Ill. Admin. Code tit. 35, § 168.275 – Testimony and Cross-Examination of Witnesses

a) Written narrative testimony may be introduced by a party in a hearing only if provided to all other parties of record prior to the date of the hearing and only after the opposing parties have had an opportunity to object to all or portions of the written testimony and to obtain a ruling on said objections prior to its introduction. The person whose testimony is submitted shall be available at the hearing for cross-examination.
b) All parties may cross-examine any other party's witness. The scope of cross-examination shall be defined by the scope of direct examination.
c) Employees of one party required by order of the Hearing Officer to attend a hearing may be examined as if under cross-examination.
d) If the Hearing Officer determines that a witness is hostile or unwilling, the party calling the witness may examine the witness as if under cross-examination.
e) Questions calling for an opinion of an expert witness need not be hypothetical in form.