The ebook version of this is free on the Verso (the publisher) website. Go grab it! It's real good. Clear, concise, engaging and really well structured, it lays out with great care how at it's core (and on the surface too, really) policing isn't that different from it's original form as a racist, classist organization at the service of the privileged whose operations, far from reducing crime, mostly help to exacerbate and validate injustices and mishandle society's needs, a nature it's structurally/fundamentally unable to escape from. Dismantle it entirely.