Missouri constitution
Article III: legislative department
Section 45

When the number of representatives
to which the state is entitled in the House of the Congress of the United States under
the census of 1950 and each census thereafter is certified to the governor, the general
assembly shall by law divide the state into districts corresponding with the number of
representatives to which it is entitled, which districts shall be composed of contiguous
territory as compact and as nearly equal in population as may be.