In Chicago on May Day about 20,000 people gathered in Union Park and marched to Daley Plaza. There was a lively anarchist bloc within the march that played music using horns, drums and other instruments. The protest was for immigrant solidarity, worker solidarity and against war. The march started out peacefully. After the march arrived in Daley Plaza a line of police on horseback rammed into a group of protesters without warning. The horses shoved and kicked protesters. At least one person was arrested. The local corporate media always says the protests in Chicago are peaceful. Those of us who frequently attend these protests know this is a lie. Chicago police typically attack and arrest peaceful demonstrators several times a year. 50-100 cops in riot gear are a common sight at Chicago protests. The police in Chicago have a long history of attacking protesters without warning or provocation. The Chicago police have also been known to verbally insult protesters.
The political climate in Chicago is very repressive. Chicago has more police cameras than any other US city. Chicago has a fascist mayor, Richard Daley, who has been in office for 20 years, who rigs elections, who actively supports police brutality, torture, war and who crushes dissent with an iron fist. The following is a list of violent police attacks on protesters in Chicago that occurred recently. A complete description of police brutality at Chicago protests going back 150 years or so would fill a book.

Chicago police brutally attack a protester at the anti-war demonstration on March 14, 2009. The protester was hospitalized after the attack and put on trial.
www.counterpunch.org/allen04302010.html

Chicago police attack the Bash Back march with batons on May 30, 2009. Several people were injured and arrested after getting hit with batons.
twincities.indymedia.org/2009/jun/unprovoked-police-riot-bash-back-convergence-may-30

Chicago police attempt to physically blockade a march against police brutality on June 26, 2009.
www.chicagobreakingnews.com/2009/06/protesters-greet-1968-police-reunion.html

Chicago police attack and arrest several people at the anti-Olympics protest on September 29, 2009.
www.chicagobreakingnews.com/2009/09/olympics-banner-vandalized-6-arrested.html