Kelsey Reichmann

WASHINGTON (CN) — A century-old fight in the arid American Southwest converged at the Supreme Court on Monday where the justices examined if the government is responsible for giving a tribe the ability to live on the land it granted them.

The Navajo Nation is asking the justices to uphold a lower court ruling that would force the federal government to account for their water rights to the Colorado River. After nearly two hours of oral arguments, some justices appeared sympathetic to the tribe’s fight for resources.

“Clearly there is a duty to provide some water to this tribe,” said Justice Neil Gorsuch, who himself hails from the West and is noted for his experience in federal Indian law.

Gorsuch pointed to the government’s promise, in creating a reservation for the Navajo, that it would provide the tribe with a permanent home. He questioned how such a promise could be fulfilled without water.

Justice Elena Kagan said if the government gave the Navajo Nation rights to water in its treaty, then it created a duty to supply them with it. Without that duty, the Obama appointee said, there would be a gap in what was promised versus what was delivered.

Still other members of the court, particularly Gorsuch's conservative colleagues, appeared reluctant to sign off on sticking the government with a duty to provide the Navajo with water rights. Justice Samuel Alito worried about the potential domino effect the court’s ruling would create for other tribes’ rights.

“What would be the nationwide impact of such a ruling,” the Bush appointee asked.

By the government's tally, there are around 500 tribal reservations, and it has entered into about 30 water agreements since the late 1970s. If the court were to impose a duty, it might be obligated to take a second look at all of those issues.

Serving over 36 million people in the West, water from the Colorado River is a hot commodity. Touching five states, the river flows 1,300 miles through Colorado, Utah and Arizona, while also hitting borders that the Grand Canyon state shares with Nevada, which is also landlocked, and California.

Smack dab in the middle sits the Navajo Reservation, which received over 17 million acres of land in an 1868 treaty with the United States. While stretching across Utah, Arizona and New Mexico, the reservation also shares a border with the mainstream of the Colorado River and includes land within the upper and lower basins.

The tribe has settled its water rights with New Mexico and Utah but Arizona has held out. Citing a failure to protect their water rights, the Navajo Nation sued Arizona and the government in 2003, claiming the state violated the National Environmental Policy Act of 1969 and the government’s trust obligations to the tribe.

A decadeslong pause failed to produce successful settlement negotiations. In 2013, a federal judge dismissed the case. The Ninth Circuit issued a partial reversal, finding the Navajo Nation had a breach-of-trust claim.

The Ninth Circuit again revived the suit after another District Court dismissal. The government and states then turned to the Supreme Court to settle if the federal government had a duty to assess the Navajo Nation’s water needs. The court took up the case in November.

In 1908, the Supreme Court decided Winters v. United States, creating a doctrine that says when Congress reserves land — such as in a reservation — it also reserves the water to support that land. The Navajo relied heavily on the Winters doctrine in their arguments before the court.

“The United States has taken on the fiduciary obligation to ensure our Winters rights,” said Skadden Arps attorney Shay Dvoretzky, representing the Navajo. “The United States itself believes that it holds the Winters rights in trust. The very first step that it needs to take is to assess and figure out its plan for how those Winters rights will be satisfied and met. And so it is the United States' duty to figure out where that water ought to come from.”

A previous Supreme Court ruling out of Arizona could shape the current battle before the justices. Sixty years ago in Arizona v. California, the court put the interior secretary in charge of managing the water division between Arizona, California and Nevada. Arizona also provided some tribes with water rights, but the Navajo were left out.

The justices questioned why the Navajo Nation was not included in Arizona and noted the government’s effort to block the tribe from intervening.

“The United States failed to assert Winters rights on your behalf and, in fact, blocked you from intervening for yourselves,” Justice Amy Coney Barrett told the nation’s attorney.

The government acknowledged its responsibility to provide the tribes with adequate resources, calling water just one stick in the bundle to which the Navajo were entitled.

“When the reservation was established it isn’t just land,” said Frederick Liu, assistant to the U.S. solicitor general.

Liu distinguished the government's promises to the Navajo from the issue at hand.

“This is not to say that the United States doesn't have a moral and political responsibility to address the Navajo Nation's water needs. … What the Navajo Nation cannot do, however, is to impose on the United States a duty that the government has never expressly accepted,” Liu said.