Note: This episode contains descriptions of sexual violence. A former Senate aide to Joseph R. Biden Jr., the prospective Democratic presidential candidate, has accused him of sexually assaulting her in 1993. A Biden spokeswoman said the allegation was false, and people who had worked in Mr. Biden’s office did not recall talk of such an incident. Today, we examine what we know about the allegation, who Ms. Reade spoke to about her experience at the time and what her former colleagues say now. Guest: Lisa Lerer, a reporter at The New York Times who covers campaigns, elections and political power, who spoke with Ms. Reade. For more information on today’s episode, visit nytimes.com/thedaily.  Background reading: Ms. Reade recently filed a report with the Washington, D.C., police, saying she was the victim of a sexual assault in 1993. While not naming Mr. Biden directly, Ms. Reade said the complaint was about him.Last year, Ms. Reade and seven other women came forward to accuse Mr. B...