Biden Monuments Case to Focus on State Lawmakers’ Ability to Sue

Upcoming arguments in a challenge to the White House’s ability to create national monuments could determine whether state legislatures can bring lawsuits over the objections of the state’s governor and attorney general.

The US Court of Appeals for the Ninth Circuit is set to hold oral arguments Feb. 3 in Arizona State Legislature v. Biden, in which Republican lawmakers in Arizona sidestepped the Democratic state governor and attorney general in challenging Baaj Nwaavjo I’tah Kukveni-Ancestral Footprints of the Grand Canyon National Monument. Former President Joe Biden created the monument on federal land in 2023.

The appeals court panel will grapple with whether state lawmakers have standing to challenge the White House’s use of the Antiquities Act to create national monuments, and a decision in their favor will reverberate across the country.

“If that happens, you’re going to see a lot more litigation on many fronts,” as legislatures begin challenge federal actions a governor supports, said Dave Owen, an environmental law professor at the University of California College of the Law in San Francisco.

The US District Court for the District of Arizona dismissed the lawsuit in 2025, ruling that the lawmakers don’t have standing to sue, and the court has no subject matter jurisdiction over the case. Republicans control both houses of the Arizona State Legislature, but Gov. Katie Hobbs is a Democrat who supports national monuments.

The case, alongside Garfield County v. Biden, a pending Tenth Circuit case focused on two Utah national monuments, could determine judicial review over national monuments. Many GOP-controlled states and Republican lawmakers have criticized presidential use of the Antiquities Act to block oil, gas, and mining development on millions of acres of federal land as an abuse of the law.

Focus on Standing

Legal analysts say they expect the Ninth Circuit to avoid the case’s Antiquities Act claims and focus mainly on standing.

The case is “one to watch” because standing is a “doctrine in flux,” said Andrew Mergen, an environmental law professor at Harvard Law School.

He says the monuments dispute in the case is more of a policy issue than a legal debate, making it difficult for the plaintiffs to prove standing.

“The legislature seeks to stand in for economic interests, but that makes these alleged harms doubly remote,” Mergen said. “The district court should be affirmed but the Supreme Court has not always been consistent on standing issues. I suspect that if the legislature loses here, they will seek Supreme Court review.”

The impact of the case could be limited, said Deborah Sivas, director of the Environmental and Natural Resources Law and Policy Program at Stanford Law School.

“It presents a unique standing challenge, where the legislative majority is at odds with the governor and state AG,” she said, referring to Arizona’s attorney general. “In most states these days, the same party holds both the legislature and the executive branches—and the state AG would not face the same injury challenge that the Arizona legislature does here.”

The Merits

If the Ninth Circuit grants the legislature standing, the case will be remanded to the district court, which will address the merits of the case, said Jason Searle, senior staff attorney for the Native American Rights Fund, which represents several Arizona tribes.

The Arizona lawmakers claimed in their lawsuit that Biden’s creation of the Ancestral Footprints monument harmed their jurisdiction over nearby state trust lands. However, Biden designated the monument on existing federal land around Grand Canyon National Park and did not transfer ownership of any land.

“We want to watch how vigorously the administration will defend the monument,” Searle said.

President Donald Trump has been mostly silent on national monuments since taking office in 2025, but he has a record of opposing them. The first Trump administration shrank two Utah national monuments, a move Biden reversed. The Justice Department in a May 2025 opinion declared that Trump has the right to abolish monuments under the Antiquities Act, which grants the president one of his “most sweeping unilateral powers.”

Harvard’s Mergen said the plaintiffs in the case appear to think they’ve got a shot at winning because US Supreme Court Chief Justice John Roberts has said he’s skeptical of the recent uses of the Antiquities Act.

Roberts, in Massachusetts Lobstermen’s Association v. Raimondo, suggested the scope of presidential power under the Antiquities Act could be limited.

Most recent presidents, including Trump, have created monuments under the Antiquities Act. But Democratic presidents are known for carving monuments out of large acreages, including President Bill Clinton, who created Utah’s Grand Staircase-Escalante National Monument, and President Barack Obama, who created Utah’s Bears Ears National Monument. Together those monuments total more than 3 million acres.

Biden created 10 national monuments in nine states, totaling about 2.3 million acres.

The stakes in the Arizona case are high for tribes, which consider the Grand Canyon area sacred land, Searle said.

“It’s the ancestral home of these tribes—places where they’ve conducted spiritual, religious, and cultural practices since time immemorial,” he said.

James Otis Law Group of St. Louis, Mo., represents the plaintiffs. The Justice Department represents the federal government. The Arizona Attorney General’s office represents the state.

The case is Ariz. State Legis. v. Biden, 9th Cir., No. 25-1370, arguments 2/3/26.