Most LEO's are lawful well intentioned, but they do stand by and cover for a good many who are not, those that these days have encrypted chat groups dehumanising those they interact with and swapping notes on what they can get away with and come out smelling of roses.
Those rotten apples corrupt new recruits and normalise harshly putting the boot in, curb stomping, and other extremes.
An acquaintance of mine has seen the full roller coaster over the past 45 years, first defending police that were unquestionably exuberant in violence, later shunned for having had enough and pulling the rug.