Jackley, lawmakers split on Medicaid ballot measure

Conflicting explanations

South Dakota voters face competing interpretations of Amendment I, a proposed constitutional change on the Nov. 3 ballot. Attorney General Marty Jackley’s ballot title says the measure repeals expanded Medicaid coverage if the federal government’s share of expansion costs falls below 90%. His explanation also says the coverage ends under that condition.

Legislators who put the amendment on the ballot say that description goes too far. Rep. Will Mortenson, a Fort Pierre Republican who sponsored the legislation, says the amendment would remove the state Constitution’s requirement to maintain expansion if federal support declines. Under his interpretation, lawmakers could then decide whether to keep, change or end the expanded coverage.

Lt. Gov. Tony Venhuizen, who sponsored the proposal while serving as a legislator in early 2025, also disagrees with language suggesting the result would be automatic.

What Amendment I would change

South Dakota voters added Medicaid expansion to the state Constitution in 2022. The policy extended eligibility to adults with incomes up to 138% of the federal poverty level, beyond groups already covered, including children, older adults and people with disabilities.

The federal government currently pays 90% of states’ Medicaid expansion costs. Because South Dakota’s expansion requirement is constitutional, voters must approve any change to it.

Lawmakers advanced Amendment I during the 2025 legislative session because of concern that the federal contribution could decline. They estimated that a reduction in federal support to 70% would leave South Dakota responsible for about to maintain the expansion.

The disagreement means voters must weigh the attorney general’s explanation against the sponsors’ description of how the amendment would operate. The central question is whether a drop below 90% would itself end the constitutional expansion requirement or instead open the issue for legislative action.