Ill. Admin. Code tit. 35, § 166.260 – Testimony and Cross-Examination of Witnesses

a) All parties may cross-examine any other party's witness. The scope of cross-examination shall be defined by the scope of direct examination.
b) Employees of one party required by order of the Hearing Officer to attend a hearing may be examined as if under cross-examination.
c) 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.
d) Questions calling for an opinion of an expert witness need not be hypothetical in form.