Mo. Const. art. III, § 38(a)

The general assembly shall have no power to grant public money or property, or lend or authorize the lending of public credit, to any private person, association or corporation, excepting aid in public calamity, and general laws providing for pensions for the blind, for old age assistance, for aid to dependent or crippled children or the blind, for direct relief, for adjusted compensation, bonus or rehabilitation for discharged members of the armed services of the United States who were bona fide residents of this state during their service, and for the rehabilitation of other persons. Money or property may also be received from the United States and be redistributed together with public money of this state for any public purpose designated by the United States. [Effective - 27 Feb 1945 , see footnote]