The board of county commissioners is hereby vested with full power to inquire into and investigate the accounts, disbursements, bills and expenses of any county, district, or township officer, and to that end may subpoena witnesses and in case any witness fails or refuses to obey any lawful order of the board of county commissioners he shall be deemed guilty of a misdemeanor, but in no case shall the board of county commissioners allow any compensation, fee, salary, bills or expenses to any officer or person except when expressly allowed by law.
R.L. 1910, § 1601.