In the performance of official duties, the Board of Pardons or any member thereof shall have the power to issue subpoenas, to compel the attendance of witnesses and the production of books, papers, and other documents pertinent to the subject of an inquiry, and to administer oaths and take the testimony of persons under oath. Subpoenas so issued may be served by any sheriff, constable, police officer, parole officer, or peace officer in the same manner as similar process in the district court. Any person who knowingly testifies falsely, submits any false affidavit or deposition, fails to appear when subpoenaed, or fails or refuses to produce such material pursuant to the subpoena shall be subject to the same orders and penalties to which a person before the district court is subject. Any district court of this state, upon application by the board, may compel the attendance of such witnesses, the production of such material, and the giving of testimony before the board by an attachment for contempt or otherwise in the same manner as production of evidence may be compelled before such court. Every person shall attend as a witness when subpoenaed anywhere within the state and shall be entitled to the same fees, if requested, as a witness in the district court and mileage as provided in section 81-1176 for state employees. Fees, mileage, and actual expense, if any, necessarily incurred in securing the attendance of witnesses shall be paid by the board.