When police stop an active shooter they are doing their job. They are paid a salary to respond and resolve the conflict at hand.
We don’t really have a name for what it is called when a bystander interferes with the gunman (or woman). Perhaps they are doing their civic duty. But this word implies an obligation to react. I don’t think must people *expect* bystanders to put themselves in harms way.
Furthermore the bystander receives no monetary compensation. It’s not like there’s a standing bounty for anyone to grab if they stop a crime. When ordinary citizens give their time, skills and efforts to reduce public safety, what do they get?
Because whether a bystander or the police stop an active shooter the benefit to the nearby neighbors is the same. So you’d think we’d have a name for something so valuable.