I've been to a few weapons courses and have encountered a LOT of different folks from various backgrounds and professions. LE included.
French Special Ops guys, Marine Force Recon, Rangers, Army Spec Ops, SWAT, etc.
The Marines are always the most squared away individuals of any group I trained with, BTW.
The LE guys usually fall into one of two categories.
Very good....to very "ineffective". No real in between, it seems.
I went to Bill Rogers Shooting School a few years ago and got to train with some real high speed guys.
The guy that received the coveted "Bill Rogers" pin (highest score) was a beat cop.
His partner, I believe failed to qual.
No big sin there because Rogers Range is a humiliating, humbling, gut wrenching experience.
But, it does reveal a lot about the shooter.