They were holding a martial arts demonstration for kids at a library (in New Jersey) and I was covering the event with photos for my local paper. But as soon as I took out my camera, a librarian started huffing at me that I needed releases from the parents to take pictures of their children. She was nice enough to actually find some releases and have the parents sign them for me so I didn't have any real trouble, but I missed the first critical minutes of the demonstration because of this. I'm curious about the legal grounds she had.
A library is owned by the town or state, so it's public property, and isn't it always legal to photograph anyone on public property, regardless of their age, as long as there isn't a "national security situation" and nobody objects to being photographed, and don't the press have expanded rights?
The reason she gave me was "kidnappers and pedophiles, you never know these days, so it's our policy," without being so clear if it was the township or the library's policy.

