Those demonstrating Monday accused Mayor Rahm Emanuel's administration of trying to repress their movement. Chicago police arrested more than 100 people this past weekend for defying orders to leave Grant Park after closing time.
The protesters made their way inside city hall near the mayor's office Monday. They say their First Amendment rights were violated.
However, Mayor Emanuel defended the Chicago Police Department Monday and the arrests, which were made early Sunday.
The group National Nurses United says some of 130 people arrested and taken into police custody were registered nurses working at a medical stand set up to treat protesters, some, they said, who needed medical attention.
Those arrested refused to leave after the park closed at 11 p.m. Saturday.
The protesters say police departments in other cities are allowing "Occupy" groups to camp out in park areas overnight.
"They continue to have the right to express themselves, and they always will because we have one of the most important things in our country, which is a people's First Amendment. And, we have to apply the law as it is stated, which says there's a curfew at Grant Park. Curfew starts at 11. Everybody was told it starts at 11. My understanding is the arrests did not occur until after 12:30," Emanuel said Monday.
"We were some of the last protesters arrested because they didn't want there to be media present when we were released. I ate six pieces of white bread and one piece of bologna in that 22-hour period. We were denied our legal right to call an attorney. We were not allowed to make a single phone call the entire time that we were held there. They confiscated our mattresses-- despite the fact that other prisoners had access mattresses. We were laying on cold concrete slab, uncomfortable, freezing, bright lights over head, unable to sleep. It was really deplorable, and I don't think anybody should be treated like that," said Jan Rodolfo of National Nurses United.
Demonstrators contend the law in Chicago is more aggressive than in other cities.
CPD Supt. Garry McCarthy would not talk about the arrests as he walked into a private event Sunday evening.
Mayor Emanuel says his administration will protect the First Amendment rights and will also uphold the law. If the park closes at 11, he will enforce the law, and the police will enforce that law.
