This flyer, (pdf perfect for keeping in your camera bag or in your wallet) describes what rights one has when harassed by either rent-a-cops (like in this disturbing story in San Francisco), or members of local constabulary. Bottom line, don't let your rights as a U.S. citizen be taken by some faceless uniformed officer.
Bert P. Krages II — Attorney at Law: The Photographer's Right - A Downloadable Flyer:
The right to take photographs is now under assault more than ever. People are being stopped, harassed, and even intimidated into handing over their personal property simply because they were taking photographs of subjects that made other people uncomfortable. Recent examples have included photographing industrial plants, bridges, and bus stations. For the most part, attempts to restrict photography are based on misguided fears about the supposed dangers that unrestricted photography presents to society.
Ironically, unrestricted photography by private citizens has played an integral role in protecting the freedom, security, and well being of all Americans. Photography in the United States has contributed to improvements in civil rights, curbed abusive child labor practices, and provided information important to investigating crimes. These images have not always been pretty and often have offended the sensibilities of governmental and commercial interests who had vested interests in a status quo that was adverse to the majority in our country.
Photography has not contributed to a decline in public safety or economic vitality in the United States. When people think back to the acts of terrorism that have occurred over the last forty years, none have depended on or even involved photography. Restrictions on photography would have not prevented any of these acts. Similarly, some corporations have a history of abusing the rights of photographers under the guise of protecting their trade secrets. These claims are almost always meritless because entities are required to keep trade secrets from public view if they want to protect them. Trade secret laws do not give anyone the right to restrain photographers from taking photographs from public places.