Republican leaders have made it clear they oppose a special prosecutor being appointed to take the reins of the FBI’s Trump-Russia probe, even after President Donald Trump abruptly fired FBI chief James B. Comey.

But Deputy Attorney General Rod Rosenstein can bypass Congress and appoint a special prosecutor to take over the ongoing FBI investigation without congressional approval.

Attorney General Jeff Sessions normally would have that power, but he recused himself from the ongoing FBI probe of the Trump campaign’s possible collusion with the Russian government to interfere with the election after it was revealed that Sessions spoke with the Russian ambassador during the campaign.

Democratic Senator Ron Wyden of Oregon suggested to MSNBC host Rachel Maddow on Thursday that Trump could be investigated for not only for election interference, but also for obstructing justice by firing Comey to stop the Trump-Russia probe.

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“From Trump’s own words, it looks like Comey was fired to make the Russia investigation go away,” Wyden tweeted in reference to Trump’s admission to NBC’s Lester Holt that he fired Comey to halt the Trump-Russia investigation by the FBI.

Trump told Holt, “[W]hen I decided to just do it [fire Comey], I said to myself, I said you know, this Russia thing with Trump and Russia is a made up story.”

“Trump (again) shows exactly why we need an independent special counsel and why we need it NOW,” Wyden tweeted in reaction to Trump’s statement to Holt.

https://twitter.com/RonWyden/status/862724441733828612

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Trump also could be investigated for obstruction of justice for reportedly demanding that Comey pledge his loyalty to the president during a private White House dinner on Jan. 27. Comey refused, pledging that he could give a pledge to be “honest.”

Harvard Law School professor Laurence Tribe, a Trump critic, argued that if Trump really did demand a loyalty oath from Comey, it could be an obstruction justice, particularly because Trump later fired Comey.

“The demand for loyalty from the head of the organization investigating those around you, when you have the power to fire that person — if you wrote a novel about obstruction of justice, this would almost be too good to be true,” Tribe told the New York Times.

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Senate Republican Leader Mitch McConnell has expressed his opposition to a special prosecutor, warning that it would “impede the current work being done” by the Senate Intelligence Committee and FBI.

Comey has debunked McConnell’s concerns. During a May 3 hearing by the Senate Judiciary Committee on FBI oversight, Comey testified that if a special prosecutor were appointed, that special prosecutor would simply take over the ongoing Trump-Russia investigation by FBI agents and career prosecutors in the Justice Department.

The then-FBI director testified that a special prosecutor simply would become the lead prosecutor for both “the career level prosecutive team” and FBI agents already working on the Trump-Russia case. For the “prosecutors and the agents, there’s no change except the boss is different,” Comey said.

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Democratic Senator Charles Schumer of New York said he has received assurances from Rosenstein that the deputy attorney general would appoint a special counsel “if one is required.”

The New York Times Editorial Board penned an “Open Letter” to Rosenstein after Trump fired Comey, urging the deputy attorney general to appoint a special prosecutor.

“Dear Deputy Attorney General Rod Rosenstein,” the Editorial Board wrote. “You have one choice: Appoint a special counsel who is independent of both the department and the White House. No one else would have the standing to assure the public it is getting the truth.”

The newspaper noted that only “a handful of Republican senators and representatives expressed concern at Mr. Comey’s firing” and “there is as yet no sign that the congressional investigations into Russian interference will be properly staffed or competently run.”

“And Americans can have little faith that the Justice Department, or an F.B.I. run by Mr. Trump’s handpicked replacement, will get to the bottom of whether and how Russia helped steal the presidency for Mr. Trump,” the Editorial Board said.

FBI agents are worried that without a special prosecutor, the current investigation could be slowed by incremental but harmful tactics, like reassigning FBI agents and slowing the issuance of subpoenas.

A former high-ranking FBI official who worked on aspects of the investigation told the Daily Beast that there’s “no doubt the investigation can be damaged” by interference by Trump loyalists within the FBI and Department of Justice.

“Hard to stop, but definitely subvert,” the former FBI official said.