A US judge has refused to throw out a libel suit filed by three women against Bill Cosby the same day the comedian was set to testify in a separate molestation case.

In a 38-page ruling posted online by the Hollywood Reporter, Judge Mark Mastroianni of the US District Court in Springfield, denied Cosby’s motion to dismiss the suit filed by the three women.

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The women say Cosby sexually assaulted them years ago, then called them liars when they went public with their accusations last year.

The decision is the latest legal setback for Cosby, 78, coming on the same day he was called to testify under oath in a Los Angeles lawsuit accusing him of drugging and sexually molesting a 15-year-old girl.

The woman, now 57, says Cosby assaulted her at the Playboy Mansion in Los Angeles in 1974.

She filed suit against him in December amid an outpouring of similar accusations by dozens of women against the former TV dad.

Since November, more than 40 women have publicly accused Cosby of sexual assault.

Most have said the attacks took place after Cosby covertly slipped them knockout drugs. The alleged incidents span four decades starting in the mid-1960s.

Through his lawyers, Cosby has called the 57-year-old’s lawsuit “frivolous” and accused her of extortion. A judge on Wednesday refused to dismiss it.

Cosby himself has not commented publicly on the accusations and has never been charged with a crime.

In a 2005 civil suit for sexual assault that was later settled out of court, he admitted procuring sedatives in the 1970s to use on women he wanted to seduce but insisted the encounters were consensual.

Friday’s deposition is the first time Cosby has been forced to testify under oath since the most recent accusations.

Plans for the questioning were shrouded in secrecy, with neither side disclosing the time or location or confirming it had taken place at all.

Janice Dickenson, a 60-year-old former supermodel who says Cosby assaulted her in 1982, has also sued him for defamation in California.