US entertainer Bill Cosby's lawyers are set to argue that prosecutors are reaching back to the "casting couch" era to round up female accusers and build a "stale" sexual assault case against him.
Before a Pennsylvania judge, they will challenge sexual misconduct claims over Cosby stretching from the 1960s through to the 21st century.
Cosby will be present for the hearing at the Montgomery County Courthouse.
Prosecutors will ask the judge to let 13 other women testify at the scheduled June trial that they were drugged and molested by Cosby in what they claim is his "signature" fashion.
Defence lawyers said the women's memories have been compromised by time and widespread media coverage of the case.
"The fact that even the most fervently held memories can actually be tainted - or altogether false - is supported by a vast existing and growing body of science," lawyers Brian McMonagle and Angela Agrusa wrote.
The pretrial hearing is expected to last two days, with another hearing on the evidence set for December.
Cosby, who is now 79 and legally blind, remains free on bail. It has been a half a century since the comedian became the first black actor to star in a primetime TV show, I Spy, and more than 20 years since his top-ranked sitcom The Cosby Show stopped filming.
After a Temple University employee made a sexual assault complaint against Cosby in 2005, prosecutors said there was not enough evidence to charge him.
But a new prosecutor, district attorney Kevin Steele, reopened the Montgomery County case last year amid new evidence: the scores of public accusers and a newly unsealed deposition which showed Cosby acknowledging he gave Andrea Constand three unlabelled pills and some wine before putting his hand down her pants.
Ms Constand, then 30, said she was only semi-conscious after taking what she thought were herbal pills. She had met Cosby through her job and said she went to his house that night for career advice.
Ms Constand settled a lawsuit against Cosby in 2006. The star's defence said her accounts of her relationship with Cosby changed in her initial police statements, and added that the two had been intimate before.
They also took aim at prosecution claims that Cosby attacked vulnerable young women in "signature" fashion after offering to mentor them.
Defence lawyers challenge the point, saying the women had different types of friendships with Cosby, met him in different cities and were various ages. The defence will ask Judge Steven O'Neill to bar their "prior bad act" testimony.
"Even if proven (and it could not be), the age-old 'casting couch' is not unique to Mr Cosby, and thus not a 'signature' nor a basis for the admissibility of these witnesses' stories, let alone a conviction," Cosby's team wrote.
The judge has so far sided with prosecutors in refusing to dismiss the case.