SmugMug posted this link and I thought some of the 365Project community might find it useful as well. This is a printable, one-page document that can be easily tucked inside your camera bag.
@meredithwb Thank you for this information. I had a copy of this and misplaced it. I am finding that photographers are becoming more and more harassed. I now wear an I D on a lanyard from my photo club. I carry my photo club membership card with me. I want to take the time to make "business" cards for a third set of ID and one that I can hand to the person who questions me. I was questioned yesterday by a person who had seen me taking pictures several days ago. It would have been nice to have been able to hand him one of my cards.
http://www.aclu.org/free-speech/know-your-rights-photographers