I think it's unwise to compare "people in a church" to "as police". People in a church have just the same variety as people in any other public place, in the manner of mental and emotional qualities. Further, regardless of how "batman" any given person with a gun believes himself to be, if he isn't police, or ex police or military, there's a high likelihood he doesn't have the training or discipline associate with such. Of course you can cite isolated exceptions, but the exception to a rule doesn't, cannot, promote practice.
Also, this isn't including the issue police and military people do victimize each other. They do, but I will spare you details for the purpose of this.