I agree with Rob that if you get out your gun, you should be prepared to use it.
That being said, before my department entered the 21st century and began carrying AR15s, we had Mossberg 12 gauge shotguns. Department policy prohibited us from carring a round in the chamber until we deployed the weapon.
Over the years, more than one suspect who wasn't taking commands to hit the ground seriously, got serious when they heard that racking noise.
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