The board of auditors may issue subpoenas to obtain the attendance of the officers whose accounts they are required to audit or adjust, of their executors and administrators and of any person whom it may be necessary to examine as a witness and to compel their attendance, by attachment, the same as any court of common pleas may in cases pending before them and may also compel the production of all books, vouchers and papers relative to township accounts. The subpoena and attachment shall be issued by a district justice. The board of auditors may administer oaths and affirmations to all persons brought or appearing before them, whether accountants, witnesses or otherwise. All persons swearing or affirming falsely upon examination are guilty of perjury.