Lawmakers voted 102-6 in favor of a measure that would allow a judge to impose a tougher punishment on anyone convicted of using social media to plan or incite a mob attack. The bill, which the Senate approved 52-0 last month, now goes to Gov. Pat Quinn.
The legislation was in direct response to incidents downtown Chicago and was supported by retailers there, though bill sponsor Rep. Christian Mitchell, D-Chicago, said it would make neighborhoods safer statewide.
Police say groups of young people used Facebook and Twitter, as well as text messaging, to organize and publicize a mob action along Michigan Avenue in March. They say several hundred people - mostly teenagers - ran up and down the upscale shopping area, yelling and bumping in to people. In a separate incident, police said a woman was attacked and her purse stolen after a group used social media to promote a flash mob on a downtown Chicago commuter rail line.
Business owners and lawmakers feared it would deter tourists and other visitors from coming to the area.
"These are new times where people are using electronic mechanisms to communicate to commit crimes in our neighborhoods," Rep. Ken Dunkin, D-Chicago. "When criminals change with the times we have to adjust ourselves accordingly."
Opponents of the bill worried innocent kids could get caught up in a flash mob and then be hit with a harsh penalty. They also said it would be difficult for authorities to prove.
Brooke Anderson, a spokeswoman for Gov. Quinn, said he would review the legislation.
"Public safety is the governor's top priority and we are always interested in good public policy that cracks down on crime," Anderson added.