Not an option you have if theres people between you and the shooter like a dense crowd, and firing through a crowd is general frowned upon, even when you’re trying to not hit them. The last thing you do if you have a gun in that situation is pull it out before you have cover and know where the threat is coming from or your will absolutely be shot by the cops if not the shooter. Dense crowding also played a part in why they were able to be tackled to the ground. A lot harder to get close if the shooting starts and no one’s physically near the shooter.