20 ILCS 415/19c.1

(1) In any case involving any disclosure of information by an employee which the employee reasonably believes evidences-

(i) a violation of any law, rule, or regulation; or

(ii) mismanagement, a gross waste of funds, an abuse of authority, or a substantial and specific danger to public health or safety if the disclosure is not specifically prohibited by law, the identity of the employee may not be disclosed without the consent of the employee during any investigation of the information and any related matters.

(2) No disciplinary action shall be taken against any employee for the disclosure of any alleged prohibited activity under investigation or for any related activity. For the purposes of this Section, disciplinary action means any retaliatory action taken against an employee, including but not limited to reprimand, suspension, discharge, demotion or denial of promotion or transfer.