Jeffrey Epstein attends Launch of RADAR MAGAZINE at Hotel QT on May 18, 2005.

Patrick McMullan | Getty Images

The supervision that Jeffrey Epstein, now accused of child sex trafficking, received from jailers in Florida a decade ago is now the subject of an internal investigation on the heels of claims he had sexual contact with at least one young woman, authorities said Friday.

Epstein was allowed out of the Palm Beach County lockup for up to 12 hours a day on work release, six days each week, during his 13-month jail stint there after pleading guilty to prostitution-related charges filed by state prosecutors in 2008.

That cushy arrangement had already sparked outrage.

So had Epstein being allowed to cut a nonprosecution deal with federal prosecutors in Florida in 2007 that let him off the hook for potentially much more serious federal charges related to sexual misconduct with underage girls.

Earlier this week, a lawyer said Epstein, a former friend of Presidents Donald Trump and Bill Clinton, had “improper sexual contact” with at least one woman under the age of 21 in Epstein’s business office in West Palm Beach, Florida, during his work release, as Palm Beach sheriff deputies waited outside.

The lawyer, Brad Edwards, represents some of the women who claim they were sexually exploited by the now-66-year-old Epstein as underage girls from 2002 through 2005.

Their allegations and ones by other women led federal prosecutors in New York to charge Epstein earlier this month with child sex trafficking crimes.

After Edwards made his claim Tuesday, Palm Beach Chief Deputy Sheriff Michael Gauger told The Palm Beach Post newspaper that if what Edwards said occurred then, “That’s news to me.”

“That would shock me if the deputies allowed someone else in” to see Epstein, Gauger said, according to the Post.

Palm Beach Sheriff Ric Bradshaw on Friday “ordered an Internal Affairs investigation into the Jeffrey Epstein matter,” Bradshaw’s office said in a statement.

“Sheriff Bradshaw takes these matters very seriously and wants to determine if any actions taken by the deputies assigned to monitor Epstein during his work release program violated any agency rules and regulations, during the time he was on [the sheriff’s office] work release program.

“All aspects of the matter will be fully investigated to ensure total transparency and accountability,” the statement said.

Epstein earlier this month pleaded not guilty to the newly filed sex trafficking charges in U.S. District Court in Manhattan.

Prosecutors say he abused dozens of underage girls, some as young as 14, at his luxurious Upper East Side townhouse, and his Palm Beach mansion in the early 2000s.

Epstein allegedly had the girls visit him there under the initial pretense of giving him massages, and then would allegedly pay them hundreds of dollars after each session.

On Thursday, federal Judge Richard Berman denied Epstein’s bid to be released on bail of as much as $100 million, calling him a danger to the public, and a serious risk of flight given his fortune, which is estimated to be as high as $500 million.

“Mr. Epstein’s alleged excessive attraction to sexual conduct with or in the presence of minor girls — which is said to include his soliciting and receiving massages from young girls and young women perhaps as many as four times a day — appears likely to be uncontrollable,” Berman wrote in a scathing decision rejecting the bail request.

Trump’s Labor secretary Alex Acosta last week resigned after criticism of his cutting the federal nonprosecution deal with Epstein when Acosta was the U.S. attorney for Miami in 2007.

That deal required Epstein to plead guilty to the Florida state prostitution-related charges, and to register as a sex offender.

A lawyer for Epstein did not immediately respond to a request for comment.

— Additional reporting by CNBC’s Kevin Breuninger.