Alan Dershowitz has filed counterclaims for defamation and intentional infliction of emotional distress against a Jeffrey Epstein accuser who has claimed she was forced to have sex with the former Harvard law professor.

The counterclaim was filed late Thursday in the U.S. District Court for the Southern District of New York in litigation begun by Virginia Giuffre when she sued Dershowitz for defamation in April. Giuffre claimed Dershowitz aimed to damage her credibility with the media by calling her, among other things, a "serial liar" and "prostitute."

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

Dershowitz' counterclaim said the allegations were part of a "broader conspiracy" between Giuffre and her lawyers to "subvert the judicial process" in order to drum up private settlements from "other, wealthier individuals associated with Epstein, the late Manhattan and South Florida-based financier who killed himself earlier this year while awaiting trial 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 City-based Aidala Bertuna & Kamins, wrote in the 37-page submission.

Chuck Cooper, of Washington-based Cooper & Kirk, who now represents Giuffre in the litigation, did not return a call Thursday evening requesting comment on the allegations.

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' plans to call firm chairman David Boies and partner Sigrid McCawley to testify at trial.

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

While Cooper has taken over as Giuffre's attorney in the defamation case, Boies and McCawley say they will continue to represent her in other matters.

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