Ill. Admin. Code tit. 14 § 910.50
The hearing need not be conducted according to the technical rules of evidence. However, notwithstanding the foregoing, Section 12 of the Illinois Administrative Procedure Act (Ill. Rev. Stat. 1985, ch. 127, par. 1012) will apply. Any relevant evidence may be admitted in a hearing held pursuant hereto if it is of the type relied upon by reasonable, prudent persons in the conduct of their affairs, regardless of the existence of any common law or statutory rule which would render it inadmissable over objection in civil actions. The rules pertaining to privileged communications shall be recognized in these hearings to the same extent as they are recognized in civil actions. Irrelevant and unduly repetitious evidence shall be excluded.
Ill. Admin. Code tit. 14, § 910.50