Yeah, I don't believe police is acting in good faith, and I believe that both Breonna Taylor and George Floyd demonstrates that fairly well, in one case the police got a warrant for the wrong apartment, seemingly on purpose, did a no knock raid and killed someone. In the case of Floyd the officers needed to handcuff a man pushed to the ground, not kneel on him for nearly a dozen minutes.
The police didn't even act in good faith in the case where they just left, they decided not to do their job because they created some twisted binary in which nothing was done or someone was killed. That is acting in bad faith.
And yet we're only now hearing of a grand jury being convened in the case of Taylor, and while we got to it sooner with Floyd that was only after massive public outcry.
So no, what I describe isn't what is happening, because investigation is squared away within the police departments, and even when someone is fired they can move to a different department and get a job as an officer.
Investigations need to begin sooner, they should not be performed by police, and resulting measures should not be circumventable.