I suppose the reasoning would go as follows;
Since cops are the Only Ones trained and competent enough, and with good enough judgment, to carry guns, anything they do that causes harm to innocents must therefore be someone else’s fault. QED. Move along. Nothing to see here. Relax and enjoy your shoes.
I’m all for wiping the personnel roster completely clean, right down to the janitor, in some departments, and starting over. It’s the only way to clean out a bad culture. Otherwise the culture perpetuates itself even as the personnel come and go.
In New York City even that may not be near enough, since the whole town is corrupt and its corruption radiates out for miles and miles like a volcano’s ash cloud.