investigation has seen numerous departures since its formation last summer.

Mark Corallo

Former Trump legal spokesman Mark Corallo (left) and President Donald Trump's personal attorney Marc Kasowitz arrive to the National Press Club in Washington to read a statement to members of the media, Thursday, June 8, 2017. Pablo Martinez Monsivais | AP

Corallo was an early spokesman for Trump's legal team. He left in July 2017 after just two months in the role, a decision that was influenced at least in part by his frustrations with the conduct in the White House, Politico reported at the time. Multiple outlets have since confirmed that Corallo was interviewed by the special counsel early in 2018.

Marc Kasowitz

Marc Kasowitz Getty Images

Kasowitz, a personal attorney for Trump, was hired in May to lead the president's legal team against the Mueller probe. He left the team in July, although he reportedly maintained contact with Trump after his departure from the team. Kasowitz is currently defending Trump in a defamation lawsuit by a contestant on the president's former television show, "The Apprentice," who says he groped her. Michael J. Bowe, a partner at Kasowitz's law firm, joined Trump's team alongside Kasowitz. It was unclear whether Bowe had resigned or remained on the team. Neither Bowe nor Kasowitz responded to CNBC's requests for clarification.

John Dowd

John Dowd Jin Lee | Bloomberg | Getty Images

Joseph diGenova and Victoria Toensing

Joseph DiGenova NBC

The husband-and-wife legal duo of diGenova and Toensing were tapped in March to join Trump's legal team in the Russia probe. DiGenova, a regular Fox News guest, had spouted conspiracy theories about the Mueller probe's motives against Trump. The White House cited conflicts of interest, however, as the reason the two lawyers could not join the legal team as planned. Toensing represents Corallo, the former legal team spokesman who has been interviewed by the special counsel. "The president is disappointed that conflicts prevent Joe diGenova and Victoria Toensing from joining the president's special counsel legal team," Sekulow said in a statement.

Theodore Olson

Ted Olson, a famed Supreme Court litigator and former Bush solicitor general. Jahi Chikwendiu | The Washington Post | Getty Images

A high-powered lawyer and former solicitor general, Olson was contacted by the White House in March, reportedly about joining the legal team. Like diGenova and Toensing, Olson had conflicts of interest that precluded him from joining. Among those conflicts was the fact that Olson's law firm, Gibson Dunn, represents intelligence-gathering firm Fusion GPS, whose ex-spy authored a dossier alleging salacious connections between Trump and the Kremlin. But in a Monday interview with MSNBC, Olson criticized the conduct in Trump's White House. "This is turmoil, it's chaos, it's confusion and it's not good for anything," Olson said in the interview.

Tom Buchanan and Dan Webb

Dan Webb Getty Images

Trump reached out to Buchanan and Webb in search of legal representation, the white-collar lawyers' firm said in a statement. Both lawyers declined the offer to represent the president "due to business conflicts," according to the firm, Winston & Strawn. "They wish the president the best and believe he has excellent representation in Ty Cobb and Jay Sekulow," the firm said.

Bob Giuffra

Robert Giuffra Getty Images

The Washington Post reported Thursday that Giuffra, a lawyer at Sullivan & Cromwell, had declined to join Trump's legal defense team several weeks earlier. Giuffra was not available for comment.

Robert Bennett

Robert S. Bennett, President Bill Clinton's personal attorney in 1999. William Philpott | AFP | Getty Images

Bennett, who represented President Bill Clinton against an accusation of sexual harassment by Paula Jones, also declined to join the team, according to CNN. Bennett did not immediately respond to CNBC's request for comment.

Emmet Flood

White House Special Counsel Emmet Flood, left, in 2007. Getty Images