September 23, 2026

On September 23, 2026, the National Congress of American Indians (NCAI) and the Inter Tribal Association of Arizona represented by the Native American Rights Fund (NARF) filed an amicus brief in Tohono O’odham Nation v. Mullin, a case currently before the U.S. Court of Appeals for the District of Columbia Circuit challenging the federal government’s planned construction of a border wall through the Tohono O’odham Nation’s reservation in Arizona.

The brief represents Tribal voices in Arizona and across Indian Country that are alarmed by the federal government’s trespass on the Tohono O’odham Nation’s reservation and are opposed to this unlawful infringement on Tribal sovereignty.

“Tribal Nations were sovereign long before the formation of the United States, and today we  continue to exercise sovereignty over our lands,” said NCAI President Mark Macarro. “The administration’s actions reflect a blatant disregard for the sovereignty of the Tohono O’odham Nation. Indian Country stands with the Nation as it seeks to hold the federal government accountable.”

“Tribal Nations have a unique relationship with the federal government. Part of this relationship imposes a duty on the United States to steward and protect Tribal Nations’ land bases. The federal government’s actions on the Tohono O’odham Nation’s reservation are a dereliction of the duties the United States owes to Tribal Nations,” said NARF Staff Attorney Mitchell Forbes.

The amicus brief details the many instances where Tribal Nations have successfully sued trespassers in order to protect their lands from illegal encroachment and the unique role of the United States in protecting Tribal homelands — which makes the federal government’s trespass on Tohono O’odham land especially alarming.

“Historically, the courts have recognized that trespass claims are essential in protecting Tribal lands and interests and maintaining Tribal sovereignty,” said NARF Attorney Joel West Williams. “This filing shows that Tribal Nations are again unified in defending their lands from invasion and protecting their sacred places from haphazard destruction.”

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