Idaho Admin. Code r. 37.01.01.600
Evidence should be taken by the agency to assist the parties' development of a record, not excluded to frustrate that development. The presiding officer is not bound by the Idaho Rules of Evidence. No informality in any proceeding or in the manner of taking testimony invalidates any resulting order. The presiding officer, with or without objection, may exclude evidence that is irrelevant, unduly repetitious, inadmissible on constitutional or statutory grounds, or on the basis of any evidentiary privilege provided by statute, rule or recognized in the courts of Idaho. All other evidence may be admitted if it is of a type commonly relied upon by prudent persons in the conduct of their affairs. The agency's experience, technical competence and specialized knowledge may be used in evaluation of evidence.
Idaho Admin. Code r. 37.01.01.600