Mo. Rev. Stat. § 107.140: Annual examination of official bonds.

As soon as practicable after the taking effect of this law, and at least once in each year thereafter, the officers and courts required by law to examine and approve any such bonds shall examine as to their sufficiency and as to the solvency of the sureties therein, and shall briefly note thereon, or on the record thereof, the result of such examination; and if any such bond be for any reason deemed insufficient, the principal therein shall be required by a notice in writing to furnish a new and sufficient bond within thirty days; and if such bond be not so furnished and approved, the office shall at the expiration of said thirty days become vacant, and the vacancy shall be filled as provided by law.