[keat]

Tragic story but I'd be digging a little deeper for all the facts. Seems unlikely that one could choke oneself to death by direct pressure. You would pass out, pressure would be released, and you would regain consciousness soon.

To do it by accident? Doesn't seem possible unless the chain were long enough to lock around your neck.

[Valpal1]

Perhaps he was playing at self strangulation to get a rush. This is becoming a phenomenom in the grade school set.