Labor Secretary Alexander Acosta is facing calls from many top lawmakers, including House Speaker Nancy Pelosi (D-California), to step down after it was revealed he negotiated a plea agreement with Jeffrey Epstein that allowed the billionaire to serve an extremely short sentence for a long list of sex crimes.

“As US Attorney, he engaged in an unconscionable agreement w/ Jeffrey Epstein kept secret from courageous, young victims preventing them from seeking justice,” Pelosi wrote about Acosta on Twitter.

Acosta, 50, reportedly said the plea deal, which saw the now 66-year-old New York financier serve just 13 months behind bars for sex trafficking and conspiracy charges, represented the “toughest deal” available in this case. The United States Labor Secretary previously worked as a federal prosecutor in Epstein’s case in Miami more than ten years ago and the agreement was reportedly reached in 2008.

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Epstein, whom President Donald Trump praised as a “terrific guy” years ago, was arrested in New Jersey over the weekend. New York officials found a trove of nude and other lewd photos of dozens of underage girls as young as 14 at the billionaire’s mansion in Manhattan. Epstein,who is now a registered sex offender, was charged and indicted for running a sex trafficking ring from 2002 to 2005 both in New York and at his estate in Palm Beach, Florida.

“With the evidence available more than a decade ago, federal prosecutors insisted that Epstein go to jail, register as a sex offender and put the world on notice that he was a sexual predator,” Acosta wrote of Epstein on Twitter. “Now that new evidence and additional testimony is available, the NY prosecution offers an important opportunity to more fully bring him to justice.”

Acosta also defended his decision to strike a deal with Epstein at his 2017 confirmation hearing, saying, “At the end of the day, based on the evidence, professionals within a prosecutor’s office decide that a plea — that guarantees that someone goes to jail, that guarantees that someone register generally and that guarantees other outcomes — is a good thing.”

Many critics have said this apology is not enough and that Acosta must resign immediately for the role he played in the case surrounding the billionaire. According to several reports, many of Epstein’s victims weren’t notified of his lenient sentence.

Other lawmakers who have called for Acosta to step down as labor secretary are Sens. Kirsten Gillibrand (D-New York), Tim Kaine (D-Virginia) and Ted Cruz (R-Texas) and Rep. Debbie Wasserman-Schultz (D-Florida).

Epstein could face up to 45 years in prison if convicted of both sex trafficking and conspiracy to engage in sex trafficking of minors.