40 ILCS 5/15-187
None of the benefits provided under this Article shall be paid to any person who is convicted of any felony relating to or arising out of or in connection with a person's service as an employee from which the benefit derives.
This Section shall not operate to impair any contract or vested right heretofore acquired under any law or laws continued in this Article, nor to preclude the right to a refund. The changes made to this Section by this amendatory Act of the 100th General Assembly shall not impair any contract or vested right acquired prior to the effective date of this amendatory Act of the 100th General Assembly. No refund paid to any person who is convicted of a felony relating to or arising out of or in connection with the person's service as an employee shall include employer contributions or interest or, in the case of the self-managed plan authorized under Section 15-158.2, any employer contributions or investment return on such employer contributions.
All persons entering service subsequent to July 9, 1955 shall be deemed to have consented to the provisions of this Section as a condition of coverage, and all participants entering service on or subsequent to the effective date of this amendatory Act of the 100th General Assembly shall be deemed to have consented to the provisions of this amendatory Act as a condition of participation.
40 ILCS 5/15-187