I think it is highly unlikely that any of his actions would result in any significant jail time. Community service, a fine, and/or some sort of probation are all more likely.

I had a childhood friend who got in with a bad crowd in high school. At some point, when he was about 17, he was caught illegally entering a business at night. His parents refused to go pick him up from the police station, so he had to spend the night and most of the next day in a cell. I don't believe his ultimate punishment involved any jail time.

I respect his parent's decision. That sort of action teaches a troublesome kid that there are real consequences for breaking laws beyond just upset parents. While a criminal record might make it harder for him to get a job in the future, it certainly doesn't make it impossible. I also suspect it is better than letting a kid think that other people will protect him and he can get away with whatever he wants.