Following Flynn’s resignation, reports said that the FBI was looking into contacts between Russian intelligence and Trump associates during the campaign. There are also lingering questions about whether Flynn acted alone or at the direction of someone in the administration.

Justice Department guidelines state that “no DOJ employee may participate in a criminal investigation or prosecution if he has a personal or political relationship with any person or organization substantially involved in the conduct that is the subject of the investigation or prosecution, or who would be directly affected by the outcome." Several legal experts said that those guidelines and others restricting the conduct of executive branch officials suggested that Sessions should, at the very least, consult ethics officials as to whether recusal is necessary.

“There is a substantial appearance issue,” said John Q. Barrett, who was an associate counsel for the independent counsel looking into the Iran-Contra affair, and is now a professor at St. John’s University School of Law. “I think the wise course would be for the attorney general to step aside from this matter.”

Democrats haven’t said whether they believe an independent counsel is necessary, or whether they would be satisfied with Sessions simply removing himself from decisions involving those inquiries. In 2016, then-Attorney General Loretta Lynch publicly announced that she would accept the recommendations of career attorneys in the Justice Department in the Hillary Clinton email investigation, following a brief meeting with former President Bill Clinton that Republicans said harmed her ability to be impartial.

Sessions, who was sworn in as attorney general less than a week ago, was among the first of Trump’s high-profile endorsers and advised the campaign. White House strategist Steve Bannon told the Washington Post that Sessions was “the clearinghouse for policy and philosophy” in the Trump administration, describing Sessions as “the fiercest, most dedicated, and most loyal promoter in Congress of Trump’s agenda.”

That influence appears to have gone both ways––in 2014, Sessions was a conservative Russia hawk, saying that Russia should be made to “feel pain” for its actions in Ukraine. By August 2016, he was a dove, telling CNN that "this whole problem with Russia is really disastrous for America, for Russia and for the world," and that "Donald Trump is right. We need to figure out a way to end this cycle of hostility that's putting this country at risk, costing us billions of dollars in defense, and creating hostilities.

“I think an argument can be made there is no reason for the U.S. and Russia to be at this loggerheads," Sessions said. "Somehow, someway, we ought to be able to break that logjam."

In October 2016, Sessions told CNN that he wasn’t sure Russia was responsible for the hack and subsequent release of emails belonging to Democratic Party officials. “I haven't had briefings that indicate with any clarity that Russia is doing this,” Sessions said. In his confirmation hearing in January, Sessions told the Senate Judiciary Committee he had “no reason to doubt” the conclusion of the U.S. intelligence agencies that held Russia responsible.