"They treated her like a toy," prosecutor Marianne Hemmeter said.
Prosecutors argued that the victim was so intoxicated she couldn't consent to sex that night, while the defense contended the girl realized what she was doing and was known to lie.
The girl testified that she could not recall what happened but woke up naked in a strange house after drinking at a party.
"It was really scary," she said. "I honestly did not know what to think because I could not remember anything."
She said she believed she was assaulted when she later read text messages among friends and saw a photo of herself naked, along with a video that made fun of her and the alleged attack.
Three other boys, two of them on the football team, saw something happening that night and didn't try to stop it but instead recorded it with their cellphones. Granted immunity to testify, they confirmed the girl was assaulted and said she was so drunk she didn't seem to know what was happening.
Evidence at the trial also included sexually explicit text messages sent by numerous students after the party. Lawyers noted how texts have seemed to replace talking on the phone for young people. A computer forensic expert documented hundreds of thousands of texts found on 17 phones seized during the investigation.
In sentencing the boys, Lipps urged parents and others "to have discussions about how you talk to your friends, how you record things on the social media so prevalent today and how you conduct yourself when drinking is put upon you by your friends."
After the arrests, the case was furiously debated on blogs and social media, with some people warning of conspiracies and conflicts of interest. On Sunday, Hemmeter, the prosecutor, criticized efforts by the hacker collective Anonymous to publicize the case, saying the attention had a chilling effect on those willing to testify.
After the verdict, the accuser's mother rebuked the boys for "lack of any moral code."
"You were your own accuser, through the social media that you chose to publish your criminal conduct on," she said. She added that the case "does not define who my daughter is. She will persevere, grow and move on."
Echoing that, the judge said that "as bad as things have been for all of the children involved in this case, they can all change their lives for the better."