What are my rights if someone stole my freon to huff?

I have a son who during spring break made a friend and I met the friends mother seemed very nice. Then later I find out the boy had just come home from juvenal hall, and he was "huffing", plus breaking into homes. Not only upset the mother didnt tell me, I put a stop to him coming around. I still can't believe she wouldn't give someone a warning, my son had never heard of huffing until then. Well now its hot, so we go to use the air conditioner, the freon is empty, after questioning my son due to the talk of huffing, weeks prior he admits that his friend showed him and they did thihs. I know he would not have had the opportunity under normal cirstances but at that time my mother was ping away and we were at the hospital every night very late. I should have kept a closer eye I know. Can this kid who just turned 18 be responsible for the 300 dollar fee to have it refilled? I am so frustrated, and also to be safe, I put my son in an outpatient treatment that specializes in huffing and there is a test to detect it in the system, this is all expensive, that doesn't matter my son is worth it, but the other kid stole the freon, my son also said they used a very small amount, I would swear that kid has come to my home and used the rest after that. I hope someone has a solution or knows if I have any right to go after him.