The Huffington Post, January 10, 2011 by Elise Foley
http://www.huffingtonpost.com/2011/01/10/heroic-giffords-intern-co_n_806999.html?ir=College
“If you are a witness for a crime, the officer would have a lawful reason to approach you, and if they had any reason to suspect you might be an alien, they could ask,” Aarti Kohli … told HuffPost. “The big question is what is reasonable suspicion.”