SEC. 5-7. WITNESSES.
   The hearing officer may determine whether oral evidence shall be taken under oath or affirmation. The hearing officer shall receive oral evidence given in either a formal or informal style. The hearing officer shall permit the parties to call and examine witnesses, to introduce exhibits, to cross-examine witnesses on any matter relevant to the issues even though such matter was not covered on direct examination, and to impeach any witness regardless of which party first called the witness to testify.
(`64 Code, Sec. 5-2.5) (Ord. No. 2239, 2375, 2639)