820 ILCS 40/9
An employer shall not gather or keep a record of an employee's associations, political activities, publications, communications or nonemployment activities, unless the employee submits the information in writing or authorizes the employer in writing to keep or gather the information. This prohibition shall not apply to (i) activities or associations with individuals or groups involved in the physical, sexual, or other exploitation of a minor or (ii) the activities that occur on the employer's premises or during the employee's working hours with that employer which interfere with the performance of the employee's duties or the duties of other employees or activities, regardless of when and where occurring, which constitute criminal conduct or may reasonably be expected to harm the employer's property, operations or business, or could by the employee's action cause the employer financial liability. A record which is kept by the employer as permitted under this Section shall be part of the personnel record.
820 ILCS 40/9