Usually the City Police Chief is changed when mayors are changed, they are mayor appointees. Especially if the party in charge changes. Even then that is not a reliable fact, the mayor will want his OWN crony in the position. They are trying to make it a sexual orientation one to stop the change the mayor wants.
A county Sheriff Chief is usually elected.
It doesn’t matter the career field, if you attempt to undercut your boss and are unsuccessful, it will not be good for you.
From Godfather II.
Frank Pentangeli: Those were the great old days,you know... And we was like the Roman Empire... The Corleone family was like the Roman Empire...
Tom Hagen: When a plot against the Emperor failed... the plotters were always given a chance... to let their families keep their fortunes. Right?
Frank Pentangeli: Yeah, but only the rich guys, Tom. The little guys got knocked off and all their estates went to the Emperors. Unless they went home and killed themselves, then nothing happened. And the families... the families were taken care of.
Tom Hagen: That was a good break. A nice deal.
Frank Pentangeli: Yeah... They went home... and sat in a hot bath... opened up their veins... and bled to death... and sometimes they had a little party before they did it.