Updated at 4:35 p.m. ET

Labor Secretary Alex Acosta defended a 2008 plea agreement he oversaw as a U.S. attorney in Florida in which multimillionaire and accused sex trafficker Jeffrey Epstein got a light sentence in exchange for pleading guilty to state charges.

"Facts are important and facts are being overlooked," Acosta told reporters at a news conference Wednesday.

Acosta has come under heavy scrutiny now that federal prosecutors in New York have brought a new case against Epstein, charging him with serious crimes including the sex trafficking of minors. If found guilty, Epstein could face up to 45 years in prison.

Under the 2008 deal, Epstein pleaded guilty to lesser state charges of solicitation of prostitution and was required to register as sex offender. He was given immunity from federal prosecution, served just 13 months in county jail and was allowed to spend his days at his Palm Beach office.

Acosta said Wednesday that his office had handled the case appropriately. He said the Epstein case was complicated by the fact that it had originated with state rather than federal authorities, and that many of the young victims were scared by the prospect of testifying.

Acosta said such a deal might not look very good in retrospect, but that it was the prosecutors' calculation that it was better to secure a guilty plea and register Epstein as a sex offender than risk going to trial and potentially see Epstein go free. "There is a value to a sure guilty plea, because letting him walk, letting what the state attorney was ready to do go forward, would have been absolutely awful," he said.

The labor secretary said his office had been intent on pursuing the case federally but weren't necessarily confident of its outcome. "One of the tough questions in these cases: What is the value of a secured guilty plea with registration, versus rolling the dice? And I know that in 2019 looking back on 2008, things may look different. But this was the judgment of prosecutors with dozens of years of experience," he said.

Democrats including Senate Minority Leader Chuck Schumer and House Speaker Nancy Pelosi have called on Acosta to resign. "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.

On Tuesday, Trump said the plea deal happened many years ago, and that he didn't think Acosta had made the decision alone. "What I do know is that he's been a really, really great secretary of labor. The rest of it, we will have to look at," Trump said.

Trump was quoted in a 2002 New York magazine story as calling Epstein "a terrific guy" and saying that he "likes beautiful women as much as I do, and many of them are on the younger side."

But Trump said Tuesday that he had had a falling out with Epstein and that he didn't think he had spoken to him in 15 years.

House Oversight Chairman Elijah Cummings of Maryland invited Acosta to testify at a July 23 hearing about the deal. Cummings and other House Democrats also sent a letter to the Justice Department's Office of Professional Responsibility in which they said: "There are significant concerns with Secretary Acosta's actions in approving an extremely favorable deal for an alleged sexual predator while concealing the deal from the victims of Mr. Epstein's crimes, which a judge found violated the Crime Victims' Rights Act."

In a letter to Nebraska's Republican Sen. Ben Sasse earlier this year, the Justice Department confirmed its Office of Professional Responsibility is investigating whether lawyers committed misconduct in the handling of the earlier case against Epstein.

A Justice Department spokesman told NPR on Wednesday that the review is "ongoing" with no timetable for its completion. Acosta said at the news conference that he would cooperate with the probe and sit for an interview "even though I don't have to."

The OPR, which conducts internal investigations involving allegations of professional misconduct, has faced criticism in the past over its perceived slow pace and lack of transparency. The Justice Department said the Privacy Act "significantly limits the department from disclosing information concerning individual misconduct allegations."

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