40 ILCS 5/13-805
All annuities and benefits granted under this Article shall be exempt from attachment or garnishment process and shall not be seized, taken, subjected to, detained, or levied upon by virtue of any judgment, or any process or proceeding whatsoever issued out of or by any court, for the payment and satisfaction in whole or in part of any debt, damage, claim, demand, or judgment against any annuitant or other beneficiary hereunder.
No annuitant or other beneficiary shall have any right to transfer or assign an annuity or benefit or any part thereof, either by mortgage or otherwise except that an annuitant who elects to participate in any group hospital care plan or group medical or surgical plan shall have the right to authorize the Board to deduct the cost of such plan from the annuity check and to pay such deducted amount to the group insurance carrier; provided, that the Board, in its discretion, may pay to the spouse of any annuitant, or disability beneficiary, such amount from the annuity or disability benefit as any court of competent jurisdiction may order, or as the Board may consider necessary for the support of the spouse and children in the event of the disappearance or unexplained absence of the annuitant, or disability beneficiary, or of failure to support the spouse and children.
The Board may withhold from any future annuity or benefit payments such amounts as it may in its discretion require for the purpose of repayment into the Fund of any moneys paid to any annuitant, or disability beneficiary through misrepresentation, fraud or error. The Board, and the members thereof, and the Fund shall not be held liable for any amounts so withheld.
40 ILCS 5/13-805