Supreme Court rules that a large portion of Eastern Oklahoma is Native American territory

• The Supreme Court ruled in a 5-4 Thursday decision that a large portion of Eastern Oklahoma must be considered Native American tribal territory under the Major Crimes Act.
• In the case, McGirt vs. Oklahoma, the Court was tasked with resolving whether the state of Oklahoma has the standing to prosecute crimes that take place on lands Congress designated to be "Indian Country."
• Under the parameters of the Major Crimes Act, only tribal authorities and the federal government – not state-level authorities — can prosecute crimes committed on Native American reservations.

The US Supreme Court ruled in a 5-4 decision on Thursday that a large portion of Eastern Oklahoma must be considered Native American tribal territory under the Major Crimes Act, meaning all criminal cases in that jurisdiction must be prosecuted by federal authorities.

Justice Neil Gorsuch wrote the majority opinion, joined by Justices Ruth Bader Ginsburg, Stephen Breyer, Sonia Sotomayor, and Elena Kagan. Chief Justice John Roberts and Justices Clarence Thomas, Brett Kavanaugh, Samuel Alito, and Clarence Thomas dissenting.

In the case, McGirt vs. Oklahoma, the Court was tasked with resolving whether the state of Oklahoma has the standing to prosecute crimes that take place on lands Congress had previously designated to be "Indian Country." The relevant land includes 18 million acres in Eastern Oklahoma, including the city of Tulsa, and is home to 1.8 million residents.

In 1866, the US Congress enacted a law establishing a large portion of Eastern Oklahoma as Native American territory belonging to the Cherokee, Muscogee, or Creek, Chickasaw, Choctaw, and Seminole tribes.

The plaintiff in the case, Jimmy McGirt, is a member of the Seminole Nation who was convicted under Oklahoma state law of sexual offenses against a minor in 1996, crimes committee on Creek Nation territory. He challenged his conviction in court as being invalid under the Major Crimes Act.

Under the Act, only the federal government and tribal authorities, not individual states, can prosecute crimes committed by Native Americans on federally-designated Native American reservations and land.

His attorneys argued in court that since Congress did not formally disestablish the reservation that Congress established, the state of Oklahoma does not have jurisdiction to prosecute or try McGirt under state law, and McGirt must be retried in federal court.

The state of Oklahoma, however, argued that the tribal lands that Congress designated as Indian Country in 1866 were, in fact, dis-established with the 1906 Oklahoma Enabling Act, in which Congress allowed all of Oklahoma to be admitted to the union as one state.

Gorsuch and the court's liberals sided with McGirt in ruling that since Congress never properly dis-established the sovereignty of the Creek Nation, the land qualifies as Indian Country and the relevant portions of the Major Crimes Act apply.

"The federal government promised the Creek a reservation in perpetuity. Over time, Congress has diminished that reservation. It has sometimes restricted and other times expanded the Tribe's authority. But Congress has never withdrawn the promised reservation," Gorsuch wrote in his opinion.

He added: "If Congress wishes to withdraw its promises, it must say so. Unlawful acts, performed long enough and with sufficient vigor, are never enough to amend the law."

In 2018, The Court also heard arguments in a similar case over the status of Eastern Oklahoma, Sharp v. Murphy. In that case, a member of the Creek Nation, Patrick Murphy, argued that his 2000 murder conviction and death sentence in a state court was invalid because the crime took place within Muscogee Nation territory.

Gorsuch, who had ruled on Murphy's case as a judge on the 10th Circuit Court of Appeals, recused himself from arguments in the Murphy case, and the 8-justice court hearing arguments appeared to be deadlocked.