The Chicago Police Department has routinely spied on activist groups during the past six years, police records obtained by the Chicago Sun-Times show - including union members, anti-Olympics protesters, anarchists, the Occupy movement, NATO demonstrators and critics of the Chinese government. And it has continued to do so, according to the records ... which the police department fought to withhold. Under the department's rules, cops aren't allowed to purposely interfere with people exercising their free-speech rights. In recent years, though, department officials have repeatedly justified spying on protesters by saying they fear they might engage in disorder" and "civil disobedience." One investigation involving the surveillance of protest groups is still underway, 10 months after it was launched, the records show. The police won't say who is being investigated or discuss the methods being used. "There's something deeply disturbing about monitoring and documenting the exercise of First Amendment rights," says Molly Armour, an attorney who has represented protesters investigated by the police. In July, the Illinois attorney general's office issued an opinion saying "worksheets" - outlining the scope of these investigations - are public records under the state's Freedom of Information Act. The office ordered the police department to "promptly produce unredacted copies of the worksheets." It took nearly two months for the department to comply with the ruling.