northeastern law professors.

The first, and most extreme, scenario is that Trump’s newly-selected acting attorney general, Matthew G. Whitaker, fires Mueller. The second scenario is that Whitaker cuts funding for the investigation. The third scenario is that Congress passes veto-proof legislation that would protect Mueller’s investigation until it is completed.

“There are a lot of ways Whitaker might frustrate this investigation,” said Martha Davis, a law professor at Northeastern. “This will be very complicated.”

Davis, and her colleague Dan Urman, who teaches a Northeastern course on the Supreme Court, broke down the three options Thursday.

Scenario one: Whitaker fires Mueller

Whitaker has publicly criticized the scope of Mueller’s investigation into Russian interference in the 2016 election. He’s said he thinks it’s gone too far.

“Whitaker being installed is troubling to those who care about the Mueller probe,” said Urman, who holds joint appointments in the School of Public Policy and Urban Affairs and the School of Law.

One of the ways Whitaker might curtail the investigation is by outright firing the person in charge of leading it: Robert Mueller.

This might prove tricky, though, as Mueller can only be fired for “misconduct, dereliction of duty, incapacity, conflict of interest, or for other good cause,” according to federal regulations.

“’Good cause’ generally means insubordination, fraud—something serious,” Davis said. “There’s no indication so far that Mueller has done anything like that, but ‘good cause’ is subject to interpretation.”

If Whitaker fires Mueller, “we’ll see a showdown that would be resolved by the courts,” Urman said. “Mueller might claim he was fired without legal authority.”

Scenario two: Whitaker cuts Mueller’s budget or limits the scope of his investigation

Because the attorney general controls the special counsel’s budget and establishes his jurisdiction, Whitaker could simply stop funding Mueller’s investigation. This would mean Mueller would have to cut staff and other resources.

He could also severely limit the scope of Mueller’s investigation, something he has already encouraged Rosenstein to do.

“It’s like shutting off the utilities instead of just evicting someone,” said Urman.

Scenario three: Congress passes legislation

Members of Congress have started working on legislation that would protect the special counsel from being fired. In April, the Senate Judiciary Committee approved the Special Counsel Independence and Integrity Act by a 14-7 vote that included approval from both Democrats and Republicans. But the bill still needs full Senate and House approval, as well as sign-off by the president, to become a law.

Activists staged hundreds of protests nationwide on Thursday to demand that neither Trump nor his appointees do anything to obstruct Mueller’s investigation into Russian meddling in the 2016 presidential election. Urman and Davis agreed that the protests could affect how legislators decide to proceed.

“Rule of law and the independence of the Department of Justice are being challenged by the President,” Davis said. “I think protests are appropriate.”

Urman said: “I believe you would see the political system respond if there is near-universal public outrage.”

There is one other consideration: Can Whitaker serve as acting attorney general?

Historically, when a member of the president’s cabinet has been removed from office, the deputy member steps into the role. In this case, it would have meant that Deputy Attorney General Rod Rosenstein would take over as U.S. Attorney General.

This did not happen. Instead, in what Davis described as an “unprecedented” move, Trump announced that Whitaker, who was Sessions’s chief of staff, would stand in as acting attorney general.

Unlike Rosenstein, Whitaker has never been confirmed by the Senate to hold the role. And it’s unclear whether it’s appropriate for Whitaker to serve as attorney general without a Senate confirmation because an unconfirmed person has never been appointed to the role, Davis said.

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