I guess my only problem is from the wording in the article it doesn't seem like the dude made it clear to the bully that he had a knife. It says he showed it to people on the bus, but not necessarily the bully. It seems the kid was only hit one time, and then stabbed the guy until he was dead. Even considering the bully brought his friends with him, I don't see how lethal force was required here. I don't think the guy should get charged with murder or anything, but it does seem like this law is cruel towards the bully's family.