be criminal charges. He needs to fully understand the seriousness of the mistake he made so that he will never do something like that again. How he learns that lesson is best judged by his parents who know him best. It would be tragic if he never learned from this mistake and did something similar again which lands him a criminal record and derails his life.
It can be a fine line between a borderline largely harmless mistake and something far more serious. I have seen a number of cases where kids go from doing harmless things that are considered "kids being kids" to doing similar things as an adult which results in dire consequences because the person in question never learned the limit.