40 ILCS 5/15-170
To maintain a permanent record of all board proceedings which record shall be available for examination by any participant, annuitant or officer of the State of Illinois; to maintain a separate record for each individual participant and annuitant; to maintain adequate accounting records which shall at all times reflect the financial condition of the system, and such additional data as shall be necessary for required calculations, valuations and operation of the system; to have any of the foregoing records photographed, microfilmed or otherwise reproduced, which photographs, microfilms or reproductions shall be deemed original records for all purposes, including introduction in evidence before all courts and administrative agencies.
40 ILCS 5/15-170