If President Donald Trump knew for months that Michael Flynn lied to the FBI, is he guilty of obstructing justice? His lawyer doesn’t think so.

John Dowd reportedly told The Washington Post this weekend that Trump likely knew about Flynn’s erroneous reporting of his conversations with the Russians as early as January, months before he fired then-FBI Director James Comey.

But Dowd has shot down any speculation that his client obstructed justice, saying Trump is president and therefore above the law.

The “President cannot obstruct justice because he is the chief law enforcement officer under [the Constitution’s Article II] and has every right to express his view of any case,” Dowd told Axios in an interview published Monday.

It’s a claim reminiscent of one made in 1977, when former President Richard Nixon said the presidents can essentially behave as they wish.

“Well, when the president does it, that means that it is not illegal,” Nixon said at the time, in a TV interview with David Frost.

Trump raised questions on Saturday about the timeline of his knowledge, tweeting, “I had to fire General Flynn because he lied to the Vice President and the FBI. He has pled guilty to those lies.” Flynn had pleaded guilty to lying to the FBI the day before.

The implication that Trump had known his former national security adviser had lied to the FBI set off alarm bells. The White House had previously said Flynn was fired over false statements he provided to Vice President Mike Pence.

I had to fire General Flynn because he lied to the Vice President and the FBI. He has pled guilty to those lies. It is a shame because his actions during the transition were lawful. There was nothing to hide! — Donald J. Trump (@realDonaldTrump) December 2, 2017

Dowd said he actually drafted the tweet about Flynn being fired, but “did not admit obstruction. That is an ignorant and arrogant assertion.”

“I’m out of the tweeting business,” Dowd told ABC News. “I did not mean to break news.”

Trump and Comey met a few weeks after the president found out about Flynn, according to the Post. It was during that meeting that Comey has said that the president asked him to drop the investigation into Flynn.

That led to speculation that Trump fired Comey to punish him for not giving up on his probe, which may also constitute obstruction of justice.

The president’s control over law enforcement is sometimes regarded as a near-sacred principle in our constitutional system. Daniel Jacob Hemel and Eric Posner, University of Chicago Law School professors

The question over whether a president is constitutionally capable of obstructing justice has no clear answer, according to legal scholars.

“The claim that the president can commit such a crime faces a powerful objection rooted in the Constitution,” two University of Chicago Law School professors, Daniel Jacob Hemel and Eric Posner, explained in a California Law Review article from July.

“Obstruction of justice laws are normally applied to private citizens — people who bribe jurors, hide evidence from the police, or lie to investigators,” they wrote. “The president’s control over law enforcement is sometimes regarded as a near-sacred principle in our constitutional system.”

Yet this conflicts with the constitutional principle that no person can be above the law. That’s why, according to Hemel and Posner, Congress holds the ultimate key to impeachment.

The impeachment charges for both Nixon and former President Bill Clinton involved obstruction of justice. However, Nixon resigned before he could be impeached, and the Senate vote on Clinton’s impeachment resulted in a 50-50 tie. A two-thirds vote from the Senate is needed for a conviction.