NORRISTOWN, Pa. (Reuters) - A judge should allow 19 women to testify about alleged sexual abuse by comedian Bill Cosby to show a long-running pattern of “bad acts” to a jury at his retrial on charges of drugging and assaulting a former friend, a prosecutor said on Monday.

“He did it 19 times before he did it to Andrea Constand,” Assistant District Attorney Adrienne Jappe said, referring to the woman who has accused Cosby of sexual assault at the TV star’s home near Philadelphia between Dec. 30, 2003, and Jan. 20, 2004.

Cosby, wearing a tan sports jacket and tie, and smiling at times during the proceedings, has repeatedly denied wrongdoing, saying that any sexual encounter was consensual.

Jappe argued for the testimony by the other women during the hearing in Norristown, Pennsylvania, where his retrial is scheduled to begin with jury selection on March 29.

Cosby’s first criminal trial ended in a mistrial in June when jurors failed to reach a unanimous verdict in the same court.

Before the first trial, prosecutors asked Judge Steven O’Neill to allow 13 of the 19 women to testify against Cosby, but he allowed only one to do so because, in general, a defendant’s history is not admissible as evidence that he or she committed a particular crime.

But the Cosby case qualifies as an exception, Jappe told Judge O’Neill on Monday, because the way he abused the 19 women was so repetitive and consistent.

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“You’re going to see that all of these instances have shared similarities,” Jappe said.

For two hours, she detailed those similarities and cited a legal rule of evidence known as the “Doctrine of Chances,” which maintains that the more comparable crimes a suspect commits, the less likely it is that the next alleged victim is inventing her story.

Defense arguments to bar the 19 other accusers from the witness stand at retrial were slated for Tuesday, when the pretrial hearing resumes.

O’Neill said that due to the volume of evidence he must review, it was doubtful he would decide on Tuesday whether to allow testimony from the 19 additional accusers.

He said it was possible he could rule on Tuesday on a defense request to call as a witness at trial a former co-worker of Constand who had told prosecutors that Cosby’s accuser said she could earn money by making a false sexual assault allegation against a famous person.

Best known for his television role as the wise and witty father in “The Cosby Show,” Cosby has been accused of sexually assaulting more than 50 women over several decades. The Pennsylvania case is the only one in which he has faced criminal charges.