(CNN) A federal judge in Florida ruled that the Department of Justice broke the law by failing to confer with victims of Jeffrey Epstein, a well-connected Palm Beach billionaire and alleged serial sex abuser of underage girls, about the 2008 plea deal that garnered him only 13 months in prison and no federal trial.

Judge Kenneth Mara issued the ruling Thursday as part of a years-long lawsuit brought by victims of Epstein identified only as Jane Does. However, the ruling does not address what remedy, if any, the plaintiffs are entitled to going forward nor the legality of the plea deal itself.

In November, the Miami Herald reported that when Labor Secretary Alexander Acosta was a US attorney in Florida, he gave Epstein the "deal of a lifetime." In a sweeping review of the politically connected billionaire's case, the Herald explained how Acosta had made an agreement with Epstein to avoid major repercussions for the hedge fund manager, even though a federal investigation had identified 36 underage victims.

The report said Acosta had brokered a deal with one of Epstein's attorneys where he pleaded to two state prostitution charges, ultimately serving only 13 months and avoiding a federal trial. He also registered as a sex offender and paid restitution to the victims identified by the FBI.

The agreement, the Herald said, "essentially shut down an ongoing FBI probe" and further granted immunity to "any potential co-conspirators" in the case.

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