He spends a night in jail, banned from the stadium for life, charged with criminal mischief. He's got a fine to pay, it's up to $5000, depends what the judge decides.
Criminal mischief is a charge where you have to apply for a pardon after 2 years, basically you get a record and you'll have a hard time travelling and getting jobs/whatnot.
Kid was 17 though, so if you're under 18 I dont think the charges stick as if you were charged as an adult.
Still a pain in the a.ss though, the worst part for this kid is the ban for life.
Jays games, UFC events at the Skydome/Rogers Centre are a lot of fun.