See Full Constitution
Article IV
Section 25. Stationery and printing
The legislature shall provide by law that all stationery required for the use of the state, and all printing authorized and required by them to be done for their use, or for the state, shall be let by contract to the lowest bidder, but the legislature may establish a maximum price; no member of the legislature or other state officer shall be interested, either directly or indirectly, in any such contract.