https://www.theatlantic.com/national/archive/2011/07/many-federal-employees-more-likely-die-be-fired/353024/
I doubt it's much different at the local level.
I'd also like to point out, I have routinely called for police to quit the thin blue line mentality and remove the drunks, druggies, racists, excessive force, thieves, dregs from their ranks.
The old days of covering up for partners, police failures is gone.