Factbox: U.S. Justice Department's special counsel probe of Russia

WASHINGTON (Reuters) - U.S. President Donald Trump’s dismissal of FBI Director James Comey has raised questions about the future of the agency’s probe into Russian attempts to sway the 2016 presidential election and possible collusion with Trump’s campaign.

The Justice Department announced on May 17 that Deputy Attorney General Rod Rosenstein had appointed former Federal Bureau of Investigation Director Robert Mueller as a special counsel to lead an independent probe.

Here is what to expect:

* The FBI’s investigation will continue.

Comey’s firing did not end the FBI’s investigation into Moscow’s role in the 2016 election. The career FBI staffers Comey put in charge of the probe will likely continue it, legal experts told Reuters, even as the White House interviews new directors.

* Probes underway in the U.S. Congress will also continue.

Investigations already underway in the Senate Intelligence Committee and House Intelligence Committee and other panels will progress.

Congress could also create a special commission or appoint a special master separate from the committee probes even after Mueller’s appointment, experts said.

Senate Republicans, including some from leadership, previously argued that the appointment of a special counsel could imperil ongoing congressional probes.

Mueller will not have the authority to demand Congress halt a probe. Though criminal probes can at times complicate congressional matters, legal experts said the complications would be indistinguishable from those created by the already ongoing FBI investigation.

* Mueller will steer a parallel probe at the Justice Department.

Mueller will interview relevant witnesses, subpoena documents and, if the evidence merits, work with the FBI to bring criminal charges related to the probe.

*Mueller will operate with a high degree of independence from the Trump administration.

Rosenstein appointed Mueller to head the department’s Russia probe citing department regulations that allow attorney generals to appoint a special counsel from outside the federal government.

The department regulations are “not quite as robust” as a law related to the appointment of a special prosecutor that lapsed in the 1990s, according to Justin Levitt, a professor at Loyola Law School in Los Angeles.

But “the regulations are designed to give the special counsel a great degree of independence - decisions can be overridden but if they are, to make sure that Congress knows about them,” Levitt said.

Rosenstein appointed Mueller because Attorney General Jeff Sessions had to recuse himself from involvement in Russia-related probes because he had not told Congress about his own contacts with Russian officials.

*It would be difficult to fire Mueller from the job.

Only the attorney general - or in this case Rosenstein, as the acting attorney general in matters related to Russia - has the authority to fire a special counsel.

Justice Department regulations state that a special counsel can only be removed “for cause,” such as misconduct, conflict of interest or dereliction of duty, Levitt said.

Though Rosenstein, like Comey, serves at the pleasure of the president and could be removed without cause at any time, Levitt cautioned that doing so in order to jeopardize Mueller’s probe would come at a high political cost. “Each of those actions will come with increasing public and congressional scrutiny,” Levitt said.

Additional reporting by Rick Cowan; Editing by Jeffrey Benkoe and Lisa Shumaker