Damaging testimony that Bill Cosby gave in an accuser's lawsuit, including admissions that he gave young women drugs and alcohol before sex, can be used at his criminal sex assault trial, a judge ruled Monday.

Bill Cosby's eyesight has deteriorated to the point where he can no longer identify his accusers in photographs or otherwise help with his own defence, his lawyers argued Wednesday.

Cosby is facing charges about a single 2004 incident, but prosecutors hope these 13 women can prove a distinct criminal pattern.