While Arkansas looks to replace its first-of-a-kind model for expanding Medicaid, Gov. Asa Hutchinson urged lawmakers to renew it through 2016.
Most states refused to keep funding a pay raise for Medicaid doctors this year, but the first national study of the policy shows it increased low-income patients' access to primary care.
The case could halt private lawsuits against state Medicaid agencies over doctor pay.
The state has recently taken more drastic steps than any other to transform its health and criminal justice systems to address the nationwide epidemic.