The key is if you are in a place with a bunch of teen males you should be automatically suspicious. If I see four white kids on the walking trail by my house, I am watching them closely until we pass, and after. I mean I am polite, and all, say “hey guys, what’s up” it’s just that I am looking the group over to make sure they seem ok. It’s just how I roll right or wrong…
Similarly if there is a group of black teen males you should be even more suspicious because the rate of violent crimes amongst that demographic group is an order of magnitude higher.. You should have a sixth sense not to go walking into crowds like this. Not saying this guy deserved it at all. Just saying I would probably not walk into a big group like that.