Missouri constitution
Article IV: executive department
Section 9

The governor shall, at the commencement of each session of the
general assembly, at the close of his term of office, and at such other times as he may
deem necessary, give to the general assembly information as to the state of the government,
and shall recommend to its consideration such measures as he shall deem necessary
and expedient. On extraordinary occasions he may convene the general assembly
by proclamation, wherein he shall state specifically each matter on which action is
deemed necessary.