I spect there are just some people you get in there that you quickly realize have no business carrying a firearm. EVER.
That one disqualified himself from carrying a screwdriver around live electrical equipment.
...stuck a big ol' GI screwdriver in a 400A bus bar, knocked himself across the room, popped half the circuit breakers in the place and cost us a half a day resetting things.
Never saw him around any firearms and really happy for it.
...woulda had to shoot the fool and I'd still be filling out paperwork.