Mo. Rev. Stat. § 21.050

If any person, whether a member or not, is guilty of any disorder in the presence of either house, or a committee of the whole of either house, or in joint meeting of both houses, while in session, the presiding officer of the house or joint meeting, or chairman of the committee of the whole, may order the person into custody; and the sergeant at arms or the doorkeeper shall immediately take the person into custody and detain him until the further order of the house, joint meeting or the house to which the committee of the whole belongs.