Members of the Omaha Tribe of Nebraska participated in Spiritual Ride on the reservation on January 16, 2016, in advance of oral arguments before the U.S. Supreme Court. Photo from Facebook

The Omaha Tribe secured a major victory on Tuesday when the U.S. Supreme Court rejected a closely-watched challenge to its reservation boundaries.

After just two months of deliberations in the long-running case, the justices determined that Congress did not diminish the reservation when it opened some areas to non-Indians. The ruling was unanimous and its confirms that the village of Pender has always been Indian Country.

"We hold that Congress did not diminish the reservation in 1882 and that the disputed land is within the reservation’s boundaries," Justice Clarence Thomas wrote for the court.

The underlying dispute, though, is not quite over. The village contested the reservation boundaries because the tribe imposed a liquor tax on non-Indian owned businesses in the community. That issue was not before the court so it was not resolved, Thomas noted.

Indianz.Com SoundCloud: U.S. Supreme Court oral arguments in Nebraska v. Parker

Still, the ruling represents a big win for the tribe and its efforts to assert sovereignty over the entire reservation. Chairman Vernon Miller happened to be in Washington, D.C., when the court released the decision.

"I'm heading to the Supreme Court now to let out a war hoop!" Miller wrote on Twitter.

In a sign of the seriousness of the matter, Miller and the entire tribal council attended oral arguments at the high court on January 20. The hearing appeared to go well, with even the late Justice Antonin Scalia, who is typically hostile to Indian interests, questioning whether the reservation was diminished.

"To say, you know, a later Congress did thus and so, and therefore the earlier Congress -- when it enacted a particular statute, must have diminished -- that doesn't make any sense," the late justice said at the time. Scalia passed away on February 13 at the age of 79.

Leaders of the Omaha Tribe of Nebraska stand in front of the U.S. Supreme Court on January 20, 2016, after oral arguments in Nebraska v. Parker. Photo form Facebook

The vacancy on the court likely did not play a role in the outcome of the case and the fact that the decision was assigned to Thomas, who almost always went along with Scalia, shows that the tribe presented a particularly strong argument. The tribe had won in the federal court and in the 8th Circuit Court of Appeals.

The unanimous ruling also helps to put another Indian law development in context. On Monday, the justices refused to hear a case that questioned the sovereignty of the Ute Tribe of Utah, where local and state officials have continue to dispute the reservation boundaries despite losing a slew of cases dating back to the 1990s.

Together, the cases indicate the high court's reluctance to disturb its precedents in reservation boundary disputes. The village of Pender and the state of Nebraska tried to do that by arguing that the mere presence of non-Indians in the area amounted to a "de facto diminishment."

But Justice Thomas confirmed the court's precedents in cases like Hagen v. Utah -- which involved the Ute Tribe -- and South Dakota v. Yankton Sioux Tribe require a fuller look at the circumstances. The mere presence of non-Indians isn't enough to go against Congressional intent, he noted.

"Only Congress has the power to diminish a reservation. And though petitioners wish that Congress would have 'spoken differently' in 1882, 'we cannot remake history,'" Thomas wrote, citing DeCoteau v. District Court for the Tenth Judicial Court, an even older boundary case.

Supreme Court Decision:
Nebraska v. Parker (March 22, 2016)

Supreme Court Documents:
Oral Argument Transcript | Docket Sheet No. 14-1406 | Questions Presented | Hearing List: January 2016

8th Circuit Decision:
Smith v. Parker (December 19, 2014)

Federal Court Documents:
Status Report [Includes tribal court decision] | Court Order

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