40 ILCS 5/1-122
Notwithstanding any provision in this Code to the contrary, if a person serves as a part-time employee in any of the following positions: Legislative Inspector General, Special Legislative Inspector General, employee of the Office of the Legislative Inspector General, Executive Director of the Legislative Ethics Commission, or staff of the Legislative Ethics Commission, then (A) no retirement annuity or other benefit of that person under this Code is subject to forfeiture, diminishment, suspension, or other impairment solely by virtue of that service and (B) that person does not participate in any pension fund or retirement system under this Code with respect to that service, unless that person (i) is qualified to so participate and (ii) affirmatively elects to so participate. This Section applies without regard to whether the person is in active service under the applicable Article of this Code on or after the effective date of this amendatory Act of the 93rd General Assembly. In this Section, a "part-time employee" is a person who is not required to work at least 35 hours per week.
40 ILCS 5/1-122