This article is behind a pay wall in the WSJ, but the Atlantic has a summary, which I've copied below. Floyd Abrams is a noted First Amendment Lawyer and he's concerned with the way some cities are dealing with a new phenomenon made possible by social media: flash mob violence. Recall that the recent revolutions in the Middle East and elsewhere have been made possible by social media. It's impact is not yet fully realized. Does government have the right to restrict its use since some might use it to organize criminal activity?
From the Atlantic Five:
Floyd Abrams on flash mobs and First Amendment rights Flash mobs--large groups that assemble by means of text message--sometimes act dangerously or lawlessly. "In doing so, they have raised difficult policy and legal issues, including questions relating to the role of the First Amendment," writes lawyer and author Floyd Abrams in The Wall Street Journal. Recently, mobs have beaten passersby and robbed stores. Official responses to the trend vary. In Cleveland, the city council passed a law banning "improper use of social media to violate ordinances on disorderly conduct, public intoxication and unlawful congregation by promoting illegal flash mob activity." During the British riots, David Cameron considered censoring social network sites. "But by focusing on the newer technological means of communication and not on the illegal conduct and its causes, they miss the point that it is not criminal to meet, let alone to plan to do so--but to engage in criminal conduct." The Cleveland mayor realized this and vetoed the proposed law. But the legality can become ambiguous. In San Francisco, the BART public transit system heard of a planned disruption to their service by groups organizing themselves by cell phone, so they disabled the underground fiber optic network. The plan worked, but the ACLU and others criticized the group for violating the liberties of all BART passengers. "As the proposed Cleveland statute illustrates, barring all people from engaging in constitutionally protected speech, even for a limited time in a limited space, raises troubling First Amendment issues," writes Abrams. "There will be more."