But the significance of Trump’s decision turns on large part on whether Comey’s firing was legal. The optics of ousting the FBI Director amid a probe of Russia’s ties are terrible—as the Wall Street Journal acknowledged in an editorial supporting the decision. But that doesn’t mean Trump didn’t have the authority to do it.

To get a sense of how serious the Comey firing really is, Fortune surveyed the reaction of influential legal scholars who have the expertise to assess Trump’s action. Here’s what they’re saying:

‘A Profoundly Dangerous Thing’

In a widely-circulated blog post titled “The Nightmare Scenario: Trump Fires.. the One Man Who Would Stand Up to Him,” Benjamin Wittes and Susan Hennessey of Lawfare say Trump had the legal authority to fire Comey. But they call the decision “profoundly dangerous” and explain it amounts to an unprecedented disregard for the norms and traditions of the Justice Department and the FBI.

There is no question that the President has the legal authority to remove the FBI director. But there’s also no question that removing the FBI Director in the midst of a high-stakes investigation of Russian influence in the inner circle of the President’s campaign and White House is a horrifying breach of every expectation we have of the relationship between the White House and federal law enforcement.

The post also looks at the memo in which the Justice Department makes the case for dismissing Comey. The scholars agree some of Comey’s actions might merit criticism, including the political nature of his press conferences. But they also say the memo reads like a “bad op-ed” and that “Trump’s clumsy attempt to deny that his own conduct is at issue in the FBI’s inquiry is foolish.”

‘Trump’s Actions Were Entirely Constitutional’

Josh Blackman, a conservative and noted constitutional law professor at the South Texas College of Law, explains on his blog that there is no question Trump had the authority to fire Comey. He notes that, under the Constitution, the President has absolute power to fire “principal officers” like the FBI Director, and notes the firing was accompanied by “fairly elaborate reasons” from the Deputy Attorney General.

Blackman also addresses the issue of whether Trump has plunged the country into a constitutional crisis:

As for whether there is a crisis, we must keep in mind that Comey’s replacement must be approved and confirmed by the Senate. Both Republicans and Democrats will have a say in who heads the agency going forward. At bottom, this is a political question, which ultimately the electorate can decide.

He also suggests the comparisons to Nixon’s “Saturday Night Massacre” are not apt because the circumstances are different and because what Nixon did was obviously illegal.

‘We Need a Special Prosecutor—Badly’

On the popular legal blog called the Volokh Conspiracy, law professor David Post expresses bafflement about the Trump Administration’s reasons for firing Comey at this moment in time. Post notes the abrupt shifts in Trump’s regard for Comey (the President was hailing his performance just weeks ago) and says he would have supported Trump’s decision to fire Comey—if he had made the decision in January. Now, he says, everything looks suspicious:

We need a special prosecutor–badly. Trump and his associates may not be hiding anything about their links to Russian intelligence–but man, they’re sure doing a good impression of people who have a great deal to hide.

Post adds that the Justice Department’s stated reasons for firing Comey sound like a pretext, and that they do not sound the real reasons for why he was fired.

‘Trump Has Crossed the Line’

Harvard law professor Laurence Tribe is an outspoken liberal and critic of Trump, so it’s not surprising he opposes the President’s decision to fire Comey. But Tribe is also a noted constitutional scholar, so his words carry weight.

On Twitter, Tribe argued it’s time for the House of Representatives to commence impeachment proceedings. Here are some of his notable tweets:

Today's monumental question: Will Congress stand by impotently while men too small for the power they wield dismantle our Constitution?

— Laurence Tribe 🇺🇦 ⚖️ (@tribelaw) May 10, 2017

It's now up to Congress to save the Constitution by initiating impeachment proceedings. Trump can't say "You're fired" to the House of Reps.

— Laurence Tribe 🇺🇦 ⚖️ (@tribelaw) May 10, 2017

This fox is emptying the henhouse. Trump has crossed the line. He is covering up high crimes and misdemeanors. https://t.co/zF3EMJDXbE

— Laurence Tribe 🇺🇦 ⚖️ (@tribelaw) May 10, 2017

The Bottom Line

The emerging consensus among legal scholars is that President Trump had the legal authority to fire Comey. But in doing so, he’s set about the biggest political crisis of his young presidency and, for now, it’s too soon to say if this crisis will pass.