The answer to the question could have vast implications for criminal prosecutions and for commerce.
The Supreme Court heard arguments on Monday about whether much of eastern Oklahoma is an Indian reservation, a question that could have enormous consequences for the area’s 1.8 million residents in matters of criminal justice and commerce.
The argument touched on the dark history of the nation’s treatment of Native Americans and the practical implications of a ruling that Congress had never clearly destroyed the sovereignty of the Muscogee (Creek) Nation over the area, covering about half the state.
“Congress never terminated the Creek reservation and never transferred federal jurisdiction to Oklahoma,” said Ian H. Gershengorn, a lawyer for Jimcy McGirt, a member of the Creek Nation who was convicted of sex crimes against a child by state authorities in the Nation’s historical boundaries. Mr. Gershengorn argued that only federal authorities were entitled to prosecute his client.
Mithun Mansinghani, Oklahoma’s solicitor general, took the opposite view. “Oklahoma has jurisdiction over the eastern half of the state because it was never reservation land,” he said, “and it’s certainly not reservation land today.”
Several justices said they were concerned about a decision that would require federal authorities to investigate and prosecute crimes in eastern Oklahoma.
