Mo. Rev. Stat. § 544.260

Persons arrested under any warrant for any offense shall, when no provision is otherwise made, be brought before the associate circuit judge who issued the warrant, or if he be absent or his office be vacant, or if he be not authorized to act within the county in which the offense was committed, then before the nearest associate circuit judge in such county; and the warrant by virtue of which the arrest was made, with a proper return endorsed thereon and signed by the officer or person making the arrest, shall be delivered to such associate circuit judge.