"Courts in seven states have held that ICWA does not bar courts from terminating the parental rights of a non-custodial father under state law when the father abandoned his child to the sole custody of a non-Indian mother," said Lisa Blatt, attorney for the couple.

She says the father's initial agreement to give up his parental rights meant he forfeited any subsequent efforts to establish custody, when the child was already in a happy, stable home environment.

The Capobiancos argue Brown had refused to offer any financial assistance to the biological mother until they were married and "wanted nothing to do" with the pregnancy.

As a single mother with two other young children, the biological mother felt she had no choice but to give her daughter up for adoption, said a legal brief filed by her lawyers. They say she complied with the adoption laws in both states and with the tribe.

The couple also says they long wanted to be parents and had seven unsuccessful attempts at in vitro fertilization. She is a child developmental psychologist and he is an automotive body technician. They were in the room when Veronica was born, and had an "open" adoption, meaning the biological mother could and did maintain a relationship with Veronica.

The case is Adoptive Couple v. Baby Girl, a Minor Child Under the Age of Fourteen Years (12-399).