Upon the appearance of the accused, he shall have reasonable time to answer the impeachment; and when the answer shall be filed, the managers may reply thereto; and when issue shall be joined on any such impeachment, the court or commission shall appoint a time for trial thereof.
§ 106.120, RSMo
RSMo 1939 § 12842, A.L. 1945 p. 1319 § 12846