The Fire Chief or his representative, when in his opinion further investigation is necessary, shall take or cause to be taken the testimony on oath, of all persons supposed to be cognizant of any facts or to have means of knowledge in relation to the matter as to which an examination is herein required to be made and shall cause the same to be reduced to writing. The Fire Chief shall have the power to summon witnesses before him to testify in relation to any matter which is, by the provisions of this article, a subject of inquiry and investigation, and may require the production of any book, paper or document pertinent thereto, and the Fire Chief is authorized to administer oaths to such witnesses.
(Code 1943, Art. 20-8)