The mass arrests of Occupy Chicago demonstrators that city leaders held up as a model for how to respect protesters' rights has been ruled unconstitutional and tossed out of court by a Cook County judge.



In a 37-page ruling issued today, Associate Judge Thomas Donnelly ruled the October 2011 arrests were unconstitutional because the city routinely chooses not to enforce the curfew for events the city supports, such as the 2008 Election Night rally for President Barack Obama. The judge noted that no arrests were made at that event, even though it went well past curfew.



With the ruling, the arrests of 92 Occupy protesters on charges related to violating the curfew were thrown out.



In the months leading up to this spring's NATO conference in Chicago, Mayor Rahm Emanuel's administration had pointed to the handling of the arrests by his police superintendent, Garry McCarthy, as an ideal way to keep order while respecting protesters' rights. During the 2011 demonstrations, on two consecutive Saturdays in October, police issued a clear order for protesters to leave Grant Park, and then gave people ample time to disperse.



The handling of the demonstrations stood in sharp contrast to a 2003 Iraq War demonstration in which more than 500 people were arrested after police refused to allow them to leave the intersection of Michigan and Chicago avenues.



But Donnelly ruled the city had no constitutional right to order people out of the park last October.



"We're incredibly pleased by Judge Donnelly's ruling. This is a significant First Amendment ruling for the Occupy protesters, and all Chicagoans," said lawyer Thomas A. Durkin, who represented 12 University of Chicago students who were among the 92 arrested.



City lawyers are disappointed and plan to appeal, said Law Department spokesman Roderick Drew.



More than 300 people were arrested in the Grant Park demonstrations early in the morning on Oct. 16 and Oct. 23, 2011, for violating the curfew, which bans people from being in Chicago parks between 11 p.m. and 6 a.m.



Durkin and lawyers from the National Lawyers Guild, which also represented defendants, said it was unclear whether the ruling would affect the cases of the more than 200 arrestees who had earlier taken court-supervision offers from the city to avoid having a conviction on their records.



dheinzmann@tribune.com