TAMPA — A 16-year-old girl told police two years ago that she was raped at a University of South Florida fraternity party.USF police arrested Dillon LaGamma, who was then a 19-year-old sophomore and a member of the Pi Kappa Phi fraternity, on a charge of sexual battery.Since then, the case against him has moved quietly through the court system.Until a few weeks ago, when it was quietly dropped.Prosecutors this week offered little explanation, except to say they weren't confident they could convince a jury of his guilt."With the evidence we had, we realized we couldn't prove the charge beyond a reasonable doubt," said Estella Gray, a spokeswoman for the Hillsborough State Attorney's Office. LaGamma's defense attorney, Michael Orenstein, declined to discuss the specifics of the case. He said LaGamma is now taking college classes in Broward County."He felt terrible about the whole thing," Orenstein said. "It was a horrible experience and he feels for everyone involved."LaGamma, now 21, was scheduled to go on trial Dec. 3. The state filed a notice that they would no longer pursue the case Nov. 9.While the criminal case is over, a lawsuit filed by the victim and her parents is still pending. They are seeking more than $5 million in damages against LaGamma, the Pi Kappa Phi fraternity and 12 individual fraternity members."I see a lot of cases that don't get prosecuted because it's a higher burden of proof," said Jeff Herman, the Boca Raton lawyer representing the victim.In criminal court, the state must prove its case "beyond a reasonable doubt," meaning with virtual certainty that the defendant is guilty. The burden is much less in civil cases, where the plaintiff must prove their case by a "preponderance of the evidence," meaning it's more likely than not that a defendant is responsible for an alleged wrong."That's why the civil case is important because it's the only measure of justice for this," Herman said.The lawsuit complaint offers an account of what the plaintiff says happened Oct. 1, 2016 at the Pi Kappa Phi house in USF's Greek Village. Before the party that night, the complaint alleges, fraternity members obstructed the video surveillance cameras at the house. Fraternity members set up a table outside to make it appear they were checking the identification of party goers, the complaint states.The victim and her two older sisters entered the party, where they were given alcoholic beverages, according to the complaint. At one point, a fraternity member encouraged the girl and her sister to drink from a "slap bag," which is a bag filled with a potent alcoholic beverage, the complaint states.The girl became "dangerously intoxicated," was incoherent and had difficulty standing, according to the complaint.The suit states that LaGamma took her to a room and had sex with her while she was unconscious. LaGamma said he believed she consented to having sex, according to the complaint. But the suit alleges that the girl was incapable of consenting because of her level of intoxication.A fraternity member later told the girl's sister she was unconscious and had to be taken to a hospital. The victim remembered waking up in the hospital with the bottom half of her clothes covered in blood, the complaint stated.Herman, the lawyer bringing the lawsuit, said the victim and her family are frustrated with the outcome of the criminal case but hopeful she can have a voice through the civil proceedings."She's having a lot of issues," Herman said. "This was devastating to her and her family."Contact Dan Sullivan at [email protected] or (813) 226-3386. Follow @TimesDan.