(STEUBENVILLE, Ohio) -- Prosecutors in a closely watched trial beginning Wednesday in Steubenville, Ohio, opened their case against two high school football players by describing a night of partying that went awry when the teens allegedly sexually assaulted a girl who was "stumbling, her speech was beginning to slur, losing her balance."
As the alleged victim, a 16-year-old from West Virginia, was driven from party to party Aug. 11 after becoming intoxicated and "substantially impaired," the boys -- Ma'lik Richmond, 16, and Trenton Mays, 17 -- took more and more liberties with her, prosecutor Marianne Hemmeter said Wednesday in court.
"This case will hinge on not only the defendants' knowledge of her substantial impairment but their exploitation of that knowledge when they treated her like a toy on Aug. 12, 2012," she added.
Mays is also charged with distributing child pornography for texting images of the girl.
The "degradation continued," Hemmeter said, when two photos of the victim circulated on social media, first through the school and then across the Internet. At least one of the photos was initially sent from Mays' cellphone, leading to the additional child-pornography charge against him.
The boys are on house arrest, attending school at a juvenile-detention facility. They are being tried in a juvenile court and if found guilty could serve time until they turn 21.
Both boys have denied the charges. Richmond's lawyer declined to make an opening statement.
But he has told ABC News' 20/20 that what occurred that night was consensual.
Brian Duncan, a lawyer representing Mays, said simply: "Trent Mays did not rape the young lady in question."
In an exclusive interview recently with 20/20 anchor Elizabeth Vargas, Richmond said, "I didn't rape anybody. I didn't witness a rape going on."
"And if I would have thought that somebody was being raped or anything like that, I would have stopped it."
The case drew international attention after photos of the young woman spread via social media and questions were raised about why more students who witnessed the alleged assault were not charged.
The case drew further attention when some outside the small Rust Belt town accused local officials of willfully protecting the football players, seen as hometown heroes.
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