Sanders addressed journalists just one day after President Donald Trump -- citing the recommendation of Deputy Attorney General Rod Rosenstein -- fired Comey, who was overseeing an ongoing FBI investigation into Russia's interference into the 2016 election. Sanders cited Comey's July news conference which he held without notifying his superiors at the Justice Department.
"I think also having a letter like the one that he (Trump) received, and having that conversation (with Rosenstein) that outlines the basic atrocities in circumventing the chain of command in the Department of Justice," Sanders said when asked why Trump's position on Comey changed since the campaign.
"Any person of legal mind and authority knows what a big deal that is, particularly in the Department of Justice; particularly for somebody like the deputy attorney general who has been part of the Justice Department for 30 years and is such a respected person," she added.
During the 2016 campaign, Trump commended Comey for his decision to send a letter to Congress that suggested the FBI was looking into Clinton's email server again. Many Democrats cite Comey's handling of the investigation as a major reason for Clinton's loss.
Still, Sanders said Trump was considering letting Comey go as early as Election Day.
She repeated that the President, as well as Rosenstein and Attorney General Jeff Sessions, had "lost confidence" in Comey.
When asked by CNN's Jeff Zeleny if the president regrets not making the firing decision earlier, Sanders said: "No, I believe the President wanted to give Director Comey a chance."
Sanders said the President made his final decision Tuesday, after talks with Rosenstein and Sessions on Monday and receiving written recommendations from the two on Tuesday.
Many Democrats, though critical of Comey's handling of Clinton's emails, are asking for a special prosecutor to be appointed to lead the investigation in Comey's place. Sessions, they believe, should not be involved, given that he recused himself after it emerged he failed to disclose meetings with a Russian ambassador to Washington.
In an interview with CNN's Wolf Blitzer later Wednesday, Rep. Adam Schiff, D-California, blasted Sanders her word choice.
"For her to say Comey was guilty of some 'atrocity'?" Schiff said. "It's embarrassing."