The Depth of Corruption in Illinois: A Comprehensive Report By University of Illinois at Chicago Department of Political Science

Professor Dick Simpson and his colleagues at University of Illinois-Chicago wrote(66 Page PDF) an outstanding report on Illinois corruption.Here's the beginning of the report:

Public corruption in Illinois has a long history dating from the first scandal involving Chicago aldermen and Cook County commissioners in the 1860s. At that time they participated in a crooked contract to paint city hall. Today, nearly a century and a half later, crooked contracts still cost the taxpayers millions of dollars a year and crooked politicians still go to jail.
As we continue our study of public corruption, we have discovered that our original findings underestimated the level of corruption in recent years. We now know that more than 1500 individuals have been convicted of myriad forms of public corruption since 1970. Based upon the testimony before the Illinois Reform Commission and our own research, we now believe that the cost of corruption, or “corruption tax,” for the Chicago and Illinois taxpayer is at least $500 million a year. This is based upon testimony before the commission that about 5% of state government contracts are given out to political cronies and campaign contributors and on our own tallies of the costs of the major scandals over the last four decades.
In our last report we provided a detailed analysis of the 30 aldermen and former aldermen convicted of public corruption since 1970. In this report we describe some of the major scandals of the last four decades, a timeline of more than 375 convicted individuals at all levels of government, and a further analysis of some of the costs of corruption which have caused us to revise our estimate of the corruption tax. The details of these scandals and their costs are included in the appendices of this report.
Our research on all aspects of corruption is continuing. But we provide this update to support the report of the Illinois Reform Commission and to contribute to the ongoing debate in the state legislature. Only comprehensive reforms can lessen the level of corruption in Chicago and Illinois, currently the capitals of corruption in the United States.

You'll want to read the whole report.Here's the another excellent report(PDF 49 Pages) Professor Simpson and his colleagues produced.Anyone concerned about the world President Obama came from should read these,then think about taking a shower.