Mary Kathryn Nagle

Born in Oklahoma City, Nagle learned that history from her grandmother, who taught her as a child to respect the Supreme Court. She studied theater at Georgetown University and graduated summa cum laude from Tulane Law School. She clerked in Omaha for Judges Joseph F. Bataillon and Laurie Smith Camp of the federal district court in Nebraska, and in Austin for Judge Fortunato P. Benavides of the Fifth Circuit.

In 1879, in a federal court in Omaha, the Ponca chief Standing Bear won a ruling that an Indian was a person within the meaning of the law. Nagle wrote Waaxe’s Law, a play about the Ponca removal and Standing Bear’s journey. On September 16, 2011, when a bust of Standing Bear was unveiled at the federal courthouse in Omaha, Judge Bataillon introduced her as a former clerk of his and of Judge Smith Camp and spoke of her play; on December 12, 2012, Waaxe’s Law had a staged reading at the Newseum in Washington.

After four years as an associate at Quinn Emanuel Urquhart & Sullivan in New York, she became a partner at Pipestem Law, a firm whose work centers on tribal sovereignty and jurisdiction.

Sliver of a Full Moon

In 1978, in Oliphant v. Suquamish Indian Tribe, the Supreme Court held that tribal courts lacked criminal jurisdiction over non-Indians who commit crimes on tribal lands. The 2013 reauthorization of the Violence Against Women Act restored part of that jurisdiction, over non-Indians who commit domestic violence, dating violence or protection-order violations on tribal lands.

Nagle began writing Sliver of a Full Moon in April 2013, after a dinner with the lawyers Wilson Pipestem and Brenda Toineeta Pipestem; its title refers to the partial restoration. The play sets survivors’ testimony beside re-enactments of discussions between Native advocates and members of Congress, and many of the survivors, among them Lisa Brunner, Diane Millich and Cherrah Giles, play themselves. It was first performed in June 2013 at the National Indigenous Women’s Resource Center’s Women Are Sacred conference in Albuquerque, was read at the U.S. Capitol Visitor Center in March 2014, and was performed at the United Nations Church Center in September 2014 and at Yale Law School in March 2015, where Judge William A. Fletcher of the Ninth Circuit introduced it.

Briefs at the Threshold of the Court

In 2003 the Mississippi Band of Choctaw Indians’ Youth Opportunity Program placed a thirteen-year-old member of the tribe in an unpaid position at a Dollar General store on the reservation, on land held in trust for the tribe. In 2005 he sued the company and the store’s manager in the Choctaw tribal court, alleging that the manager had sexually molested him. On March 14, 2014, the Fifth Circuit, in an opinion by Judge James E. Graves Jr., held that “Dolgencorp’s consensual relationship with Doe gives rise to tribal court jurisdiction over Doe’s claims,” and the company took the case to the Supreme Court.

On October 22, 2015, Nagle filed a brief as counsel of record for the National Indigenous Women’s Resource Center and 104 other organizations, with Wilson K. Pipestem, Abi Fain and Sarah Deer. They told the Court that Native women are more likely to be battered, raped or sexually assaulted than any other population in the United States, that non-Indians commit most violent assaults on Native women and children, and that tribal courts had been barred since 1978 from exercising criminal jurisdiction over non-Indians. The Court’s Montana framework, they argued, “should not be construed to preclude the preservation of tribal self-government.” On June 23, 2016, an equally divided Supreme Court affirmed the Fifth Circuit, leaving the tribal court’s jurisdiction in place.

The Law Behind the Curtain

Arena Stage in Washington, which had commissioned it in 2015, staged Nagle’s play Sovereignty in January and February 2018. The play opens in 2013, as the Cherokee Nation puts the new law into effect, with Sarah Ridge Polson, a Cherokee lawyer, defending her nation’s right to prosecute a non-Native defendant accused of sexual assault before the Cherokee Nation Supreme Court, and it moves back and forth in time to John Ridge and the Treaty of New Echota. “Our tribal nations have an inherent right to protect our citizens,” Nagle said.

From 2015 to 2019 she was executive director of the Yale Indigenous Performing Arts Program. In August and September 2026 Three Bone Theatre staged Sovereignty at the Arts Factory in Charlotte and then, on September 11 and 12, at Cherokee Central Schools in Cherokee, North Carolina.

On the Far End

On February 11, 2020, Nagle filed a brief for the National Indigenous Women’s Resource Center and others in McGirt v. Oklahoma, which turned on whether the Muscogee (Creek) Reservation still existed. Under the 2013 law, restored tribal jurisdiction applied in Indian country; as Nagle and Sarah Deer later wrote, the brief explained “the gendered implications of the decision,” since a ruling against the reservation would complicate how the Muscogee Nation’s Lighthorse Police answered victims’ calls. On July 9, 2020, the Court held, five to four, that the reservation had never been disestablished. “On the far end of the Trail of Tears was a promise,” Justice Neil Gorsuch’s opinion began.

Her one-woman play On the Far End, whose title refers to the decision, follows the Muscogee leader Jean Hill Chaudhuri from her family’s history on the Trail of Tears and her grandfather’s allotment in central Oklahoma through her escape from a Native boarding school, her marriage to a Bengali scholar and her advocacy. It premiered at Round House Theatre in Bethesda, Maryland, in April 2023, with Nagle playing Chaudhuri, and Justice Gorsuch attended opening night. It was performed in Tulsa on July 9, 2023, the decision’s third anniversary, and The Old Globe in San Diego presented a reading, directed by Madeline Sayet, on January 17, 2026.

Highway 212

One night in February 2016, a Crow Police Department officer stopped beside a truck parked on U.S. Highway 212, a public right-of-way across the Crow Reservation in Montana. The driver appeared to be non-Native and had watery, bloodshot eyes, and two semiautomatic rifles lay on the front seat; the officer then found methamphetamine in the truck. The Ninth Circuit held that a tribal officer could not stop a non-Indian on such a road on reasonable suspicion alone; a violation of state or federal law had to be apparent.

On January 15, 2021, Nagle filed a brief as counsel of record for the National Indigenous Women’s Resource Center, eleven tribal nations and forty-four nonprofit organizations, arguing that forcing tribal police to wait until domestic violence became “obvious” or “apparent” “will cost lives.” On June 1, 2021, the Supreme Court unanimously held, in an opinion by Justice Stephen Breyer, that a tribal officer may temporarily detain and search a non-Indian on a public right-of-way through a reservation for potential violations of state or federal law. Denying that authority, Breyer wrote, “would make it difficult for tribes to protect themselves against ongoing threats.”

Indian Children and Their Nations

The Indian Child Welfare Act of 1978 sets federal standards for the removal of Native children from their families and for their placement. In 2013, as an associate at Quinn Emanuel, Nagle was on a brief, with Kathleen M. Sullivan as counsel of record, for current and former members of Congress defending the act in Adoptive Couple v. Baby Girl. Congress’s purpose in enacting it, they told the Court, was “to ensure the continued sovereign and political existence of the Indian tribes.”

When the act was challenged again in Haaland v. Brackeen, Nagle was counsel of record, with Sarah Deer and Shoney Blake, on an August 19, 2022 brief for the National Indigenous Women’s Resource Center, Stephanie Benally of the Navajo Nation, Sandy White Hawk of the Rosebud Sioux Tribe and eighty-eight organizations. “ICWA does not dictate outcomes; it is a procedural law,” they wrote, and they argued that no sovereign is better equipped to protect Native children than their own nations. On June 15, 2023, the Court, seven to two, in an opinion by Justice Amy Coney Barrett, upheld the act against the challenges to Congress’s power to enact it and to its requirements of state officials, and held that the challengers lacked standing to press their equal-protection and nondelegation claims.

Sovereignty as Survival

Kaysera Stops Pretty Places, who was Crow and Northern Cheyenne and lived with her grandmother, did not come home on the night of August 24, 2019. A young woman’s body was found in Hardin, Montana, on August 29, about two weeks after Kaysera’s eighteenth birthday; her family learned on September 11 that it was hers. Nagle, then a partner at Pipestem Law and the family’s lawyer, said that the body had been found about five miles off the reservation, which put the case under state jurisdiction, and that the FBI had declined to get involved.

For years the family urged the Big Horn County sheriff and county attorney to investigate. By March 2025 a person faced criminal endangerment charges in Big Horn County District Court in connection with her death, and Nagle, counsel to the family and to the National Indigenous Women’s Resource Center, said that “no family should have to beg law enforcement to investigate.”

Nagle now practices on her own from McLean, Virginia, and remains counsel to the National Indigenous Women’s Resource Center. “Protecting sovereignty is not a hobby,” she says. “For Native women and Native Nations, it is a matter of survival.”