40 ILCS 5/13-312
In those cases where injury or death for which any disability or other benefit because of death resulting from such injury is payable under this Article was caused under circumstances creating a legal liability for damages on the part of some person other than the employer, all of the rights and privileges, including the right to notice of suit brought against such other person and the right to commence or join in such suit, as given the employer, together with the conditions or obligations imposed under paragraph (b) of Section 5 of the Illinois Workers' Compensation Act or such similar provisions as might be set forth in the Workers' Compensation Act of any other state when such benefits are paid under the Workers' Compensation Act of such other state, are also given and granted to the retirement Board to the end that the fund may be paid or reimbursed for the amount of disability benefits paid or to be paid by the Fund to the injured employee or the employee's surviving spouse, children or personal representative out of any judgment, settlement, or payment for such injury or death obtained by such injured employee or the employee's spouse, children or personal representative from such other person.
40 ILCS 5/13-312