740 ILCS 110/12.1
A facility director or Department of Human Services employee who has reason to believe that a violation of criminal law or other serious incident has occurred within a mental health or developmental disability facility or while transporting a patient to or from a mental health or developmental disability facility shall report that violation or incident and the identity of individuals with personal knowledge of the facts related to the violation or incident to the appropriate law enforcement and investigating agencies.
In the course of any investigation conducted pursuant to a report made under this Section, any person with personal knowledge of the incident or the circumstances surrounding the incident shall disclose that information to the individuals conducting the investigation, except that information regarding a recipient of services shall be limited solely to identifying information as defined in Section 12.2 of this Act as well as the factual circumstances of the incident.
740 ILCS 110/12.1