How ever, my impression is that if you do photograph the police, they may be irritated and start harassing you, asking why you are taking photos of security personnel and such.
- It's probably legal though.
I have photographed the police in my own town, Oslo, when Obama came over to get his debated peace price, the whole city was full of heavily armed cops, quite a sight.
I've also photographed demonstrators and the police, but I suspect it is very important to stand in a place, where there is no doubt that you are not taking part in the demonstration in any way and be very visible while photographing. (I always make sure I use my white big-ass Canon 70-200 F2.8 L when I do that, as they simply assume that I am photographing for a paper or something )