Actress Katherine MCKee, who appeared on The Bill Cosby Show in 1971, came forward with her sex assault allegations last year (Dec14), claiming the actor attacked her at a hotel in Michigan back in the '70s, while she was dating the legendary singer.

She alleges the incident happened after she agreed to pick up some ribs for his dinner and deliver it to his room, where Cosby is said to have greeted her wearing a bathrobe before attacking her.

She never told Davis, Jr. about what happened because she was so ashamed, explaining to the New York Daily News, "I never said a word. I was too uncomfortable about it... I didn't want to put that in Sammy's head. I was mad at my own self for not saying, 'What the f**k?' Why didn't I stop it and get him away from me?' But it happened too fast. I was absolutely flabbergasted. And I had the guilt. I questioned myself, 'Why did I go there? Why did I bring him those ribs? Maybe he thought that's what I wanted too...'

"It was a rape, but it seemed so strange to call it that. We think of rape as a stranger who attacks you in a parking lot. I chalked it up to another powerful person in Hollywood who just felt he could take what he wanted from women."

Cosby's lawyer dismissed the accusation as a lie following its original publication, and as the statute of limitations on her rape claim has long expired, MCKee has decided to take the star to court for defamation, reports TMZ.com.

MCKee is the latest alleged victim to sue for defamation - last week (ends18Dec15), Cosby launched a countersuit in Massachusetts against a group of seven women who accused him of sexual misconduct, only to have their accusations shot down and their credibility questioned.

On Monday (21Dec15), Cosby also slapped his own defamation suit against former supermodel Beverly Johnson, who maintains he tried to drug her during an encounter in the 1980s. He is fighting back against the accusations, with his Los Angeles lawyers disputing Johnson's account as "false, malicious, opportunistic, and defamatory".

More than 50 women have gone public with decades-old claims of inappropriate behaviour against Cosby in the past 14 months. The TV star, who has never been charged with any crime related to the counts, has denied all accusations.