I live in the toughest part of Minneapolis which is a fairly large city. It is bad enough so I have a carry permit and carry my pistol whenever I go out, even to mow the lawn. I've had to go for my weapon to avoid being robbed in the busy parking lot of a local store.
Watching drug deals going down is a normal thing to see, some bus shelters serve almost as drive through windows. The weekly police reports always reveal multiple felon in possession of firearms charges, guns taken away from juveniles, and people arrested for other crimes having weapons. Every week there are people shot, stabbed, and gravely injured.
I see police stops and searches all the time and sometimes stopped and filmed them. I keep a respectful distance, always make it apparent that I am taking pictures or video. I never try to interfere with or distract the officers while they are doing their job. I've never been asked to stop taking pictures, I've never been asked to step back or leave.
There are bloggers in this same neighborhood who have not had the same experience, some have had their phones/cameras seized as evidence, been threatened with arrest, and other things (or so they say on their blogs). But I have to say, these bloggers are loudmouths in their blogs and I have to believe that they probably push the envelope in real life as well.