I had never seen such a sign before, and began to wonder what it really meant, and how such a thing could be enforced. Did it mean that none of the houses I walked past harbored absolutely no firearms? Or did it mean that no one was allowed to bring guns into the neighborhood? Was this some sort of state or local law? A neighborhood covenant? Just some sort of feel-good political statement? What? Unless gun ownership is banned by law, how can a "gun-free neighborhood" policy even be enforced?