This book is really good, and I kind of wish it had a different cover.
This book primes you to think that it is about the gestalt of policing, that it is a rhetorical argument against the police state.
And in a lot of ways, it builds to that! But the methodology of the book is so sound and sober it's easy to forget. The book's argument is simple: the police do too much and they do all of it poorly, here are some examples. In true catalog fashion, the examples get weaker as the book progresses, but the opening choice — police in schools — is so representative of the book's overall effectiveness.
I don't have a lot of interesting things to say about this book. I think it's effective and well-written. It has useful and pragmatic things to say. It changed my view from an abstract "police are bad but that's life" to a concrete one. You should read this book.