Rule 4-104. Evidence.
   (a)   Generally. The Chair may admit evidence which possesses probative value commonly accepted by reasonable and prudent persons in the conduct of their affairs. The Chair shall give effect to the rules of privilege recognized by law. The Chair may exclude incompetent, irrelevant, immaterial, and unduly repetitious evidence.
   (b)   Documentary evidence. Documentary evidence may be received in the form of copies or excerpts, or by incorporation by reference. Exhibits and plats admitted into evidence may not be mounted and shall be folded to a maximum size of nine inches by 14 inches. An exact duplicate of the exhibit may be mounted and used for presentation.
   (c)   Cross-examination. The parties shall have the opportunity to cross-examine witnesses. The Chair shall permit a representative or representatives of persons in opposition the opportunity to conduct cross-examination.
   (d)   Authority to testify. The Chair may question witnesses testifying as representatives of associations as to their authorization to testify on behalf of the association, and may permit cross-examination as to the authorization by those representing parties to the appeal.
   (e)   Expert witnesses. The Chairman may qualify expert witnesses on the basis that their testimony, in the form of an opinion or otherwise, will assist the Board in understanding evidence or determining a fact at issue. In making the qualification, the Chairman shall consider (1) whether the witness is qualified as an expert by knowledge, skill, experience, training or education; (2) the appropriateness of the testimony for the particular case; and (3) whether sufficient facts exist to support the testimony.
(Bill No. 53-86; Bill No. 22-90; Bill No. 99-93; Bill No. 5-10)