Democratic state attorneys general are training their ire over President Trump’s firing of FBI Director James B. Comey on the one man they say can do something about it: Deputy Attorney General Rod J. Rosenstein.

The White House cited a memo Tuesday by Rosenstein as the rationale for Comey’s abrupt dismissal. On Thursday, Trump contradicted that story, saying he had planned to fire Comey anyway, and The Washington Post reported that Rosenstein threatened to resign over the White House’s inaccurate portrayal of his role.

Regardless of his muddled connection to Comey’s firing, 20 Democratic state attorneys general wrote to Rosenstein on Thursday, saying he is the only one who can begin to repair the damage.

Republican leaders in Congress remain opposed to giving up partisan-tainted investigations into Trump aides’ possible collusion with Russia. And Attorney General Jeff Sessions has recused himself from the matter over his own unreported meetings with a Russian official.

That has left Rosenstein, who has long enjoyed bipartisan support as a federal prosecutor in Maryland, as the only one who can appoint an independent special counsel to clear up the extent of “Russian meddling, any collusion by Trump campaign officials, and any coverup,” the Democratic attorneys general wrote.

D.C. Attorney General Karl Racine is a co-chairman of the Democratic Attorneys General Association. (Jabin Botsford/The Washington Post)

“As the chief law enforcement officers of our respective states, we view the President’s firing of FBI Director James Comey in the middle of his investigation of Russian interference in the presidential election as a violation of the public trust,” read the letter sent by Massachusetts Attorney General Maura Healey and signed by 19 others.

“As prosecutors committed to the rule of law, we urge you to consider the damage to our democratic system of any attempts by the administration to derail and delegitimize the investigation.”

For the nation’s Democratic attorneys general, the first four months of Trump’s presidency have amounted to swift role reversal. Where Republican attorneys general for eight years used lawsuits to try to upend President Barack Obama’s Affordable Care Act, it has become Democratic attorneys general fighting Trump’s travel bans and other executive actions.

But in the federal matter of the Trump-Russia investigation, the state attorneys general say there is little they can do but act as a “vertical” check on Rosenstein, pressing him to act in the country’s best interest.

“We are at a crossroads, a real tipping point,” said Pennsylvania Attorney General Josh Shapiro. “Mr. Rosenstein has a chance to stand up and do the right thing, realizing his agency is now compromised. . . . We’re calling this for what it is, an investigation that has run amok.”

D.C. Attorney General Karl A. Racine, who was a former associate White House counsel during the Clinton administration, said Rosenstein can still determine how he will be remembered in this period in American history.

“You make your reputation every day, so whatever Mr. Rosenstein’s reputation was of yesterday, all eyes are on him today and I would urge him to do the most logical, common-sense thing, which is to give the American people what they want: a fair, nonpolitical investigation,” Racine said.

Asked Friday whether Rosenstein had seen the letter, planned to respond or would comment, Justice Department spokeswoman Sara Isgur Flores said she wasn’t sure the letter had been received.

“Since I cant say whether it’s been received, I guess we just have to decline to comment,” she wrote in an email.

Rosenstein has accepted an invitation to brief members of the Senate on Comey’s firing next week.

Republican attorneys general have largely been mum this week amid the furor in Washington over Comey’s firing. A spokesman for the Republican Attorneys General Association said he hadn’t “seen any of our AGs say anything on it.”

In a conference call with The Washington Post, nine Democratic attorneys general, however, said the events since Comey’s firing — including Trump’s assertions that Comey said the president is not under investigation — have only amplified the need for an independent counsel.

“We have not heard from former director Comey what his side of that story is and so I am not going to endorse the president’s version of the truth,” Racine said. “The way the White House has displayed itself, generally, we should be at the least skeptical; they are simply not credible.”

Maryland Attorney General Brian Frosh echoed that sentiment, saying the conversations Trump described Thursday would have been inappropriate for either Trump or Comey.

“The president has the power to hire and fire the director of the FBI, and for him to sit in a room with him and demand to know if he is under investigation is completely inappropriate. If Comey went along with that, he acted inappropriately too, even though I doubt that is what happened.”

The attorneys general also said the assertions made by acting FBI director Andrew McCabe — that the agency has the resources to carry out the Russia investigation — also did not dilute the need for an independent prosecutor.

“It’s not a matter of resources but independence,” said Iowa Attorney General Tom Miller.