Hundreds of former Justice Department employees are now urging Congress to “swiftly and forcefully respond” should President Trump fire Robert S. Mueller III, the special counsel investigating Russian interference in the 2016 presidential election, or Deputy Attorney General Rod J. Rosenstein, who is overseeing the federal probe.

“It is up to the rest of us, and especially our elected representatives, to come to their defense and oppose any attempt by the President or others to improperly interfere in the Department’s work,” according to a statement signed by former officials who worked under current and previous administrations, some as far back as that of President Richard M. Nixon. The number of signatories has grown to more than 400 as of Sunday afternoon.

The former officials, many of whom said they served with Mueller and Rosenstein at the Justice Department, decried the recent attacks against the agency.

“We served [the Justice Department] out of a commitment to the founding American principles that our democratic republic depends upon the rule of law, that the law must be applied equally, and no one is above the law. … Those of us who served with these men know them to be dedicated public servants committed to these principles,” the statement said.

It further said: “We are therefore deeply disturbed by the attacks that have been levied against the good men and women of the Department. Not only is it an insult to their public service, but any attempt to corrupt or undermine the evenhanded application of the rule of law threatens the foundation of our Republic.”

Trump has launched a protracted attack against the Justice Department, accusing it and the FBI of politicizing the investigative process “in favor of Democrats and against Republicans.” He also mocked the agency in a recent tweet, criticizing it for not cooperating with Congress and calling it an “embarrassment to our country.”

“The President’s unprecedented attack on the Justice Department undermine the rule of law that lies at the heart of our democracy and has enabled our republic to flourish for nearly 250 years,” David Uhlmann, a University of Michigan law professor who worked at the agency for 17 years under three presidents, said in a statement Saturday. “We cannot allow the partisanship that has consumed our politics to erode the principle that no person is above the law.”

President Trump railed against special counsel Robert Mueller’s Russia investigation on March 18, prompting a swift response from lawmakers. (Elyse Samuels/The Washington Post)

Joyce Branda, who served for 37 years under seven presidents, called Trump’s attacks “shameful and baseless.”

“The law is not a weapon in the President’s political arsenal,” Branda, who most recently served under the Trump administration, said in a statement. “A President who fails to understand this and who cannot protect the Department of Justice from political interference is unfit to service.”

The White House did not respond to a request for comment.

Much of Trump’s ire over the past year has been focused on Mueller’s expanding probe, which is also looking into any possible coordination between the Trump campaign and the Russian meddling, along with any other misdeeds discovered, including the possibility of obstruction of justice by the president and the role foreign money may have played to influence the election or the administration’s policy.

Several former advisers and members of the Trump campaign, as well as 13 Russian nationals, have been indicted as part of the probe. But Trump has repeatedly called the investigation a “witch hunt” and slammed Mueller for hiring “13 hardened Democrats” to join his team — even though only nine had made political donations to Democrats and Mueller, himself, is a Republican appointed by Rosenstein, another Republican.

The New York Times reported that Trump had sought to fire Mueller at least twice. The first instance was last June amid media reports that Mueller was looking into possible obstruction of justice, but Trump reportedly backed down after White House counsel Donald McGhan threatened to resign. The president reportedly tried again in early December, when he was angered by reports of subpoenas to obtain information about his business dealings with Deutsche Bank, according to the Times.

At Tuesday’s briefing, White House press secretary Sarah Huckabee Sanders said the president “certainly believes” he has the power to fire Mueller.

The former Justice officials’ statement comes amid reports that Trump allies have been urging the president to fire Rosenstein. The deputy attorney general most recently signed off on an FBI search of the home, office and hotel room of Michael Cohen, Trump’s longtime personal attorney, who is reportedly under investigation for possible bank fraud and campaign finance violations. Cohen had admitted using personal funds to pay an adult-film actress who claims to have had a sexual relationship with Trump in 2006.

The Post’s Robert Costa reported Wednesday that ousted White House chief strategist Stephen K. Bannon is pitching a plan to cripple the investigation into Russian interference in the 2016 presidential election. Part of that plan would be for Trump to fire Rosenstein and for the White House to stop cooperating with Mueller.

Confidants of Rosenstein told NBC News Friday that he seemed to have accepted the possibility of losing his job.

Many of the signatories served under multiple presidents, both Republican and Democrat. Among them is Elizabeth de la Vega, a former federal prosecutor who served under Ronald Reagan, George H.W. Bush, Bill Clinton and George W. Bush.

“I reported directly under Robert Mueller for 4 years,” de la Vega said Friday in a tweet about the former FBI director. “There is no finer public servant anywhere.”

This article, originally published on April 14, has been updated.

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