Republican state Sen. John Lamping, the bill's author, contends the subsidies provided by the federal law are illegal and will eventually be rejected by the courts, the St. Louis Post-Dispatch reported Monday.
The subsidies help low- and middle-income Americans pay their health insurance premiums.
Missourians have twice voted against provisions of the Affordable Care Act, and Lamping said his bill was a way to "push back" against the law.
"Clearly, in Missouri, there's a very strong sense that they don't want this law," he said.
Democratic state Sen. Gina Walsh said the law is helping people get health insurance and that Lamping's bill would "just throw a wrench in the whole situation, slow everything down."
Lamping's proposal "might add more questions than answers," said Brent Butler, governmental affairs director for the Missouri Insurance Coalition.
A similar bill has been filed in the Missouri House. Neither proposal has been scheduled for hearings.
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