Mo. Rev. Stat. § 545.850

Whenever any person charged with an offense shall be confined in jail two months before the regular term of the court in which he is to be tried, the jailer shall, without delay, inform the judge of such court thereof, who, if he shall be satisfied that a trial of such persons so confined can be had thereat, and the public good require, shall call a special term of court for the trial of such prisoner.