The FBI reportedly rejected a White House request to shoot down stories about alleged communications between Russian operatives and Donald Trump's inner circle.
The formal independence of the Justice Department dates back to Watergate.
After President Richard Nixon resigned because of the scandal, President Jimmy Carter sought to give the Justice Department as much insulation from politics as possible, to keep investigations independent of meddling from the White House or Congress.
Other administrations have since strengthened this distinction, explicitly outlining in Department of Justice memoranda what officials can and cannot do.
But President Donald Trump's administration appears to have flouted this longstanding ethical protocol, experts and former FBI and Justice Department officials say, prompting questions about the impartiality of the FBI's look into Trump and his associates' ties to Russia.
CNN on Thursday reported that the FBI, which is housed within the DOJ, rejected a White House request to publicly shoot down a New York Times story reporting that some members of Trump's presidential campaign had multiple contacts with Russian operatives.
The White House on Friday said it was the FBI's deputy director, Andrew McCabe, who spoke up first, telling Trump's chief of staff, Reince Priebus, in an unprompted fashion that the Times story was "bulls---." He also said Priebus could say publicly that "senior intelligence officials" discredited the story, White House officials have said. The FBI has not commented, citing longstanding protocol during ongoing investigations.
No matter what actually happened between Priebus and McCabe, and who may have initiated the comments about the Times story and the Russia investigation, observers have suggested there seem to have been improper communications about an ongoing investigation.
Timothy Murphy, a former deputy director of the FBI who served under multiple administrations, told Business Insider that he never had any officials try to influence or get information on investigations when he was briefing them at the White House. He said FBI agents are trained not to release any information anyway.
"This White House being new, maybe they think that they can ask the FBI — who knows? You've got a whole new administration — most of them without former government experience — maybe it's something they thought they could ask the FBI to go out and get out front of," he said. "But the FBI did exactly what they were supposed to do, which is say they are not going to comment on active investigations."
That echoed an argument from Gov. Chris Christie, of New Jersey, a political ally of Trump and former US attorney who on Sunday pointed to the fact that "these are all people who have never been in government before."
"I can guarantee this: I don't think the chief of staff will ever have that kind of conversation with the FBI, with an FBI personnel again, nor should he," Christie said on CNN.
The DOJ memo restricting conversations on ongoing investigations says the FBI can inform the White House about investigations if it needs to inform the president about crucial counterintelligence information, which Murphy called a "gray area."
Jane Chong, a national security and law associate at the Hoover Institution, wrote in a post for Lawfare, however, that the national-security exception wouldn't apply in this case.
Murphy added that no one at the White House or the FBI was breaking any US law by discussing investigations.
"You have to be careful about blurring the line between law enforcement and politics," he said. "This isn't something new. Every new administration comes in and they've got to understand where the lines have been drawn, and they rely on memos, they rely on laws, but there is no law about the White House talking to the FBI. There's no law — it's really just been practice and protocol and memos put out by the Department of Justice."
James Wedick, a retired agent who spent 35 years at the FBI, told Business Insider that opening up about ongoing investigations "erodes the public's trust in the bureau."
"The best thing to do if you want to remain independent — and that's what the bureau should be — is to not get yourself involved in the day-to-day operations of the White House," Wedick said. "When bureau executives get themselves into problems of speaking to the White House about investigations, sooner or later you're going to get pulled into the swamp yourself."
Several lawmakers from both sides of the political aisle have criticized Trump for his and his associates' reported ties to Russia. Priebus' conversation with McCabe has only inflamed that criticism.
On Monday, hours after the Republican House Intelligence Committee chair, Devin Nunes, said he had seen "no evidence" of contact between the Trump campaign and Russia, the Democratic ranking member on the committee, Adam Schiff, said a bipartisan commission looking into the matter hadn't started digging yet. He compared the investigation to the commission that investigated the FBI after the September 11, 2001, terrorist attacks and said Congress would need the full cooperation of the FBI to get all the facts.
"I'm concerned that the FBI engaging in conversations with the White House about an ongoing investigation or a potentially ongoing investigation, [and] if the CIA director was brought in to push down news reports," Schiff said. "We have reached no conclusion, nor could we, in terms of issues of collusion, because we haven't called in a single witness or reviewed a single document on that issue as of yet. It's very important that we not prejudge."
Matthew Miller, a former DOJ spokesman under President Barack Obama, has been highly critical of Priebus, and called on Attorney General Jeff Sessions to recuse himself and let a special investigator take over the investigation.
"It is a massive scandal that would lead to the resignation of the chief of staff ... [Priebus] has to go," he said on MSNBC on Thursday night. "Jeff Sessions was also a member of this campaign that is under investigation. He ought to be recused from it — the department's rules are very clear about it. He hasn't recused, and he for all we know is right in the middle of this, too, and he's probably being briefed on the investigation."
Chong, of the Hoover Institution, emphasized in her post on Lawfare the problem with the appearance of someone in Priebus' position trying to influence the FBI.
"The fact that we are left groping in the dark right now, wondering about what happened between the White House and the FBI, means the system ... is under stress," she wrote. "[But] in every version of the story playing out in the press ... the system is at least putting up a strong defense."
If such conversations continue, or the independence of the FBI becomes compromised, Murphy said, it could be a threat to democracy itself.
"Organizations like the FBI are the last line of defense for a democratic society," Murphy said. "They have to be independent. They have to be willing to investigate any party, they have to be willing to investigate any individual, including themselves, and if they're not then we're starting to lose a grip on what the United States stands for."