The Missouri Supreme Court declined Monday to hear an appeal in a lawsuit opposing a proposed constitutional amendment to eliminate the state income tax by expanding sales and use taxes to make up for lost revenue.
That means Missouri voters will decide in the Aug. 4 primary election whether to give lawmakers the ability to expand those taxes.
In May, Gov. Mike Kehoe announced the measure, titled Amendment 5, would appear on the August ballot instead of the November one.
A lawsuit filed against the amendment argued that it improperly amended Missouri's constitution. It also called the ballot's summary statement misleading.
Cole County Circuit Judge Christopher Limbaugh rejected those arguments last week. The plaintiffs appealed the ruling.
On Friday, the Missouri Western District Court of Appeals also ruled that the amendment will remain on the August ballot.
However, the court reversed Limbaugh's ruling on the summary, saying it must be changed because it did not provide enough information.
The new summary, put forth by the Court of Appeals, will now say:
Shall the Missouri Constitution be amended to:
• Require legislative phase-out of the individual state income tax based on revenue growth, and authorize the expansion of sales and use taxes;
• Curtail constitutional limits on taxing goods and services; and
• Require local tax rate cuts without reducing school funding if local sales tax revenue increases?
Despite succeeding on the ballot summary portion of the lawsuit, the plaintiffs in the case further appealed the decision to the Missouri Supreme Court.
Because the Missouri Supreme Court decided not to hear the case, the Court of Appeals ruling stands. That means the amendment will be listed on the August ballot.
The courts had a tight deadline to rule on this case. State law requires all changes to the primary ballot to be finalized on June 9.
In addition to Amendment 5, three other proposed constitutional amendments will appear on the same ballot, including one that aims to make it harder to amend Missouri's constitution through the initiative petition process.
Missouri voters have approved constitutional amendments brought through initiative petition in prior elections, including overturning Missouri's near-total abortion ban and legalizing recreational marijuana.
Copyright 2026 St. Louis Public Radio