The board for the trial of contests of elections for presidential electors shall consist of the chief justice of the supreme court, who must be president of the board, and two judges of the district court designated by the governor. If the chief justice is unable to attend at such trial, the next senior judge on the supreme court shall preside in place of the chief justice. The secretary of state must be the clerk of the board, or in the secretary of state’s absence or inability to act, the clerk of the supreme court must be the clerk. Each member of the board, before entering upon the discharge of the member’s duties, shall take an oath, before the secretary of state or some other officer qualified to administer oaths, that without fear, favor, affection, or hope of reward, the member will, to the best of the member’s knowledge and ability, administer justice according to law and the facts of the case.