S.D. Const. art. XXVI, § 19

Tenure of elected officers. The tenure of all officers, whose election is provided for in this schedule, on the first day of October, A. D. 1889, shall be as follows: The Governor, lieutenant governor, secretary of state, auditor, treasurer, attorney general, superintendent of public instruction, commissioner of school and public lands, judges of county courts, shall hold their respective offices until the first Tuesday, after the first Monday, in January, A. D. 1891, at twelve o'clock m., and until their successors are elected and qualified. The judges of the Supreme Court and circuit courts shall hold their offices until the first Tuesday, after the first Monday, in January, A. D. 1894, at twelve o'clock m., and until their successors are elected and qualified; subject to the provisions of § 26 of article V of the Constitution. The terms of office of the members of the Legislature, elected at the first election held under the provisions of this Constitution, shall expire on the first Tuesday, after the first Monday, in January, 1891.