On Dec. 30, Montgomery County District Attorney Kevin Steele announced he was charging Cosby, 78, with aggravated indecent assault for the alleged January 2004 drugging and sexual assault of former Temple University employee Andrea Constand at his Cheltenham, Pennsylvania, mansion.
Todd Korol / Toronto Star / Getty; Gilbert Carrasquillo / WireImage
So far more than 50 women have accused Cosby of drugging and/or sexually assaulting them (which Cosby denies) but he has only been charged in Constand's case. Lawyers representing many of the women say they expect they will testify if asked. Cosby and his representatives have denied all of the allegations.
For more on the charges against Bill Cosby, pick up this week's issue of PEOPLE, on newsstands Friday
The Legal QuestionsLegal experts say both sides will have their challenges in court.
Rich DeSipio, a Philadelphia criminal defense attorney and former sex crimes prosecutor in Montgomery County, believes the key issue is whether any of the 50-some other alleged victims are allowed to testify as witnesses.
"It’s one thing for a jury to hear one woman say 'I drank some wine, took a pill, and was sexually assaulted against my will,' " he tells PEOPLE. "It’s a whole different ball game to hear that from 10, 25, or 50 women. "
The testimony could be allowed in under what's known as "other acts evidence" in Pennsylvania; its admission is up to a judge.
"It's a pattern of behavior to show his [alleged] plan in committing a crime – to show this is how he commits sexual assaults," explains DeSipio, who used the rule many times while prosecuting sex crimes in Philadelphia and in Montgomery County.
Because the testimony is potentially so prejudicial to a defendant, there has to be striking similarities to the alleged victim's case, says DeSipio.
Montgomery County Sheriff
"If something in any one of them is so dissimilar from the current case it isn't going to be admitted," DeSipio says. "Just alleging someone was sexually assaulted would not be admitted. It doesn't have to be identical but pretty close to it."
The rule is used a lot in sexual assault crimes, says DeSipio.
"Judges are more likely to let this testimony in in sexual assault cases than they are in other types of crimes because usually there's no other evidence," he says. "It's by nature a secret crime. It's her word against his. There's not going to be any physical evidence – no DNA, no forensics, no evidence of pills. And usually someone who commits a sex crime doesn't do it just once."
DeSipio believes the case will sink or swim on whether other alleged victims will be allowed to testify.
"I think if it's just the one victim it's a not guilty," says DeSipio. "If other victims are allowed to testify, he'll be found guilty."
Timing of Constand's AllegationsThe prosecution will also likely have to explain why Constand, now 42, continued to see Cosby after he'd twice come onto her, and also why she waited a year before going to authorities.
"Delayed reporting makes any claim of sexual assault – or for that matter, most crimes – difficult to prosecute," says Joe McGettigan, who successfully prosecuted former Penn State defensive coach Jerry Sandusky for sexually abusing ten young boys and is now of counsel with McAndrews Law Offices in Berwyn, Pennsylvania.
"On the other hand, you're now able to put on expert testimony about the reasons for delays," he tells PEOPLE.
After the Sandusky case, a new Pennsylvania law was enacted allowing expert testimony regarding victim behavior to be used in sexual assault cases, McGettigan says.
"They are allowed to say sometimes because of fear, shame or other psychological responses victims sometimes do not immediately make what's called a prompt complaint or an immediate outcry," says McGettigan, who was a local, state and federal prosecutor for more than 20 years.
"Nor are they allowed to offer an opinion about the ultimate credibility of the victim in a particular case," he says.
Scott Berkowitz, founder and president of Rape, Abuse & Incest National Network, or "RAINN," says "it's not uncommon" for there to be some delay in reporting in sexual assault cases.
"Obviously that makes it harder for police and prosecutors to prove a case but the fact that prosecutors are moving forward suggests there's other evidence there that proves what's being alleged," he tells PEOPLE.
"Prosecutors don't like to lose," he added, "and my strong guess is they wouldn’t have taken this step unless they thought they had a really compelling case to take to a jury."
Matt Rourke / AP
"I tried rapes cases before DNA existed so it was almost always 'he said, she said,' " he says. "If the jury thought the victim was credible they'd convict."
McGettigan, who knows all the attorneys on both sides of the case but has not spoken to any of them about it, says he'll be watching this closely.
"The thing I think will be most interesting about the case is I think there are a lot of really smart lawyers," he says.
"Kevin Steele knows what he's doing and I have the highest possible opinion of [Cosby's defense attorney] Brian McMonagle. He's good in front of juries. He's smart. He stays within the lines. He does things right."