Public Filming

Q: There was a film crew in my city filming a popular TV show in a restaurant and sidewalk in front of the restaurant. I took some pictures from the public sidewalk across the street.  None of my pictures were for anything but for my personal use--not commercial in any way.  One crew member said just not to use a flash.  Then 20 minutes later, another supposed crew person said I couldn't take any pictures because they had a permit and they threatened to call the police and got pretty belligerent.  I told the guy that I was in a public place and not encroaching on any filming efforts.  A police car showed up but took no action as we were leaving.  I read in California film regulations that no permit is required for non-commercial private-only family filming, but can a permitted film crew like the one I described stop me from taking pictures from a public place

A: The general rule is that photographing or filming what occurs on public property is legal.  A public sidewalk is a "public forum" for purposes of the First Amendment, and any restrictions on expression in such an area must be "narrowly drawn to achieve a compelling state interest."  Int’l Soc'y for Krishna Consciousness v. Lee, 505 U.S. 672, 678 (1992).  I am not aware of any authority for the proposition that if someone has a permit to use a certain public area, that entity could restrict your ability to take pictures in the public forum (absent a compelling state interest, which would generally not have to be something more compelling than helping an entity make a film).