Chicago is the county seat of Cook County. The government of the City of Chicago is divided into executive and legislative branches. The Mayor of Chicago is the chief executive, elected by general election for a term of four years, with no term limits. The mayor appoints commissioners and other officials who oversee the various departments. In addition to the mayor, Chicago's two other citywide elected officials are the clerk and the treasurer.
The City Council is the legislative branch and is made up of 50 aldermen, one elected from each ward in the city. The council enacts local ordinances and approves the city budget. Government priorities and activities are established in a budget ordinance usually adopted each November. The council takes official action through the passage of ordinances and resolutions.
During much of the last half of the 19th century, Chicago's politics were dominated by a growing Democratic Party organization dominated by ethnic ward-heelers. During the 1880s and 1890s, Chicago had a powerful radical tradition with large and highly organized socialist, anarchist and labor organizations. For much of the 20th century, Chicago has been among the largest and most reliable Democratic strongholds in the United States, with Chicago's Democratic vote the state of Illinois has been "solid blue" in presidential elections since 1992. The citizens of Chicago have not elected a Republican mayor since 1927, when William Thompson was voted into office. The strength of the party in the city is partly a consequence of Illinois state politics, where the Republicans have come to represent the rural and farm concerns while the Democrats support urban issues such as Chicago's public school funding. Chicago contains close to 25% of the state's population, and as such, eight of Illinois' 19 U.S. Representatives have part of Chicago in their districts.
Former Chicago Mayor Richard J. Daley's mastery of machine politics preserved the Chicago Democratic Machine long after the demise of similar machines in other large U.S. cities. During much of that time, the city administration found opposition mainly from a liberal "independent" faction of the Democratic Party. The independents finally gained control of city government in 1983 with the election of Harold Washington. From 1989 until May 16, 2011, Chicago has been under the leadership of Richard M. Daley, the son of Richard J. Daley. Because of the dominance of the Democratic Party in Chicago, the Democratic primary vote held in the spring is generally more significant than the general elections in November. On May 16, 2011, Rahm Emanuel was sworn in as the 55th mayor of Chicago, ending a 22-year era led by Richard M. Daley.
Chicago has four main sections: Downtown (which contains the Loop), the North Side, the South Side, and the West Side. The three sides of the city are represented on the Flag of Chicago by three horizontal white strips. These sections can further be informally subdivided or grouped, for example as shown on the map (right). Further sectional references are the Northwest side and the Southwest side. In the late 1920s, sociologists at the University of Chicago subdivided the city into 77 distinct community areas, which can further be subdivided into over 200 neighborhoods.
The central commercial area often is portrayed, as in the map at right, to include parts of Near North Side and Near South Side, as well as the Loop. The North Side is the most densely populated residential section of the city and many high-rises are located on this side of the city along the lakefront. The South Side is the largest section of the city, encompassing roughly 60% of the city's land area. The South Side contains the University of Chicago and most of the facilities of the Port of Chicago.
Chicago's streets were laid out in a street grid that grew from the city's original townsite plat. Streets following the Public Land Survey System section lines later became arterial streets in outlying sections. As new additions to the city were platted, city ordinance required them to be laid out with eight streets to the mile in one direction and 16 in the other direction. The grid's regularity would provide an efficient means to develop new real estate property. A scattering of diagonal streets, many of them originally Indian trails, also cross the city. Many additional diagonal streets were recommended in the Plan of Chicago, but only the extension of Ogden Avenue was ever constructed.
Murders in the city peaked first in 1974, with 970 murders when the city's population was over three million people (resulting in a murder rate of around 29 per 100,000), and again in 1992 with 943 murders, resulting in a murder rate of 34 per 100,000. Chicago, along with other major US cities, experienced a significant reduction in violent crime rates through the 1990s, eventually recording 448 homicides in 2004, the lowest total since 1965 (15.65 per 100,000.) Chicago's homicide tally remained steady throughout 2005, 2006, and 2007 with 449, 452, and 435 respectively.
In 2008, murders rebounded to 510, 2nd highest in the country, breaking 500 for the first time since 2003.For 2009 the murder count was down about 10% for the year, to 458.
2010 saw Chicago's murder rate at its lowest levels since 1965. Overall, 435 homicides were recorded for the year, a 5% decrease from 2009.