Main Office
69 W. Washington, Suite 1160
Chicago, IL 60602
Phone Number
(312) 603-0350
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Welcome to the Office of the Independent Inspector General (OIIG). Please be aware that due to the circumstances surrounding COVID-19, the OIIG will not be accepting in-person meetings with the public at this time. OIIG Investigators are available by telephone and through e-mail. Please contact (312) 603-0350 if you would like to speak with an OIIG Investigator. Thank you for your cooperation and understanding. 

Mission Statement

The mission of the OIIG is to detect, deter and prevent corruption, fraud, waste, mismanagement, unlawful political discrimination and misconduct in the operation of Cook County government with integrity, independence, professionalism and respect for both the rule of law and the people we serve. The OIIG conducts investigations and issues findings and recommendations to Cook County government officials. The OIIG also investigates potential criminal violations involving the conduct of Cook County employees acting in their official capacities and refers such matters for prosecution. Because the OIIG is a fact-finding agency, it cannot dictate a legal outcome.

The OIIG also serves as a liaison between the County and outside law enforcement authorities and prosecutorial agencies when cases are referred.

The OIIG's jurisdiction includes employees, elected and appointed officials in the performance of their official duties, as well as contractors and subcontractors doing or seeking to do business with Cook County government.