WASHINGTON – The top Democrats in Congress have called on Labor Secretary Alexander Acosta to resign over a past plea deal he cut as a U.S. attorney that gave a light sentence to multimillionaire Jeffrey Epstein, who had allegedly engaged in sex acts with dozens of minors.

In an 11 p.m. tweet Monday, Pelosi said Acosta "must step down" because "he engaged in an unconscionable agreement" with Epstein, which was "kept secret from courageous, young victims preventing them from seeking justice. This was known by @POTUS when he appointed him to the cabinet. #AcostaResign."

On Tuesday, Senate Minority Leader Charles Schumer, D-N.Y., said he was "calling on Secretary Acosta to resign" in a speech from Senate floor.

"It is now impossible for anyone to have confidence in Secretary Acosta's ability to lead the Department of Labor. If he refuses to resign President Trump should fire him," Schumer said. "Instead of prosecuting a predatory and serial sex trafficker of children, Acosta chose to let him off easy."

Epstein, 66, who is known for his ties to powerful figures including Trump and former President Bill Clinton, was arrested Saturday on charges of sex-trafficking girls as young as 14. He pleaded not guilty in a Manhattan federal court on Monday. The indictment against him says he "sexually exploited and abused dozens of minor girls at his homes" in New York City and Palm Beach, Florida.

Acosta has stood by his decision to offer Epstein a deal, and on Tuesday he tweeted that he was "pleased" that prosecutors in New York are "moving forward with a case based on new evidence."

Trump told reporters that he thought Acosta has been "an excellent secretary of labor" and that he "feels badly" about the criticism he is facing. He also said he'll look "very carefully" at the plea deal, which he said was "a long time ago" and was a decision made "by a lot of people" in addition to Acosta.

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In November, the Miami Herald published an in-depth look at the 2007 deal that showed that Acosta – then the top federal prosecutor in Miami – was directly involved in negotiating a deal with Epstein's lawyers in which the wealthy and influential hedge fund manager agreed to plead guilty to two state felony prostitution charges, pay restitution to his victims, register as a sex offender and serve 13 months in county jail.

But Epstein, who had faced a possible life sentence if convicted on the federal charges, was able to serve much of that sentence from his Palm Beach office as part of a work-release program.

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Epstein's alleged co-conspirators were granted immunity and the federal non-prosecution agreement was sealed, which meant it was hidden even from the girls Epstein was accused of abusing when they were teenagers, the Herald revealed.

Federal prosecutors identified three dozen accusers, according to the Herald, but the newspaper said it found 80 girls who were abused between the ages of 13 and 16.

In response to those reports, Democratic lawmakers last year called for a Justice Department investigation into Acosta's role in Epstein's plea agreement. Sen. Ben Sasse, R-Neb., who called Epstein a "monster," joined that call, and in February the Justice Department launched an investigation into potential "professional misconduct" in Epstein's plea deal. That same month U.S. District Court Judge Kenneth Marra ruled that Acosta and his team had violated the Crime Victims Rights Act by concealing the plea agreement from Epstein's victims.

On Tuesday, Schumer called for the results of the Justice Department's investigation into the deal to be made public and for Senate hearings into the matter. Sen. Lindsey Graham, R-S.C., who heads the Senate Judiciary Committee, told reporters he was open to such hearings.

"If this plea deal doesn’t withstand scrutiny, then it would be the job of the Judiciary Committee to find out how it got off the rails," he said, according to The Hill.

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"My understanding is that’s a very complicated case," then-White House Press Secretary Sarah Sanders said in response to the ruling. "But that they made the best possible decision and deal they could have gotten at that time."

Sen. Tim Kaine, D-Va., asked Acosta about The Washington Post's report at his confirmation hearing in 2017 and why Epstein was never indicted on federal charges despite an 82-page memo detailing federal prosecutors' findings and a 53-page indictment they compiled.

Acosta defended the deal he cut with Epstein's lawyers, saying that there was a "broadly held" view among the prosecutors in his office that "based on the evidence," a "plea that guarantees someone goes to jail" is "a good thing,’’

Acosta went on to be confirmed by a vote of 60-38.

When confronted again about the plea deal during a House Appropriations subcommittee hearing in April, Acosta said he understood the "frustration" around the agreement but argued that if he had not struck the deal, Epstein "was going to get off" with no jail time.

"It was the work of our office that resulted in him going to jail. It was the work of our office that resulted in his register and put the world on notice that he's a sex offender," he said.

Presidential candidate Sen. Amy Klobuchar, D-Minn., joined in the call for Acosta's resignation on Tuesday.

"Since when do underage girl sex ring traffickers get to go to their office every day while they serve their time?" Klobuchar, a former prosecutor, said in a tweet criticizing the 2007 plea deal. "The victims should have had a say. That’s what the law says.

"I didn’t vote for former Florida U.S. Attorney Acosta to begin with, and he should step down," she said.

Other 2020 Democratic candidates quickly followed suit.

"Alex Acosta should resign as Labor Secretary. We need leaders committed to fighting for justice for survivors of abuse, not protecting predators," tweeted California Sen. Kamala Harris, who is also a former prosecutor.

"I opposed Secretary Acosta's nomination, and voted against his confirmation. The last few days have only highlighted how ethically compromised and unfit to serve he is. Acosta must resign – now," tweeted Massachusetts Sen. Elizabeth Warren.

"Acosta should step down," said New Jersey Sen. Cory Booker.

"Acosta must resign," tweeted former Texas Rep. Beto O'Rourke.

"I think he should be asked to resign because of his role in the process with Epstein," said Sen. Bernie Sanders, I-Vt., in an interview with MSNBC's Andrea Mitchell.

Montana Gov. Steve Bullock said Acosta had "broken the public trust" and needed to resign.

Former Vice President Joe Biden also called on Acosta to resign, writing on Twitter that "The abuse of a child is one of the most heinous, despicable abuses of power imaginable."