Is blocking traffic legal?: Apparently, it is OK for illegal aliens

If a group of Christians were blocking traffic and harassing drivers, would they be arrested? From Fox News:

A federal judge blocked police in Arizona from enforcing a section of the state's 2010 immigration enforcement law that prohibited people from blocking traffic when they seek or offer day labor services on streets.
U.S. District Judge Susan Bolton ruled Wednesday that groups seeking to overturn the law will likely prevail in their claim that the day labor rules violate the First Amendment. . . .
Brewer's lawyers had opposed attempts to halt enforcement of the day labor restrictions. They argued the restrictions are meant to confront safety concerns, distractions to drivers, harassment to passers-by, trespassing and damage to property.
Brewer's lawyers have said day laborers congregate on roadsides in large groups, flagging down vehicles and often swarming those that stop. They also said day laborers in Phoenix and its suburbs of Chandler, Mesa and Fountain Hills leave behind water bottles, food wrappers and other trash. . . .