A federal magistrate judge in Springfield recused herself Tuesday from a lawsuit that a Las Vegas woman filed the day before against embattled comedian Bill Cosby.

In a legal filing, Judge Katherine A. Robertson wrote, “I hereby disqualify myself in all proceedings related to’’ the lawsuit that Kathy McKee, 66, an actress and casting executive, filed Monday against Cosby, 78.

McKee is the eighth woman to sue Cosby in the Springfield court, and like the others, she alleges that he sexually assaulted her decades ago and defamed her in the press when she went public with her claims.

Robertson did not elaborate on her reason for recusing herself, but she previously worked in the Springfield firm of Bulkley, Richardson and Gelinas, LLP, the same firm that Cosby had hired to represent him in the other lawsuits. Cosby has stopped using the firm for the main litigation, but it is still listed as his counsel of record for a related insurance matter.

McKee, who is representing herself, alleges in her civil complaint that Cosby raped her in a Detroit hotel room in 1974.

“The rape was an unprovoked and violent attack,’’ the filing said. “The rape was shocking, scary, and horrible.’’

Cosby’s lawyers have not filed an official response to McKee’s lawsuit or responded to a request for comment. Dozens of women have accused him of sexual assault, but he has not been criminally charged and has denied wrongdoing through his representatives.

Like the other women suing him in Springfield, McKee says Cosby’s attorney maligned her in the press last year when she went public, calling her a liar and employing “artifice, fallacy, innuendo and inference’’ to cast doubt on her integrity.

Cosby recently filed a counterclaim for defamation against the seven other women suing him in Springfield. Trial dates have not been set.

In a related matter, Cosby’s wife, Camille, is fighting a subpoena from the other seven accusers, who are seeking to depose her.

Lawyers for the Cosbys on Friday filed a motion to quash the subpoena, calling the effort to depose Camille Cosby a “thinly veiled attempt to pressure [Bill Cosby] in the face of subjecting his wife to the shame and embarrassment of responding to questions about his alleged infidelities and sexual misconduct.’’

On Monday, lawyers for the accusers fired back, writing in court papers that “there is likely no single person, other than Mr. Cosby himself, who has more knowledge of Mr. Cosby’s sexual proclivities and encounters (consensual and nonconsensual), as well as his use of Quaaludes and other sedatives, than Mrs. Cosby.’’

Many of Bill Cosby’s accusers contend that he drugged them before sexually assaulting them.

In a 2005 deposition, he admitted that he obtained quaaludes in the 1970s to give to women he wanted to have sex with, but he denied giving the sedative to anyone without their knowledge. He called quaaludes “the drug that kids, young people were using to party with.’’

Material from the Associated Press and New York Times was included in this report. Travis Andersen can be reached at travis.andersen@globe.com. Follow him on Twitter @TAGlobe.