Fighting back against a defamation lawsuit, Alan Dershowitz filed one of his own against a Jeffrey Epstein accuser who claims she was forced to have sex with the former Harvard law professor.

The counterclaim filed Thursday in New York federal court lists counts of defamation and intentional infliction of emotional distress against Virginia Giuffre, one of the first women to publicly accuse Epstein of sex trafficking.

Giuffre's suit filed in April claimed Dershowitz aimed to damage her credibility with news media by calling her, among other things, a "serial liar" and "prostitute."

Dershowitz, who has repeatedly denied having sexual contact with Giuffre, has long maintained her suit was an extortion plot, and he made clear in recent weeks that he planned to seek damages.

Dershowitz's counterclaim said the allegations were part of a "broader conspiracy" between Giuffre and her lawyers to "subvert the judicial process" to drum up private settlements from other wealthier individuals associated with Epstein, the late Palm Beach financier who died by suicide in a New York jail little more than a month after he was indicted on federal sex-trafficking charges.

"Her lies concerning Dershowitz have caused tremendous damage to his personal and professional reputation, his business, his health and caused him emotional and physical pain and suffering. Through these counterclaims, he seeks to hold her accountable for that damage," his attorneys, Howard Cooper of Boston-based Todd & Weld and Imran Ansari of New York-based Aidala Bertuna & Kamins, wrote in the 37-page submission.

Chuck Cooper of Washington-based Cooper & Kirk, who represents Giuffre, did not return a call for comment by deadline.

A Manhattan federal judge last month allowed Giuffre to proceed with her suit against Dershowitz but disqualified her longtime attorneys from Boies Schiller Flexner based on Dershowitz's plans to call firm chairman David Boies and Fort Lauderdale partner Sigrid McCawley to testify at trial.

Their continued representation would violate the witness-advocate rule, which bars attorneys from participating in cases where other lawyers from their firm might be called as witnesses, U.S. District Judge Loretta A. Preska of the Southern District of New York ruled.

Boies and McCawley say they will continue to represent Giuffre in other matters.

Both sides are due in court Nov. 13 for a case conference before Preska.

Epstein died by suicide Aug. 10 at a New York federal jail, but relatives are disputing the medical examiner's conclusion, pointing to homicide as a possibility. He was detained on sex-trafficking charges after avoiding federal prosecution in Florida in exchange for a Palm Beach County plea deal in 2008 allowing him to stay out of jail for much of a lenient sentence.

The Miami Herald published a series last year detailing allegations about Epstein that included dozens of women and specific allegations leveled against Dershowitz by Giuffre, one of the first women to comer forward against Epstein.

This year's indictment charged Epstein as a serial sex trafficker of "dozens of minor girls" at his mansions in Palm Beach and New York.

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