No charges
In the end, the boys had come up with a story before they arrived at the station and were determined to stick to it. They were not going to accept the responsibility for their actions, they were going to deny it for as long as they needed to. They made a firm choice.
When it was all said and done, the police had to let them go and they closed the case. But by that time the entire town had heard about what had happened and everyone knew who had done it. The boys were public enemy number one, even if they were not officially convicted of any crime.