The battle over Medicaid expansion in Missouri reached a new boiling point Thursday as Gov. Mike Parson, a Republican, announced that the state will not implement expansion, in defiance of a ballot measure passed by voters last year.

The decision stems from Republican state lawmakers' refusal to appropriate funds for the expansion to the state's Medicaid program, called MO HealthNet, in the state budget bill passed last week.

"Although I was never in support of MO HealthNet expansion, I always said that I would uphold the ballot amendment if it passed," Parson said. "However, without a revenue source or funding authority from the General Assembly, we are unable to proceed with the expansion at this time and must withdraw our state plan amendments to ensure Missouri's existing MO HealthNet program remains solvent."

The decision is certain to face legal challenges, which Parson acknowledged in comments to reporters after the announcement.

"I don't want to speculate what the courts will do, because there's a lot of moving parts to this," he said. "You know there's going to be court actions on both sides, I'm sure."

Democrats in Missouri, including the top Democrat in the statehouse and multiple mayors, immediately criticized the governor's decision.

"By backtracking on implementation of Medicaid expansion, Gov. Parson is breaking his promise to the people of this state and violating his oath to uphold the Missouri Constitution," said House Minority Leader Crystal Quade. "Medicaid expansion will still happen as the constitution requires, but because of the governor's dishonorable action, it will take a court order to do it."

The American Cancer Society also urged the governor to reconsider.

"Cancer patients cannot wait for legal battles to access the life-saving coverage that Medicaid expansion provides," the group's government relations director in Missouri, Emily Kalmer, said in a statement.

Missouri's current Medicaid program is one of the most restrictive in the United States. To qualify, a family of three must earn less than 21% of the federal poverty level — in 2021, that amount is just $5,400. Childless adults cannot qualify at all.

Last August, 53% of voters in this deep-red state approved a ballot measure to raise the limit to 138% of the federal poverty level, roughly $17,774 for a single adult and $37,570 for a family of four. It would have made Missouri the 38th state to expand Medicaid access under the Affordable Care Act.

An analysis by Washington University in St. Louis found that about 271,500 Missourians were likely to enroll in the expanded coverage, which was set to take effect July 1, 2021.

The same study found the Medicaid expansion was most likely to result in budget savings for the state. That counterintuitive finding, which has been observed in other states, is explained by demand shifting from other public programs that are more expensive for the state, as more people opt for expansion coverage, which is largely funded by the federal government.

The Affordable Care Act requires the federal government to cover 90% of the cost of expanded eligibility.

On top of that, the new federal stimulus package signed by President Biden in March pitches in another 5% as an incentive for states that had yet to expand Medicaid when the bill was enacted, including Missouri. That would have saved the state an additional $1 billion, according to a federal estimate.

But Republicans in Missouri have long complained about what they say is an unaffordable expense, even as the state has an estimated $1.1 billion budget surplus.

The announcement comes just two days after Parson announced that Missouri would join several other Republican-controlled states in ending its participation in federal pandemic-related unemployment benefits.

"What did hard working Missourians and those looking for work do to have Missouri's majority party deny them increased wages, survival subsidies (funded by the feds), and healthcare (funded by the feds)?" wrote Quinton Lucas, the Democratic mayor of Kansas City, on Twitter. "For the many of us who have known struggle, it's just cruel."

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