Columbia Mayor ordinance (Charter § 10)

The council member elected at large shall be the mayor, but shall have no regular administrative duties. The council member-at-large shall preside at all meetings of the council, and shall be recognized as head of the city government for all legal and ceremonial purposes and by the governor for purposes of military law. The council member-at-large shall have the same right to vote as any other member of the council, but shall have no veto power. The council shall also select from among the council members a mayor "pro tempore," who shall act as mayor during the absence or disability of the mayor. If a vacancy should occur, the mayor "pro tempore" shall become mayor for the completion of the unexpired term unless that term is for a period exceeding one year.