When I was a teenager fistfights were a fairly common occurrence, even among kids who would consider themselves good friends and often for reasons that couldn’t be articulated later. A fistfight isn’t the same as a stabbing, but a fistfight is closer to a stabbing than it is to nonviolence. Our brains just aren’t finished yet. I’m not saying that at 16 someone shouldn’t be able to understand that stabbing someone for almost any reason is wrong, nor am I saying this person shouldn’t be held to account in some way. I’m just saying that if you’re asking “why?” sometimes the answer is gonna be “We’re fucked up, some of us more than others.”