Trump's growing list of high-profile firings

— -- The firing of FBI director James Comey prompted an outcry from both sides of the political aisle last week. But Comey's dismissal wasn't the first time that President Donald Trump revived his old reality show tagline -- "you're fired!" –- in his new role.

There have been a handful of high-profile firings so far during the Trump administration. Three of the four biggest firings have involved people who were reportedly connected to various investigations into Trump, his businesses, or Russian involvement in the U.S. presidential election.

Ahead, a rundown of who Trump has fired and why.

Sally Yates: Jan. 30, 2017

Yates was fired from her post as acting attorney general on Jan. 30 after she instructed the DOJ not to defend Trump’s Jan. 27 executive order barring immigration from seven predominantly Muslim countries. The order was later blocked in court.

The White House said in a statement that Sally Yates "betrayed the Department of Justice by refusing to enforce a legal order designed to protect the citizens of the United States."

"Ms. Yates is an Obama Administration appointee who is weak on borders and very weak on illegal immigration," the statement read.

In a letter to top DOJ lawyers handling the cases related to Trump's executive order on immigration, Yates directed them to hold off on defending it.

"At present, I am not convinced that the defense of the Executive Order is consistent with these responsibilities nor am I convinced that the Executive Order is lawful," Yates wrote.

Yates came back into the spotlight four months later, when she testified in front of the Senate Judiciary Committee in May. She was asked about her repeated warnings to White House Counsel Don McGahn that they were misled by then-National Security Adviser Michael Flynn about the nature of his calls with Russian ambassador Sergey Kislyak before Trump took office.

Michael Flynn: Feb. 13, 2017

Flynn’s transition from longtime campaign surrogate to National Security Adviser was short-lived. Flynn was only in his White House post for 25 days before being asked to resign.

Flynn previously denied that he had spoken with the Russian ambassador to the U.S., Kislyak, in December about sanctions that Obama had imposed on Russia for its suspected interference in the 2016 presidential election. Vice President Mike Pence repeated the denial when asked about the situation in January, but administration officials noted that he was relying on information provided to him by Flynn at the time.

Sources told ABC News that Flynn called Pence three days before his resignation to apologize for misleading him about his conversation with the ambassador.

On March 31, Flynn, via his lawyer, requested immunity as a condition for speaking with members of Congress as part of their investigation into Russian interference in the election. Trump defended his former staffer’s request, tweeting: “Mike Flynn should ask for immunity in that this is a witch hunt (excuse for big election loss), by media & Dems, of historic proportion!”

The immunity request was rebuffed by both the Senate and House Intelligence Committees. Two sources told ABC News that the Senate Intelligence Committee described Flynn’s proposal as a “non-starter.”

Preet Bharara: March 11, 2017

While it is common for some U.S. attorneys to resign from their posts when presidential administrations change, the firing of Preet Bharara, the U.S. Attorney for the Southern District of New York, came as a surprise.

Bharara met with Trump and Attorney General Jeff Sessions in November during the transition and was asked to "stay on." What was apparently not made explicit was whether that request applied to Bharara's full term or just a holdover period. Bharara believed he had been asked to stay on for his full term, a person briefed on the situation told ABC News.

Three months later, on Friday, March 10, the DOJ requested that any remaining "holdover" U.S. attorneys step down. That same day, an official briefed on the situation said that Bharara received a voicemail from one of Trump's assistants, asking him to call back to speak to the president. Bharara didn't know the subject and had no reason to believe he was being fired.

Bharara believed it would be a violation of Department of Justice protocol to have any call with the president. An official briefed on the situation told ABC News that Bharara called Sessions' chief of staff, who agreed with his assessment. Bharara told Sessions' aide that he would be calling Trump's assistant back out of professional respect to say that he could not speak with the president, per DOJ policy, and that is what Bharara did, the official said.

On March 11, Bharara announced –- both via Twitter and a formal statement -- that he had been fired.

Rep. Elijah Cummings, D-Maryland, told ABC News Chief Anchor George Stephanopoulos that Trump's decision to fire Bharara was "curious."

“There's a lot of questions coming up as to whether … President Trump is concerned about the jurisdiction of this U.S. attorney," Cummings said on ABC's "This Week."

Two days before the Justice Department asked the U.S. attorneys to resign, a group of ethics watchdog organizations wrote a letter asking Bharara to investigate whether the Trump family's businesses are receiving financial benefits from foreign governments, thereby violating the emoluments clause in the constitution. The Trump Organization's main offices are in Manhattan, which is located in Bharara's district.

Asked by Stephanopoulos on whether he thinks "there might be a connection" between the letter and Bharara's dismissal, Cummings said: "There very well may -- very well may be."

James Comey: May 9, 2017

According to the White House, Comey lost his job as the director of the FBI because of his handling of the bureau's investigation into Hillary Clinton's emails.

The firing reportedly came days after Comey requested additional money and staffing from the Department of Justice for the ongoing FBI investigation into Russian interference in the presidential election, according to Sen. Richard Durbin, D-Ill., and another U.S. official with knowledge of the situation.

Justice Department spokesperson Sarah Isgur Flores denied that such a request was made, saying the day after Comey’s firing that it was "100 percent false" and "it didn't happen."

Trump initially cited advice "from the attorney general and deputy attorney general of the United States recommending your dismissal as the director of the Federal Bureau of Investigation," in his a letter to Comey.

"I have accepted their recommendation, and you are hereby terminated and removed from office, effective immediately," Trump wrote to Comey.

A source in the Trump administration told ABC News that Deputy Attorney General Rod Rosenstein was so upset that the White House had pinned Comey’s dismissal on him that he had considered resigning.

Trump later said that it was "my decision" to fire Comey and that he "was going to fire [him] regardless of recommendation," however.