Here are a couple of articles I ran across while searching for something else. "Gangster cops" is about a tragic, but inevitable result of the War on (some) Drugs, and the other article is about domestic enemy and authoriturd extraordinaire, Sheriff Joe Arpaio.
What I was originally looking for, but never found, was a flyer I had once run across online that warned of a new criminal gang, the "Blue Gang", and listed the typical behaviors and style of dress of cops and warned people to be alert and to regard this gang as extremely dangerous. If anyone can point me to it, I would be grateful and I will blog it here.