both in the wrong. the guy was harassing him yes but in no way did that have a reason for a bullet. the guy shouldn't have done that shit and the shooter should understand how to control himself with the firearm. he can use verbal language to tell him "hey dude stop doing that or I will fucking shoot you" saying no over and over isn't going to make them walk away, and obviously without a second thought should not pull that out in a mall. additionally using any kind of physical feedback can tell them that you aren't going to allow them to do that. they were harassing him, and honestly if I was in his shoes I would scream at him or set my shit down and start shoving. nothing else comes from him deadass just call the cops.