20 ILCS 5010/20

(a) An ex officio member of the Commission vacates the person's position on the Commission if the person ceases to hold the position that qualifies the person for service on the Commission. (b) An ex officio member may designate a representative to serve on the Commission in the member's absence. A representative designated under this subsection must be an officer or employee of the State agency that employs the ex officio member or an individual with demonstrated expertise in the subject matter of the ex officio member's State agency.