Hey, don't knock us New Yorkers.

Seriously, it looks a lot like the guy provoked that reaction, not only by using a non-digital camera, but then the policeman becomes a bit...weird in his argumentation as well. New York must be a bad place for tourorists who just want to take pictures of the nice subway tracks.
I saw a couple of French tourists actually photographing the subway maps. What epic noobs.

New York's police force is the size of a small army (35000+). It's bound to have a few unsavory characters. I think we have a couple of trials going on with police officers who shot and killed innocent men. It's usually pretty decent, though.