With FBI director James Comey out, here's what happens next

It's the president's choice. James Comey is out as FBI director, and the future of the bureau's leadership is subject to the whims of Donald Trump.

The U.S. president tweeted Wednesday he would install a new law-enforcement official who "will do a far better job, bringing back the spirit and prestige of the FBI."

Among that new director's tasks will be overseeing the probe into Trump's own campaign's alleged ties with the Russians.

The president had the lawful authority to fire Comey. Now he is able to nominate a successor who could be confirmed over clamorous resistance from Democrats.

Because of a procedural change in the Senate, the next FBI director will only need a simple majority (51 votes) rather than a supermajority (60 votes) to sail through a Senate confirmation. It should be a cakewalk in theory, considering the upper chamber is dominated by 52 Republicans.

"Trump could pick a guy like Chris Christie to take over," constitutional expert and political analyst Paul Lisnek says of the New Jersey governor and Trump loyalist.

"And then the battle would begin, with Democrats saying this is ridiculous, and Republicans saying what a great guy Chris Christie is. But Democrats would have no power. All they can do is scream and yell and say, 'Call your senator.' "

Both Democratic and Republican lawmakers, however, foresee a fraught appointment ahead, with bipartisan calls to at least consider an independent prosecutor to take over the investigation after Comey's departure.

• FBI director draws fire for apparent 'double standard'
• FBI confirms investigation into possible Trump-Russia links

The attorney general's office is interviewing potential interim FBI directors, with the expectation the new chief will be named within days, according to a CNN report citing Justice Department officials. A permanent replacement isn't likely to be confirmed for a while yet under the weight of so much public scrutiny.

For now, Comey's top deputy at the FBI, Andrew McCabe, will step into the role of director.

Senate Democrats will try to use delaying tactics in protest against any nominee that might carry a whiff of being too friendly to Trump. Possible candidates whose names were circulating Wednesday included former New York mayor and Trump loyalist Rudy Giuliani and South Carolina Republican congressman Trey Gowdy.​

"Could this go on for many weeks? Absolutely," Lisnek says.

If Deputy Attorney General Rod Rosenstein heeds the growing chorus of calls to appoint a special prosecutor for the Trump-Russia probe, Lisnek says things may go more smoothly.

Senate Majority Leader Mitch McConnell dismissed that prospect on Wednesday, saying it would be a mistake to halt an investigation already in progress because Comey was fired.

'I've spent the last several hours trying to find an acceptable rationale for the timing of Comey's firing. I just can't do it.'- Republican Senator Jeff Flake

Maybe even more contentious than the stunning personnel change, however, was the administration's reasoning. The official line — that Comey had to go because he publicly criticized former Democratic presidential candidate Hillary Clinton eight months ago for mishandling sensitive State Department emails — isn't holding water on Capitol Hill.

Critics point instead to Comey being ousted just days after testifying as a star witness before a Senate panel about his role in the wide-ranging probe examining potential collusion between Trump's 2016 campaign and the Russians.

"I've spent the last several hours trying to find an acceptable rationale for the timing of Comey's firing," Arizona Republican Senator Jeff Flake tweeted. "I just can't do it."

Megan Brown, a Washington lawyer who formerly worked at the Department of Justice and also with Rosenstein, believes the main challenge will be intense confirmation hearings she expects will take an "extraordinarily political and partisan" tone. 

Although the future of the Trump-Russia probe itself could be thrown into question, Brown is nevertheless confident the Department of Justice will proceed with the investigation "without improper influence or any unnecessary delay" due to a change at the top of the bureau.

At least one former FBI supervisor begged to differ. 

Myron Fuller, a former agent who ran the FBI's Salt Lake City and Honolulu divisions, said the dismissal of a director and installation of a successor more sympathetic to Trump could compromise the ongoing investigation. The case could be dragged out indefinitely, for example.

Deposing a "number one and number two" at an FBI field office could be enough, he said, to "knock over the stool" and effectively kill an investigation.

"People lose interest. People get transferred. People move on to other jobs, and the case gets canned. I've seen that happen. I know it can happen."

'You're kidding!'

Meanwhile, deep misgivings about the rationale for abruptly dismissing Comey were casting a long shadow over Trump's meeting with a Russian envoy.

Russian Foreign Minister Sergey Lavrov feigned ignorance Wednesday when reporters in Washington shouted questions to him about how his meeting with his U.S. counterpart, Rex Tillerson, would be affected by the fallout over Comey's dismissal.

"Was he fired? You're kidding!" Lavrov quipped, turning to the pool of journalists at the White House.

Lawmakers failed to see the humour. 

Despite the official line from the attorney general's office, suspicions are mounting that Comey's ouster was intended to interfere with the Trump-Russia probe. Senate minority leader Chuck Schumer called on all Senate Democrats to convene on the Senate floor on Wednesday morning. 

'Constitutional crisis'

"Were these investigations getting too close to home for the president?" Schumer asked at a press conference.

Senate Democrats Richard Blumenthal and Brian Schatz called the present situation a full-fledged "constitutional crisis."

Republican Senator Richard Burr also raised the alarm, adding that he was "troubled by the timing and reasoning" behind the FBI director's termination. 

But if the purpose of this firing was to derail the counterintelligence probe into the Trump-Russia connections, former U.S. attorney general Alberto Gonzales expects it will only strengthen their resolve to have a thorough investigation.

"It will continue. You've got career individuals at the FBI. You still have an FBI director who will step up and assume that position," Gonzales told CBC News.

"And assuming there's evidence there of wrongdoing, they'll continue that investigation. Nothing should change. Agencies are structured in a way to continue even without the top political appointee. We'll see how it plays out."