Just today a student was suspended for tackling and disarming another student on the school bus who'd pulled out a gun and was about to shoot one of the other passengers. The school said he was "involved" in an incident with a weapon, so they suspended him. With that logic all the police officers should be in jail for being "involved" in an arrest.
As for the student with the ringtone, did the police verify that he wasn't infringing on the copyright to the song? Since he was allegedly the one singing it, he's probably not paid into any royalty stream and thus could possibly face huge fines and jail time. He's lucky the police didn't find any nail clippers or they could probably add on "armed copyright infringement" and slap another five years on his sentence.