Every lower court that considered work-rules cases have blocked the controversial policy, including a federal appellate panel earlier this year. U.S. Court of Appeals for the District of Columbia Circuit, in an opinion authored by a Reagan appointee, found that Arkansas' work rules weren’t allowed under Medicaid law and that the Trump administration failed to consider how many people would lose coverage under the policy.

Nearly 20 states have received or sought the Trump administration’s permission for similar work rules, but virtually none of those policies have been active. Many were put on hold as the legal battle played out, and Utah paused its work rules because of the pandemic.

Even if the Supreme Court’s new 6-3 conservative majority eventually sides with Trump and overturns previous rulings, Biden's camp has indicated the incoming administration will reject requests for work rules and may even look to revoke existing approvals. That could draw resistance from states who have already received the Trump administration's permission. And a Supreme Court ruling upholding work rules could allow future Republican administrations to move forward with the policy.

Background: Work rules were a priority of CMS Administrator Seema Verma and the realization of a longtime Republican goal of making enrollment contingent on employment or schooling for many working-age adults. Verma and supporters of the work rules contended they would make Medicaid enrollees healthier by encouraging employment.

Many Republican state officials quickly welcomed the policy and sought out the Trump administration’s permission for waivers. Most were in Medicaid expansion states, but states that cover smaller populations of poor adults were also granted waivers, including Georgia, South Carolina and Wisconsin.

Democratic policymakers and patient advocates criticized the rules as simply a way to cull Medicaid rolls, which have grown by about 5 million to roughly 69 million during the pandemic. They said the work requirements were counter to Medicaid’s primary purpose of providing coverage.

In Arkansas, the first state to implement work rules in June 2018, more than 18,000 people lost Medicaid coverage in a few months before a federal judge struck down the policy. Only a fraction of those who lost coverage were able to find insurance elsewhere, according to state data.

What’s next: The Supreme Court is likely to hear the case early next year and issue a decision later in spring. Biden is expected to withdraw the Department of Justice’s support for the case, but the case would move forward since Arkansas and New Hampshire have also appealed.