From TalkLeft, I found this article from the New York Times, called "Reporting While Black" which describes an African American reporter's experience trying to interview suspected gang members in Salisbury, North Carolina (population 30,000).
One part of the article that caught my attention was this scene when the 37-year old reporter approaches some young black men on the street, whom he suspects of selling drugs, to interview them:
“Man, you a cop,” said another. “Hey, this guy’s a cop!”
“You’ve got me wrong,” I said trying to sound casual as the men looked at me warily. I started to pull my press identification out of my wallet. “I’m a reporter. I’m just trying to talk to you about your neighborhood.”
In the distance I heard neighborhood lookouts calling: “Five-O! Five-O!” — a universal code in American ghettos for the approaching police. I thought they were talking about me, but thought again as three police cars skidded to a stop in front of us.
A tall white police officer got out of his car and ordered me toward him. Two other police officers, a white woman and a black man, stood outside of their cars nearby. I complied. Without so much as a question, the officer shoved my face down on the sheet metal and cuffed me so tightly that my fingertips tingled.
“They’re on too tight!” I protested.
“They’re not meant for comfort,” he replied...
After a quick check for outstanding warrants, the handcuffs were unlocked and my wallet returned without apology or explanation beyond their implication that my approaching young black men on a public sidewalk was somehow flouting the law.
“This is a dangerous area,” the officer told me. “You can’t just stand out here. We have ordinances.”
“This is America,” I said angrily, in that moment supremely unconcerned about whether this was standard police procedure or a useful law enforcement tool..
It's an interesting article, and I don't cite it as an example of aggressive police tactics but rather to gauge your thoughts on the author's point that "the problem is that when the police focus on gangs rather than the crimes they commit, they are apt to sweep up innocent bystanders, who may dress like a gang member, talk like a gang member and even live in a gang neighborhood, but are not gang members."
After all, we are talking about what is probably suspicious behavior: a well-dressed man approaching people visibly selling drugs in a high-crime area after dark. However, in this case, and in a lot of others no doubt, the individual caught up was, in his words:
At 37 years old, I’m beyond the street-tough years. I suppose I could be taken for an “O.G.,” or “original gangster,” except that I don’t roll like that — I drive a Volvo station wagon and have two young homeys enrolled in youth soccer leagues.