Missouri constitution
Article III: legislative department
Section 15

Every senator or representative
elect, before entering upon the duties of his office, shall take and subscribe the
following oath or affirmation: “I do solemnly swear, or affirm, that I will support the
Constitution of the United States and of the state of Missouri, and faithfully perform
the duties of my office, and that I will not knowingly receive, directly or indirectly,
any money or other valuable thing for the performance or nonperformance of any act
or duty pertaining to my office, other than the compensation allowed by law.” The oath
shall be administered in the halls of the respective houses to the members thereof, by a
judge of the supreme court or a circuit court, or after the organization by the presiding
officer of either house, and shall be filed in the office of the secretary of state. Any
senator or representative refusing to take said oath or affirmation shall be deemed
to have vacated his office, and any member convicted of having violated his oath or
affirmation shall be deemed guilty of perjury, and be forever disqualified from holding
any office of trust or profit in this state.