Missouri constitution
Article III: legislative department
Section 32

Every bill presented to the governor
and returned with his objections shall stand as reconsidered in the house to which
it is returned. If the governor returns any bill with his objections on or after the fifth
day before the last day upon which a session of the general assembly may consider
bills, the general assembly shall automatically reconvene on the first Wednesday following
the second Monday in September
for a period not to exceed ten calendar days
for the sole purpose of considering bills returned by the governor. The objections of
the governor shall be entered upon the journal and the house shall proceed to consider
the question pending, which shall be in this form: “Shall the bill pass, the objections
of the governor thereto notwithstanding? The vote upon this question shall be taken
by yeas and nays and if two-thirds of the elected members of the house vote in the
affirmative the presiding officer of that house shall certify that fact on the roll, attesting
the same by his signature, and send the bill with the objections of the governor to the
other house, in which like proceedings shall be had in relation thereto. The bill thus
certified shall be deposited in the office of the secretary of state as an authentic act and
shall become a law.