Murphy went back to court with that claim and another: Even if the road was not allotment land, the petition argued, it was still Indian country. Why? Because, the lawyers argued, all the surrounding land was still part of the huge MCN reservation guaranteed under an 1832 treaty with the United States.

Read: The Blackfeet brain drain

In November 2017, the U.S. Court of Appeals for the Tenth Circuit agreed.

After 175 years, it held, the Creek Reservation remained intact.

How can that be? In 1832, President Andrew Jackson pushed through the policy of “removal” of Indian nations from the eastern U.S., which destroyed the historic land base of the “civilized tribes.” He promised the tribes new land in the West to be theirs “as long as the grass grows or the water runs, in peace and plenty.” After the Trail of Tears, the U.S. signed a treaty that “solemnly guarantied” the new reservation lands in what is now Oklahoma.

Many tribes elsewhere have found to their regret that Congress is permitted to decide that the grass ain’t growing any more. It can abrogate some or all treaty obligations—and even “terminate” a tribe altogether. But case law says there is a “clear statement” rule: If Congress wants to end a reservation, it has to say so.

It apparently did not. The Tenth Circuit said it couldn’t find any statute ending the reservation created by the Creek Nation’s treaty of 1832. Nor could it find evidence that Congress at any time showed a desire to abolish the reservation. Applying a 1983 precedent called Solem v. Bartlett, the court reasoned that all 3 million acres, whether owned by Indians, non-Indians, the federal government, or state or city governments, remained “Indian country.” Under the Major Crimes Act, Murphy’s conviction was void and he was entitled to a retrial in federal court.

Chief Judge Timothy Tymkovich, in a separate concurrence, agreed that the Solem opinion required the court to hold against Oklahoma. However, he said dryly, the high court might want to look at Solem again. “This challenging and interesting case makes a good candidate for Supreme Court review,” he wrote. The Supreme Court granted certiorari in May.

Before the Court, Oklahoma argues that the contemptuous treatment of the tribe by the state and federal government after allotment makes a formal statute unnecessary. “Congress’s breach of its treaty promises of communal land ownership … and tribal self-government, combined with the creation of Oklahoma, amply overcomes the presumption that Congress does not lightly abrogate its treaty promises or diminish a reservation,” the state argues.

Supporting Oklahoma in an amicus brief, the federal government notes that Congress “broke up the Creek Nation’s lands, abolished its courts, circumscribed its governmental authority, applied federal and state law to Indians and non-Indians alike in its territory, provided for allotment of almost all of its communal lands to individual tribal members, distributed tribal funds to individual Indians, and set a timetable for dissolution of the Tribe.” Thus, “Congress did not intend for the new State of Oklahoma to include a massive Creek reservation throughout which the Tribe and the federal government would have jurisdiction to the exclusion of the State over all crimes involving Indians.”