Mo. Rev. Stat. § 541.160
Current with changes from the 2023 Legislative Session
Where the St. Francis River or the meanderings of said river border on or form the boundary line between any counties in the state of Arkansas and the state of Missouri, the state of Missouri shall have concurrent jurisdiction over any and all violations of the criminal laws of the state of Missouri, on and to the west meandering lines of the St. Francis River.
§ 541.160, RSMo
RSMo 1939 § 3778
For comparable Arkansas statute, see § 43.1403 Arkansas Statutes 1947