HJR 78 -- Adoption of Constitutional Amendments Sponsor: Smith (150) Upon voter approval, this constitutional amendment requires a three-fifths majority vote to amend the Missouri Constitution. Constitutional amendments adopted between November 1, 2001, and November 1, 2010, may be repealed in full by a simple majority vote if it implicates the repeal of a specific amendment and it doesn't substantively change the law.Copyright (c) Missouri House of Representatives