Senate Majority Leader Mitch McConnell, who last year blocked any attempt to seat Appellate Judge Merrick Garland on the U.S. Supreme Court, thinks the jurist would make the perfect choice to head the FBI in the wake of President Donald Trump’s firing of James Comey, a former adviser said Sunday.

Former CIA Director James Woolsey said, however, the firing is going to make it difficult to find a qualified candidate to lead the agency and Senate Minority Leader Chuck Schumer said Democrats will block any nomination until a special prosecutor is appointed to investigate Russian interference in the 2016 presidential election.

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Trump fired Comey last Tuesday, citing the FBI’s handling of the investigation of Hillary Clinton emails. He then admitted Thursday during an NBC interview he was thinking about the Russia inquiry and questions about whether his campaign colluded with Moscow when he made the decision to oust the FBI director.

Trump also indicated he may have secretly taped his conversations with Comey.

Former McConnell adviser Josh Holmes said on “Fox News Sunday” the Kentucky Republican thinks nominating Garland, former President Barack Obama’s choice to fill the U.S. Supreme Court vacancy created by the death of Justice Antonin Scalia, to head the FBI is “a fantastic idea.”

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“He certainly thinks [Garland] will be qualified. And [McConnell] certainly thinks he would be somebody that he could support.”

McConnell infuriated Democrats when he refused to allow hearings on Garland’s nomination. The high court vacancy was filled last month with the confirmation of Neil Gorsuch.

Garland’s name was floated last week by Sen. Mike Lee, R-Utah, is a bid to head off calls for a special prosecutor.

Woolsey said, however, getting someone qualified to take the job is not going to be easy.

“I think it’s going to be very hard to find a good FBI director who is willing to operate under the circumstances that we’ve seen this week,” Woolsey said on CNN, adding that last week’s turmoil was “very troubling” since the White House couldn’t seem to get its story straight.

Trump and his surrogates initially cited Comey’s handling of the Clinton investigation, with spokesmen saying it was done on the recommendation of Attorney General Jeff Sessions, who had pledged to recuse himself from the Russia investigation, and Deputy Attorney General Rod Rosenstein. Rosenstein then threatened to resign after spokesmen cited a memo he wrote critical of the FBI investigation.

Trump then said he decided to fire Comey on his own and that recommendations by others had nothing to do with it, calling Comey a “showboat.”

Schumer said on CNN’s “State of the Union” Democrats will block any nomination until a special prosecutor that would report to Congress rather than the Justice Department is appointed.

“We will have to discuss it as a caucus, but I would support that move because who the FBI director is, is related to who the special prosecutor is,” he said. “Yes, I think there are a lot of Democrats who feel that way,”

He said the appointment of a special prosecutor would enable people to “breathe a sigh of relief.”