U.S. Sen. Susan Collins of Maine on Sunday criticized former FBI Director James Comey for releasing his memoir amid the ongoing Russia investigation, saying it could disrupt the probe.

“That’s what worries me. I cannot see why an FBI director would seek to cash in on a book when the investigation is very much alive,” Collins told NBC’s Chuck Todd on “Meet the Press.” “He should have waited to do his memoir.”

Comey, who as FBI director led the investigation into Russian interference in the 2016 presidential election, last week released his memoir, “A Higher Loyalty: Truth, Lies and Leadership,” which was sharply critical of President Donald Trump. In various television appearances, Comey has suggested it’s possible Russia has leverage over the president and has called Trump “morally unfit” to be president.

His firing last May led to the appointment of Special Counsel Robert Mueller to lead the investigation into Russian interference in the election and possible collusion with the Trump campaign.

[Collins advises Trump against talking about Mueller’s Russia probe]

Collins, a Republican who sits on the Senate Intelligence Committee, which is conducting its own Russia investigation, said that if she were advising future FBI directors, she would tell them two things.

“One, always follow the Department of Justice’s protocols and guidelines, which unfortunately James Comey did not do with the Hillary Clinton investigation and he did not do when he leaked documents that were FBI work documents to a friend of his, knowing that they would go to the press,” she said. “The second would be don’t write a book in the middle of an investigation.”

During her appearance on “Meet the Press,” Collins also waded into a debate over legislation to protect Mueller. Congress needs to have the debate to “send a clear message” to Trump that the legislative branch doesn’t support him taking action against Mueller, she said.

On Thursday, Senate Judiciary Chairman Chuck Grassley, R-Iowa, announced that his committee will vote this week on a bill to protect Mueller over the objections of Senate Majority Leader Mitch McConnell, R-Kentucky, according to USA Today.

[Collins says Trump transition team wrong to reach out to Russia over sanctions]

The bill — sponsored by Republican Sens. Lindsey Graham and Thom Tillis and Democrats Chris Coons and Cory Booker — says that Mueller or any future special counsel can only be fired “for misconduct, dereliction of duty, incapacity, conflict of interest, or other good cause.”

“Where there are issues of national importance, such as the appointment of special counsels and the investigation of a sitting president, Congress must consider its constitutional role and act to make sure that it can avail itself of its traditional checks against the executive branch,” USA Today quoted Grassley as saying.

But McConnell told Fox News on Tuesday that he would not bring the bill to the Senate floor for a vote even if approved by the Judiciary Committee.

Collins said Sunday that McConnell should reconsider his decision, saying “it is important to have a debate on this bill in order to send a clear message to the president that Congress does not support his taking any action with regard to Mr. Mueller’s investigation.”

But it’s also unlikely that Trump would sign the bill into law if passed, Collins added.

[Angus King says it’s ‘premature’ to rule out collusion with Russia]

Congressional Republicans for months have debated whether to pass legislation to protect Mueller. That debate flared up in late January after The New York Times reported that Trump sought in June to fire Mueller weeks after he took over the Russia investigation.

Trump reportedly backed off when White House Counsel Donald McGahn threatened to resign.

So far, Mueller’s investigation has netted more than a dozen indictments, three guilty pleas from former Trump associates, and earlier this month a federal judge handed down the first sentence stemming from the probe, ordering Alex van der Zwaan, 33, a son-in-law of a prominent Russia-based banker, to serve 30 days in prison.

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