By Oliver Gettell
Updated November 13, 2015 at 09:56 PM EST
David A. Smith/Getty Images

Four women who have accused Bill Cosby of sexually assaulting them joined a federal defamation suit against him, alleging that he let his representatives falsely brand them as liars after they came forward.

In an amended complaint filed on Friday and obtained by EW, Barbara Bowman, Joan Tarshis, Louisa Moritz, and Angela Leslie join the three women who previously brought the complaint in Massachusetts. The women cannot sue Cosby for the alleged sexual assaults because of the statute of limitations.

“They’re trying to restore their good name and reputation that was allegedly taken away from them by Mr. Cosby,” said attorney Joseph Cammarata, who filed the amended complaint.

Cosby, 78, now faces allegations of defamation from 10 women in a total of four cases, including one in California, one in Pennsylvania, and a second case in Massachusetts filed earlier this week.

More than 50 women have accused Cosby of sexually assaulting them, in many instances after plying them with drugs or alcohol. He has maintained his innocence and has never been charged with a crime.

In the California defamation case, brought by model Janice Dickinson, an appeals court on Thursday temporarily stayed an order requiring Cosby and his former attorney Martin D. Singer to face questioning under oath this month.

A representative for Cosby declined to comment on the four women joining the defamation suit.