Bill Cosby goes back to court in April, but his retrial on sexual assault charges will unfold in a very different America than his first.

Since then, the #MeToo movement has established that women who individually once feared their accusations would be discounted or dismissed can find corroboration and power when they come forward as a group.

Though more than 50 women have accused Mr. Cosby, once among America’s most beloved entertainers, of drugging and sexually assaulting them, only two were permitted to to tell their stories in a Pennsylvania court in the first trial, which ended last summer with a hung jury.

But prosecutors on Thursday asked the judge handling the case to reconsider his limits on such testimony in the hope that the accounts of 18 more women would help support the accusations by Andrea Constand, the former Temple University staff member who says Mr. Cosby assaulted her at his home outside Philadelphia in 2004.