The City of Chicago opened its official internal investigative offices with the 1956 establishment of the Department of Investigation. The office was re-named as the Office of Professional Review in the late 1970’s after the Chicago Sun-Times and Better Government Association performed an undercover investigation (the Mirage Scandal) and found numerous inspectors and other City employees accepting bribes from the owners of a tavern. On January 1, 1981, that office was changed to the Office of Municipal Investigations.

Among the common features of these offices were that the commissioner or director of each of these offices served at the pleasure of the Mayor, and none had subpoena power.

To correct these limitations on investigative independence and effectiveness, the 1989 ordinance which established OIG contains various provisions to ensure the Office’s independence. The ordinance establishing OIG called for an Inspector General to be appointed by the Mayor and subject to the approval of the City Council. The Inspector General is appointed to a four-year term and can only be removed “for cause.”

Additionally, the ordinance creating OIG provided for investigative powers previously denied to the City’s internal investigative agencies. The Inspector General has the power to issue subpoenas to compel the attendance of witnesses for purposes of examination, as well as the production of documents and other items for inspection and/or duplication.

Lastly, the ordinance establishing OIG deems that it shall be the duty of every officer, employee, department, agency, contractor, subcontractor and licensee of the City and every applicant for certification of eligibility for a City contract or program, to cooperate with the Inspector General in any investigation or hearing undertaken. Likewise, every City contract and every bid, proposal, application, or solicitation for a City contract, and every application for certification of eligibility for a City contract or program must contain a statement that the person understands and will abide by all provisions of the ordinance establishing OIG.