(CNN) -- Two Steubenville, Ohio, football stars sexually assaulted a 16-year-old girl, treating her "like a toy," a state prosecutor said Wednesday in the opening statement of the teens' rape trial. Trent Mays, 17, and Ma'lik Richmond, 16, are accused of sexually assaulting the girl at a series of end-of-summer parties in August, according to prosecutors. The case received widespread attention nationally after other Steubenville teens posted images of the alleged victim seemingly unconscious to social media sites. Defense attorneys say the boys are innocent of rape. Mays is also charged with illegal use of a minor in nudity oriented material.
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NEW: Witness says she and the alleged victim shared vodka at a party
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Trent Mays, 17, and Ma'lik Richmond,16, are charged with rape
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The boys are accused of sexually assaulting a girl at end-of-summer parties
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Football players bragged of what they did to a 16-year-old girl, a prosecutor says
"@placeholder did not rape the alleged victim, and the prosecution cannot and will not be able to establish and substantiate their claim," Duncan said.