The emotionally charged case pits South Carolina law -- and the laws of most states, which consider the best interests of an adoptive child -- against the federal Indian Child Welfare Act.
The 1978 act was designed in part to protect the interests of Indian fathers when single mothers give up children for adoption. Private adoption agencies had been sending Indian children to white adoptive parents at a high rate.
"Veronica" was born in 2009 to a single Indian mother in Oklahoma. Her father, a Cherokee and a soldier at the U.S. Army's Fort Sill, Okla., texted the mother while she was pregnant, giving up all rights. But the father later decided he wanted the child, and eventually a divided South Carolina Supreme Court cited the federal act, said it trumped state law and ordered that the white adoptive parents, a James Island, S.C. couple -- the only parents the child knew -- would have to give up the 2-year-old.
She has since been living with her biological father.
At argument before the Supreme Court Tuesday, three justices seemed to favor the Indian father and three, including Chief Justice John Roberts, himself an adoptive father, inclined toward the adoptive parents, SCOTUSBLOG.com reported. Roberts questioned whether "one drop of blood" could entitle the father to protection under the federal act.
Veronica's court-appointed guardian ad litem told the high court in a brief the child's best interests lay with her adoptive parents.
The guardian said the "federal law ... implicates thousands of custody disputes every year."
"But under the South Carolina Supreme Court's interpretation of the act, the ... child's best interests were overridden by a federal law that in this case operated solely on the basis of race, not any meaningful connection to tribal sovereignty or lands," the guardian said.
A ruling should come before the end of June.
Duggar sisters unveil Christian dating rules in new book
Attkisson leaves CBS News, reportedly over network's 'liberal bias'