San Francisco Chronicle, Nov. 4, 2008 by Chip Johnson
http://www.sfgate.com/cgi-bin/article.cgi?f=/c/a/2008/11/04/BAF013TFRH.DTL
“Cities are well within their legal rights to regulate speech—and in this case, the right to assembly—when it can show a compelling government interest, such as curbing retaliatory violence,” said Dan Farber, constitutional law professor at UC Berkeley.