Arizona Republicans Lose Grand Canyon Monument Lawsuit After 9th Circuit Rules Claims Were Speculative

A federal appeals court has rejected a lawsuit from Arizona legislative leaders seeking to overturn a national monument near the Grand Canyon, ruling that their claims of harm were speculative and that they lacked legal standing to bring the challenge.

The U.S. Ninth Circuit Court of Appeals unanimously agreed with a lower court ruling made more than a year ago, dismissing the legal challenge to the Baaj Nwaavjo I'tah Kukveni — Ancestral Footprints of the Grand Canyon National Monument.

The monument protects nearly 1 million acres of federal land surrounding the Grand Canyon to honor the ancestral homelands of local Native American tribes. It was designated by President Joe Biden in 2023 as part of his executive order expanding federal protection of Indigenous lands.

Who Filed the Challenge

The plaintiffs in the lawsuit include:

• State Senate President Warren Petersen, R-Gilbert
• House Speaker Steve Montenegro, R-Surprise
• State Treasurer Kimberly Yee, Republican
• Mohave County
• Colorado City
• City of Fredonia

The Arizona Legislature had argued the monument impeded its ability to govern state land and would harm the state's economy.

Why the Court Ruled Against Arizona

The three-judge panel on the 9th Circuit Court of Appeals wrote that all of the harms claimed by the plaintiffs were speculative. The court's memorandum ruling included several key points:

• The monument proclamation does not restrict state land — the Legislature still retains control over state land
• The monument does not change water rights or restrict cities' water access
• Claims about loss of uranium mining revenue were dismissed because mining bans are set to expire in 2032, making claims about future economic conditions too uncertain
• Energy price concerns were rejected as depending on many unknown variables

The court specifically addressed the plaintiffs' argument that the monument would cause local governments to lose tax revenue from uranium mining that could take place once the 2012 mining ban expires. The judges wrote that this reasoning was too speculative as to whether the right economic conditions and incentives for uranium mining would exist so far into the future.

What Arizona Officials Are Saying

Senate President Petersen told The Center Square he was "sad to see the 9th Circuit kicked the can down the road." He added:

"The court did not address whether the Biden administration had the right to create this massive national monument around the Grand Canyon. It simply ruled that our challenge came too soon."

Petersen said Arizona families "should not have to wait years while our land and economic opportunities remain locked up," and noted the plaintiffs are actively working with the Trump administration to undo the monument.

Attorney General Kris Mayes Supports the Ruling

Kris Mayes, Arizona's attorney general, said the ruling was a "victory for the people of Arizona and for the Indigenous communities whose ancestral homelands are protected by this monument."

Mayes, who was an intervener in the case, added she was "proud to have stood up to defend these sacred and important lands."

The Colorado River Indian Tribes Celebrate the Decision

The Colorado River Indian Tribes (CRIT) is praising the federal appeals court decision, calling it a win for tribal stewardship and protection of the Colorado River.

CRIT Chairwoman Amelia Flores and various Tribal Leaders have declared their support of the Baaj Nwaavjo I'tah Kukveni National Monument.

"The national monument protects the ancestral lands of our people," Flores said. "It protects the Colorado River, it protects the land, and it protects our way of life."

CRIT Chairwoman Amelia Flores and various Tribal Leaders have declared their support of the monument, praising the court's decision to uphold tribal stewardship and protection of the Colorado River.

What This Means Going Forward

The ruling upholds a decision by a U.S. district court in Arizona that rejected the plaintiffs' original legal challenge in January 2025. The 9th Circuit court dismissed the case because judges found the plaintiffs lacked legal standing.

State Senate President Petersen said the state Republicans "will continue fighting to protect Arizona's economy, jobs, and state sovereignty" from what they call an expansive federal land lock-up, including through any available avenues at the federal level.

Petersen noted the plaintiffs are actively working with the Trump administration to undo the monument, suggesting the case could be pursued again at the federal level.

The Monument's Purpose

The Baaj Nwaavjo I'tah Kukveni — Ancestral Footprints of the Grand Canyon National Monument — protects federal land surrounding the park to honor the ancestral homelands of local Native American tribes. The monument includes areas with significant cultural and historical importance to tribes including the Navajo, Hopi, and other Indigenous peoples of the region.

The 9th Circuit court noted in its ruling that the monument proclamation does not change water rights or restrict cities' water access, and that the Legislature still has control over state land.

Legal Context

The plaintiffs had argued the monument would cause local governments to lose tax revenue from uranium mining that could take place once the 2012 mining ban expired in 2032. The 9th Circuit judges dismissed this claim, writing that the reasoning was too speculative as to whether the right economic conditions and incentives for uranium mining would exist so far into the future.

The court also rejected arguments about water supply restrictions, noting the national monument proclamation does not change water rights or restrict cities' water access.

Next Steps

State Republicans say they will continue exploring legal options to challenge the monument. Senate President Petersen indicated they are working with the Trump administration to pursue further legal avenues.

The monument remains intact, and the federal government maintains control over the nearly 1 million acres of protected land surrounding the Grand Canyon.