The Supreme Court appeared closely divided Monday over the Navajo Nation’s effort to keep alive a lawsuit seeking more water for a reservation in Arizona, as the tribe told the justices that the federal government had an obligation to provide access to water sources.

The Navajo Nation contends that an 1868 treaty promised both land and water sufficient for the Navajos to return to a permanent home in their ancestral territory. That wades into the contentious history of divvying up the dwindling flow of the Colorado River among the states in that river’s basin.

Shay Dvoretzky, an attorney for the tribe, told the justices Monday that the Navajo should be able to pursue a lawsuit to make the U.S. government live up to the treaty that Congress approved more than 150 years ago.

“The right to water would be meaningless if the government as trustee doesn’t also have an affirmative duty as the trustee to ensure that the water is available to the beneficiary of the trust,” Dvoretzky said.

Several conservative justices questioned the decision in the case by the U.S. Court of Appeals for the 9th Circuit, which would allow the tribe to continue a long-running legal effort. And they questioned how the Navajo lawsuit fits in with existing agreements and litigation over water from the Colorado River known as the “Law of the River.”

Justice Brett M. Kavanaugh suggested the courts may not be the best avenue for the tribe and that “rather than a multiyear journey, here, where really it’s not clear you can ever get what you really want out of the court system, as we’ve danced around today, we should leave it to Congress.”

Congress has had decades to address the tribe’s water needs and the federal government’s decision not to pursue water rights in the Colorado River, Dvoretzky responded, and has done nothing.

“We’ve been waiting half a century for the political branches to solve this problem for the nation. It hasn’t happened,” Dvoretzky said.

Government argument

The Biden administration, which appealed the 9th Circuit decision along with states led by Arizona, argued that the Navajo had no right to pursue the suit.

Frederick Liu, assistant to the solicitor general, argued that the United States never expressly accepted a responsibility to provide water to the tribe as part of the treaty. Liu said the government has already provided tens of thousands of acre-feet of water and substantial investments in water infrastructure.

“Just as the 1868 Treaty didn’t impose on the United States a duty to build roads or bridges, or to harvest timber, or to mine coal, the 1868 treaty didn’t impose on the United States a duty to construct pipelines, pumps or wells to deliver water,” Liu said.

Liu said siding with the Navajo could upend relations with tribes nationwide and impose an “amorphous duty” to address water needs in about 500 reservations.

That argument ran into questions from Justice Neil M. Gorsuch, who compared the 1868 treaty to a contract. If someone promised a permanent homeland that included agricultural use in what turned out to be the Sahara Desert, “You don’t think that’s a breach of good faith and fair dealing?” Gorsuch said.

“I don’t think it would state a claim” for relief in court, Liu said.

Justice Elena Kagan and other justices on the liberal wing of the court questioned why the government would have to “expressly accept” an obligation to a tribe like providing water.

“I’m not getting it. If there is a contract and the contract gives a right to one party, then just by the nature of how rights work, it gives a duty to the other party,” Kagan said.

Long history

The tribe first filed the federal suit in Arizona against the Department of the Interior in 2003, seeking a ruling on water rights for the reservation. The reservation today spans millions of acres across Utah, Arizona and New Mexico.

Over the years the litigation has changed, and in 2021 a 9th Circuit panel ruled the Navajo Nation could file a third amended complaint alleging a breach of trust tied to the 1868 treaty with the United States.

Arizona has argued the suit was an end-run around the decades of agreements surrounding the limited water provided by the Colorado River.

Rita Maguire, arguing Monday on behalf of Arizona, said the tribe has effectively argued for the federal government to assert water rights over the Colorado rather than do so through the existing court process.

“Throughout the 20 years of litigation on this case, there’s only been one source of water identified. That’s the Lower Colorado River,” Maguire said.

The Supreme Court has heard multiple disputes between states and the federal government over water in the Colorado River, stretching back to 1952.

Congress has mandated the creation of an interstate plan to govern apportionment of the river’s water since 1928. Over the course of years, Congress and the courts set up a structure where each state got certain amounts of water each year and the federal government would divvy up reductions in dry years.