Anderson Cooper 360

Tonight on AC360: Parents appeal to U.S. Supreme Court for baby Veronica

3-year-old Veronica may be too young to realize she's at the center of a contentious legal battle between her biological father and the parents who thought they had adopted her. She was taken from Matt and Melanie Capobianco's home on New Year's Eve 2011 after they had raised her for two years.

Since then they've been fighting a South Carolina court's decision. They appealed to the South Carolina Supreme Court, but the justices upheld the ruling. Now, they're petitioning the United States Supreme Court to overturn the verdict.

The couple had arranged to adopt Veronica from her birth mother before the child was born. They were told the father, Dusten Brown, waived his parental rights and he signed a document saying he would not challenge the adoption.

In a surprising turn of events, when Veronica was 4 months old, her father filed for paternity and custody citing a federal law from 1978 called the Indian Child Welfare Act.

Brown's lawyers say Veronica is "happy, healthy and thriving." But the Capobiancos argue the law intended to protect children with Indian ancestry was misused in their case because Veronica was never removed from an Indian home, but was with them from the start of her life. Others argue federal law shouldn't override state law.

Will the U.S. Supreme Court take the case? Who should have custody? What's the legal precedent? At 8 and 10 p.m. ET we'll get expert legal insight from Jeffrey Toobin, and hear from the Capobiancos.