What's your alternative? No police? This idea that there can, anywhere, be an organization that makes zero mistakes is a childish fantasy. Some things, when they screw up do a LOT more harm than others. Police among them. It sucks. That's the real world. But seriously... What's your all-knowing alternative? How does your no-police world work? Is there no law at all? Is everybody deputized to enforce the law? What is it like to live in your world?
What's your alternative? No police?
Now, knock down your straw man.