The Supreme Court on Thursday ruled that nearly half of the state of Oklahoma is part of the Muscogee Creek Indian Reservation.
The case was introduced to the Supreme Court by Jimmy McGirt, a Muscogee Indian who was convicted by a state court of raping a 4-year-old girl in Tulsa in 1997.
McGirt argued that the case should not have been tried in an Oklahoma court since the crime occurred on tribal land. He contended that residents of an Indian reservation fall under the jurisdiction of the federal courts.
The 5-4 decision, authored by conservative Justice Neil Gorsuch who sided with the four liberal justices, endorsed the Muscogee Nation's claim that only federal authorities can charge Native Americans who commit crimes on the land.
"Today we are asked whether the land these treaties promised remains an Indian reservation for purposes of federal criminal law," Gorsuch wrote. "Because Congress has not said otherwise, we hold the government to its word."
In his dissent, Chief Justice John Roberts warned that "decades of past convictions could be thrown out" due to the court's ruling.
"On top of that, the Court has profoundly destabilized the governance of eastern Oklahoma. The decision today creates significant uncertainty for the State's continuing authority over any area that touches Indian affairs, ranging from zoning and taxation to family and environmental law," Roberts added.