OIIG Investigation Process

Phone Number
Service Information

Investigation Process

Upon receipt of a complaint, a triage/screening process of each complaint is undertaken. In order to streamline the OIIG process and maximize the number of complaints that will be subject to review, if a complaint is not initially opened as a formal investigation it may also be reviewed as an “OIIG Inquiry.” This level of review involves a determination of corroborating evidence before opening a formal investigation. When the initial review reveals information warranting the opening of a formal investigation, the matter is upgraded to an “OIIG Investigation”.  Conversely, if additional information is developed to warrant the closing of the OIIG Inquiry, the matter will be closed.

All Cook County employees and vendors who appear for an interview at the request of the OIIG will be advised of their rights and duties with respect to the interview using standard OIIG forms. The specific warning form used for a particular interviewee will depend on whether the interviewee is an employee, vendor or elected official and whether the interview is compulsory or voluntary in nature. To your right under "Downloads" are the interview warning of rights and confidentiality forms used by the OIIG:

Our investigators may request the consent of the interviewee to make an audio recording of the interview. A copy of the Consent to Record Interview form can be found here

At the conclusion of a formal investigation, the assigned Investigator will make a recommendation based on a thorough assessment of all the information obtained.  Thereafter, the Independent Inspector General shall submit a confidential summary report to the Cook County Board President, the appropriate head of any department or bureau to whose office the investigation pertains, the Chief of the Bureau of Human Resources and to the Purchasing Agent in the case of a sustained finding regarding a contractor, subcontractor, applicant for a contract, or person seeking certification of eligibility for a contract, to any separate elected official when the investigation involves his/her office and to the Board of Ethics in the case of a sustained finding regarding any violation of the Cook County Ethics Ordinance.

Location Phone
Location Hours
Sunday: Closed
Monday: 9:00 am-5:00 pm
Tuesday: 9:00 am-5:00 pm
Wednesday: 9:00 am-5:00 pm
Thursday: 9:00 am-5:00 pm
Friday: 9:00 am-5:00 pm
Saturday: Closed