Missouri Republicans have sought for years to make it harder to amend the state's constitution.
On Tuesday, Missourians will decide whether to back that quest.
GOP legislators have been frustrated by the state's voters ratifying left-of-center ballot items over the years. Amendment 4 would require any proposed constitutional amendments put to voters through the initiative petition process to win a statewide majority and majorities in all eight congressional districts.
Backers of the plan say that the current statewide majority standard is too easy and that it doesn't require buy-in from Missouri's rural areas.
"I think it gets back to how the conversation starts," said Missouri Farm Bureau President Garrett Hawkins. "And the conversation never starts on a widespread basis across the state. The conversation is initiated in Kansas City and St. Louis to start with."
Amendment 4's detractors, including some Republicans, say the plan is an extreme overreaction and would make it impossible for Missourians to kick-start any changes to their constitution. Opponents also assailed the fact that constitutional amendments proposed by the legislature would only need a simple majority.
"I really think it comes down to this mentality that they have now, or that they seem to have, where they really think that they are our rulers," said University City resident Lisa Hummel, an Amendment 4 foe. "They think that they know better than we do as citizens."
A decade-plus in the making
Republicans currently control every statewide office and have a supermajority in the General Assembly thanks to the party's dominance in rural counties and fast-growing suburbs like Jefferson and Lincoln counties.
But during the decade of GOP electoral victories, Missourians also backed constitutional amendments expanding Medicaid, legalizing marijuana, approving sports betting and repealing the state's restrictive abortion ban. They've also passed statutory initiatives raising the minimum wage.
That prompted GOP lawmakers and statewide officials to advocate for raising the threshold to pass a constitutional amendment. Other proposals included requiring 60% or 57% of a statewide vote to ratify an amendment or obtaining a successful statewide vote and majorities in five of eight congressional districts.
During a special session in 2025, lawmakers sent to the ballot what became Amendment 4. In addition to requiring majorities in all eight congressional districts, it includes provisions aimed at prohibiting foreign donations to campaigns, requiring public hearings for proposed ballot initiatives and making the text of initiative petitions available at polling places. The proposal does not raise the bar to approve initiative petitions changing statutes.
"When this opportunity came about, we saw it as a once-in-a-generation opportunity to get us back to an improved process for how our constitution is amended here in Missouri," Hawkins said.
Backers of Amendment 4, such as Pemiscot County resident Barry Bean, have said they don't like how the Missouri Constitution has essentially become a document of statutory provisions that the legislature can't alter. They also contend that well-funded interest groups can persuade voters to approve favorable regulatory frameworks – as they contend happened in the cases of legalized sports betting and marijuana.
"I guess I'm old school enough to still think the constitution ought to be basically to determine the form of government and for big, broad principles," said Bean, whose father, Otto Bean, and brother, Jason Bean, served in the Missouri legislature. "Basic human rights that belong there, but not things like bingo or gambling or marijuana that should be in statutes so that they could be modified and changed as times and situations change."
Detractors of Amendment 4 point out that groups used the initiative petition process to expand Medicaid and legalize sports betting because the legislature wouldn't act. And they also say the proposal would allow a small percentage of the population to essentially veto a constitutional amendment with broad support.
"I just don't understand my rural neighbors' sense of grievance that they always think they're being left behind when the Republican legislature has controlled our state for 25 years, largely due to rural voters," said Boone County resident Kevin Heyen, who grew up on a farm in a town of 300 people. "Their vote counts the same as everybody else. Why do they think their vote should be weighted to count more just because they don't like the outcome of recent elections?"
Amendment 4 opponents also push back against the idea that only voters in Kansas City and St. Louis can approve ballot items, especially since the 2024 abortion legalization push passed in places like St. Charles and Buchanan counties.
"The initiative petition is a very powerful tool for the citizens of Missouri to use when we want certain laws to take place," said Cindy Austin of St. Charles County, who helped gather signatures for the 2024 amendment legalizing abortion. "It requires signatures from six of the eight congressional districts. So it's not just St. Louis, Kansas City."
Amendment 4 foes have also assailed how the measure allows legislative-directed constitutional proposals to only pass with a majority vote.
While Amendment 4 supporters say ballot items sent to voters from the legislature have to go through a rigorous process, detractors point out that Senate Republicans sent the plan to voters without a single moment of debate on the floor.
"It's laughable," said Scott Charton, a spokesman for the group Missourians for Fair Governance, which is opposing Amendment 4. "If there had been that discussion on the floor, some big problems in Amendment 4 would have been found. And I'll give you an example of this. Amendment 4 purports to address cracking down on petition fraud. Well, we currently have a law on petition fraud in Missouri, and it sets a penalty that prosecutors can do right now of $10,000 with petition fraud. Inexplicably, Amendment 4 reduces that to $1,000."
November fight approaching
Amendment 4's opposition campaign is getting serious financial backing from the Missouri Association of Realtors and organizational support from labor unions upset by how the legislature often overturns or tries to overturn voter-approved initiatives.
Many of those groups are also fighting Amendment 5, which would allow the legislature to expand sales and use taxes as a way to get rid of the income tax. If that plan fails, it could decrease the chances of Amendment 4 passing.
"I think there's just a lot of anger and mistrust in the government, so that's spreading through everything," said Wayne County resident Vinnie Clubb, an Amendment 4 backer.
Regardless of what happens to Amendment 4, the fight over the future of the initiative petition process could continue into the fall.
That's because Missourians will likely decide on a plan known as Respect Missouri Voters, which would make it more difficult for the legislature to overturn ballot items that residents approve.
Hummel, who helped gather signatures for that initiative, said the failure of Amendment 4 could provide momentum for the plan.
If passed, Respect Missouri Voters would bar the legislature from making significant changes to the initiative petition process including raising the threshold needed to pass a constitutional amendment.
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