I really don't think the guy was violent because he was under the influence...I think it just kinda messed him up, and then his parents were really pissed off at him, he started neglecting people, he started acting like a jackass...he got to a point where he was just overly frustrated. I think he drank some, too...he had a group of friends that I didn't know much. When I tried to have a serious talk with him, we started to argue...he eventually just attacked me. Completely flipped out. He was just...never like that before.

I don't know what exactly weed does to you directly...but I have good reason to believe that it helped change him for the worse.