Skateboard to the head can kill a person. Skateboards have metal on the underside with a bolt sticking out. If that bolt connects with a persons head it can kill them.

They both had skateboards and they both were stealing. I watched the video. Solution to this problems seems clear to me. Don't steal. And don't swing skateboards at cops. They could have dropped the skateboards and turned themselves in but I'm guessing they choose to thug it out.

edit: they shouldn't have tried to steal, what looks to be, beer. Get job, get money, then go to the store and buy things.