As long as the public can access the location, you can take pictures. Media coverage and usage is a little different as the message shouldn't, ethically that is, be made out of context, but you should still be able to take pictures.
Police are public figures and are in public view. I've had police officers threatening to "dispose or brake" my camera, but I always "inform" them that I had as much right to keep on taking pictures, unless the area is blocked off and under investigation. Some tried to take forcefully (verbally, not physically) confiscate my camera/memory card, but a quick call to a photo editor or lawyer gets them off my back and most of the time, it's regular patrol cops who don't know the proper procedures of handling the media.
My friend was actually with me when I got pulled over and he parked and got out to accompany me. The "junior cop" yelled at my friend to move along and that he had no right to be here, even though he was 15 feet away on a public sidewalk. My friend starts to take pictures and it pissed of the "junior cop". I say junior cop because he looked he was 15 and acted like one too. There was another cop, the one in the picture, who was much more level headed and tried to cool him down.
They told my friend to leave the area as it was under an investigation... I know the law and a traffic violation isn't an investigation. Maybe he used the wrong phrase of words, but he was in the wrong to "force a pedestrian off public sidewalks and command him to get back into his car". I could have easily been an asshole and made my friend stay and claim him to be my legal council, but that would probably make situations much more worse.
After my friend left, I continued on being me and took pictures of anything and everything. A tree, a bug, the building, the bike, a rock... you get the picture. After that, they were much more less jumpy.
With that being said, My friend and I are looking into legal actions against the city of Raleigh, but we'll probably not do a thing. We'll just mention the situation to the DA as a complaint and request that the two officers be "properly trained in media relations". The last thing you want to do is to piss off the media, especially with my past track record. I mean seriously... why fuck with a guy who has a handicapped sticker on the side of his bike and carries a big ass camera everywhere like a fuckin samari sword??? That's just more trouble that its worth and what I strive for.