Jury selection begins Monday in a criminal trial against comedian Bill Cosby on felony charges of sexual assault — and just a few hours into the process, it's evident that seating a jury is going to be a challenge.

Out of 100 potential jurors questioned on Monday morning, one-third said they'd already formed opinions about Cosby's innocence or guilt, more than a third said they or someone close to them had been the victim of sexual assault, and a full two-thirds of possible jurors said serving for the lengthy trial would be a hardship for them, Mark Nootbaar of member station WESA reports.

"When asked who had heard about the case, 86 [people] raised their hands," Nootbaar said.

The case is being heard in a suburb of Philadelphia, but jury selection is taking place in Pittsburgh because of the massive publicity the case received in its home district, Nootbaar reports.

"Jury selection is expected to take several days," he reports, "with hundreds of potential jurors being questioned."

Images from outside the courthouse in Pittsburgh show photographers surrounding Cosby as he walked toward the building, using a cane.

Cosby indicated last week that he doesn't plan to testify in this trial.

More than 50 women have publicly accused Cosby of rape or sexual assault. Many of them described the comedian promising mentorship or advice, plying them with pills or drinks and molesting or raping them while they were drugged.

But the statute of limitations has expired on most of those allegations. The current case, in Pennsylvania, is an exception. The alleged assault occurred in 2004, and the charges were filed just within the 12-year limit.

The story of how the case came to be filed is a lengthy saga, involving a civil case that ended in settlement, and an explosive deposition unsealed at a journalist's request.

Bobby Allyn of member station WHYY has a full explanation of what happened.

But in brief, Andrea Constand, who used to work with the Temple University women's basketball team, says Cosby drugged her and touched her sexually, without her consent, after she came to his house near Philadelphia for what she thought would be a conversation about her career.

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