President Trump’s decision to fire FBI Director James Comey on Tuesday raises one hugely important question: Did the president dump Comey for mishandling the investigation of Hillary Clinton’s email, as Trump and his team have said? Or was that simply a pretense to fire an independent-minded director who was investigating ties between Trump’s campaign and the Russians?

On the one hand, there’s a strong case that Comey mishandled the Clinton email investigation. In July 2016, Comey publicly scolded the former secretary of state even as he said there were no grounds for criminal charges against her. He sent a letter to Congress on the eve of the presidential election announcing that the investigation had effectively been reopened against the advice of Department of Justice officials, at a time when it may have affected the election results. And then last week, at a congressional hearing, Comey inaccurately described part of that email investigation. Democrats have been attacking Comey for months. Trump now says he disapproves of Comey for the same reasons Clinton has.

But the case for skepticism about the Trump administration’s proffered motives for this move are strong, too. First, Comey’s alleged sins, according to the Trump administration, happened months ago, particularly holding the press conference in which he listed Clinton’s mistakes but did not charge her. If Trump disapproved of them so strongly, he could have dismissed the FBI director much sooner.

Second, Comey and his department have been investigating ties between the Russian government and the Trump camp for months. The investigation seems serious. Trump has now fired a man who was a major potential threat to his presidency.

So the cynical view of Tuesday’s move is that the news of Comey’s latest blunder and Democrats’ constant attacks on the FBI director made it easy for Trump to both fire Comey and potentially blunt criticism of the move as politically motivated. How could Democrats criticize the firing of a man who they have been complaining about for months?

Pretty easily, it turns out. The early reaction from Democrats suggests that whatever concerns they had about Comey are outweighed by worries about Trump. Bob Casey, the Democratic senator from Pennsylvania, called Trump’s move “Nixonian.” Senate Democratic Leader Charles Schumer said, “If we don’t get a special prosecutor, every American will rightfully suspect that the decision to fire #Comey was part of a cover-up,” in a Twitter message.

Even some Republicans expressed wariness about the move. Republican Sen. Richard Burr of North Carolina, who runs the chamber’s Intelligence Committee that is investigating Russian interference in the election, said, “I am troubled by the timing and reasoning of the Director Comey’s termination.” Sen. Bob Corker of Tennessee said the firing “will raise questions.”

Indeed, the firing of an FBI director isn’t quite unprecedented — in 1993, Bill Clinton fired William Sessions, who had been accused of “numerous ethical lapses” — but Comey’s tenure is among the shortest in the bureau’s modern history.

DIRECTOR TERM LENGTH OF TENURE (YEARS) James B. Comey 9/2013 – 5/2017 3.7 – Robert S. Mueller, III 9/2001 – 9/2013 12.0 – Louis J. Freeh 9/1993 – 6/2001 7.8 – William S. Sessions 11/1987 – 7/1993 5.7 – William H. Webster 2/1978 – 5/1987 9.3 – Clarence M. Kelley 5/1973 – 2/1978 4.8 – J. Edgar Hoover 5/1924 – 5/1972 48.0 – William J. Burns 8/1921 – 6/1924 2.8 – William J. Flynn 7/1919 – 8/1921 2.1 – Alexander B. Bielaski 4/1912 – 2/1919 6.8 – Stanley W. Finch 7/1908 – 4/1912 3.8 – Comey’s tenure was shorter than recent FBI directors’ Source: FBI

And as Corker said, this move raises all kinds of questions. Will Trump tap a figure to run the FBI who is committed to the Russia investigation? What will Comey say about his dismissal? Some Democrats, such as Casey, are calling for some kind of special counsel to investigate the controversy, which Trump has so far rejected. But Comey’s firing appears to have increased calls for a more independent investigation. What will be the role of Congress? It has largely been divided along partisan lines on Russia issues, with Democrats pushing for a fulsome investigation and Republicans, who control both chambers, proceeding more cautiously.

Trump, moreover, may not have a ton of credibility with the American people on issues involving Russia. The president has questioned findings about the role of Russian hacking in the election that are agreed upon by everyone else, from virtually all the intelligence agencies to key figures in both parties. Also, Trump has now fired Comey, all of the U.S. attorneys and an acting attorney general who refused to implement his proposed travel ban. A Quinnipiac poll from April found that 55 percent of registered voters disapproved of Trump’s handling of the country’s relationship with Russia. Seventy percent were very or somewhat concerned about Trump’s “relationship with Russia.”

Polls show the public would rather have an independent investigation than leave Congress to handle it. The Quinnipiac survey found 68 percent of respondents supported an independent commission to investigate the Trump camp’s potential ties to the Russian government. And an earlier Quinnipiac poll from mid-March found that only a slim majority, 52 percent, said they would trust the findings of a congressional investigation into Trump’s Russia ties.

After the House passage of the American Health Care Act last week, it seemed like Trump’s second 100 days as president might be more productive than his first 100 days. But Trump has now made a stunning, controversial move that will also force the president to make a number of other complicated decisions. Trump, it seems, wanted Comey out. He will soon learn if it was worth of the cost of actually firing him.