A growing number of legal experts say President Trump has opened himself up to a charge of obstruction of justice this week when he said "this Russia thing with Trump" was on his mind when he fired FBI Director James B. Comey.
The federal law against obstruction of justice, a felony, is written broadly and applies to pending investigations. It can cover anyone who "corruptly … endeavors to influence, obstruct or impede the due and proper administration of the law under which any pending proceeding is being had before any department or agency of the United States." In another section, the word "corruptly" is defined as "acting with an improper purpose."
Trump's repeated references to the Russia investigation in interviews, tweets and the letter firing Comey could be interpreted as an effort to "obstruct or impede" the investigation, the legal experts said.
The threat is not a completely theoretical one: President Nixon, who was forced to resign under threat of impeachment, and President Clinton, who was impeached, were both accused of obstruction of justice.
Trump, however, would have several defenses. One of the most powerful, although not flattering, lines of defense would be that he did not act "with an improper purpose," but, instead, acted simply because he was impulsively angry.
At first, the president's aides had insisted the FBI chief was dismissed based on the recommendation of top Justice Department officials and because of his botched handling of the 2016 email investigation involving Hillary Clinton.
But Trump in a TV interview on Thursday said he made the decision to fire Comey prior to consulting the Justice Department, because the FBI chief was a "showboat" and was mishandling the department.
He acknowledged that the Russia investigation was one of the things he considered. "In fact, when I decided to just do it, I said to myself, I said, 'You know, this Russia thing with Trump and Russia is a made-up story. It's an excuse by the Democrats for having lost an election that they should have won."
Then on Friday, Trump responded to reports by Comey supporters that during a private dinner months ago, the president demanded Comey pledge his loyalty to him, and Comey refused. The White House denied such a pledge was sought.
In a tweet Friday that many viewed as a veiled threat, Trump wrote, "James Comey better hope that there are no 'tapes' of our conversations before he starts leaking to the press!"
The president has also revealed that he had three conversations with Comey, including one in which he directly asked whether he was under investigation. Trump says Comey three times assured him that he was not.
Comey told a House committee in March that his investigators were looking into possible illegal "coordination" between the Trump campaign and Russians.
Legal experts said the president's statements look to be damaging.
"If one of the reasons the president fired Mr. Comey was to subvert or influence FBI investigations of Trump campaign associates, it is hard to resist the conclusion that this was obstruction of justice," said Ryan Goodman, a New York University law professor and the editor of the Just Security blog.
"No defense lawyer would have wanted their client to utter the incriminating words the president said on NBC to Lester Holt."
Harvard law professor Laurence Tribe agreed. "I think President Trump inadvertently laid a solid basis for an obstruction of justice count in a bill of impeachment with his fateful Lester Holt interview. Trump seems to be his own worst enemy."
Former White House Counsel Bob Bauer, who served under President Obama, said Trump may have "blundered" into legal trouble because he does not understand or accept that the president should not involve himself in a criminal investigation.
Nonetheless, his public comments "may have set into motion legal complications, or worse, for himself and his administration," Bauer wrote on the Lawfare blog.
"It does seem clear that the president has opened himself up to a line of inquiry into whether this call, in conjunction with other actions, represents attempted obstruction of justice.…The president has admitted that he called the director of the FBI to determine whether he was being investigated in what has been officially declared to be an active, ongoing criminal investigation," Bauer wrote. And when the investigation appeared to be expanding, Trump fired Comey, he noted.
But in a criminal case, prosecutors must prove the defendant acted out of a corrupt or improper purpose.
"It's not an easy charge to prove because the key is motivation," said Jennifer Daskal, a law professor at American University.
In part of his NBC interview, Trump said he did not seek to halt the FBI's Russian inquiry, but rather sought to make sure it was done well.
"As far as I'm concerned, I want that thing to be absolutely done properly," the president said. "Maybe I'll expand that, you know, lengthen the time." Regarding the investigation, he added, "I want that to be so strong and so good. And I want it to happen." Those comments give the president and his lawyers evidence to rebut any claim that he sought to obstruct the FBI inquiry.
But Daskal also said Trump's comments could still cause him trouble. "He keeps undercutting his own arguments. And his words and actions increasingly point in the direction that he acted to tamp down the investigation," she said.
In 1974, Nixon faced an impeachment charge of seeking to obstruct the FBI's investigation of the Watergate scandal involving his campaign's effort to "bug" the offices of the Democratic National Committee. And in 1998, Clinton was impeached by the Republican-controlled House for perjury and obstruction of justice for his efforts to conceal his sexual affair with White House intern Monica Lewinsky.
However, unlike Nixon and Clinton, who sought to hide their efforts, Trump has been unusually open and public about his criticisms of the FBI investigation. He tweeted that the "Russian-Trump collusion story is a total hoax, when will this taxpayer funded charade end?"
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