On complaint by or on behalf of any convict to any county or county district officer, that such convict had been improperly treated in any respect, it shall be the duty of such officer at once to investigate the complaint, and if it is believed to be well founded, to report the facts to the president of the board of supervisors, or to the board in session. Upon such report the board shall cite the person complained of to appear before it, and such action shall be taken by the board as shall be proper.