FARGO, N.D. (AP) – A Spirit Lake Indian Reservation woman who was awarded custody of infant twin girls despite a history of child neglect was sentenced Wednesday to 30 years in prison in the death of one of the children, who was thrown down an embankment.

Hope Louise Tomahawk Whiteshield pleaded guilty in July to federal charges of child abuse and witness tampering in the June death of her step-granddaughter, who was just shy of 3 years old.

The case was one of several held up by U.S. authorities to show the ineffectiveness of the Spirit Lake tribe’s child protection system. The federal Bureau of Indian Affairs took over control of the tribe’s child social services more than a year ago.

An autopsy showed the girl died of a head injury. Authorities said that after the incident, Tomahawk Whiteshield bathed the unresponsive child, dressed her in pajamas and put her to bed. The 32-year-old woman then told other children in her household not to report what happened and went to sleep, prosecutors said.

U.S. District Judge Ralph Erickson said that while killing the child was “horrible beyond words,” the ensuing cover-up was the deciding factor in sentencing.

“The fact that no one sought help for this child is unfathomable,” Erickson said.

Assistant U.S Attorney Janice Morley said Tomahawk Whiteshield had been charged for child neglect offenses eight times in tribal court, including one case in which a 3-year-old was found wandering along a busy highway after Tomahawk Whiteshield forced the child to get out of her vehicle.

Jeanine Kersey-Russell, a foster parent who had custody of the twins for more than a year, said the tribe stepped in and said the girls would be better off staying with family. They were 26 months old when they were placed with Tomahawk Whiteshield, who lived in the town of St. Michael on the North Dakota reservation.

“We will live the rest of our lives wishing there was something we could have done to keep them safe,” she testified Wednesday.

Kersey-Russell said the surviving twin talks about her sister often and has a vivid memory of Tomahawk Whiteshield throwing the victim “down in the mud.”

Tomahawk Whiteshield declined to speak at the hearing. She wept as defense attorney Richard Henderson argued for a 25-year prison term, and the lawyer placed his hands on her shoulders.

Henderson said his client “knows she is responsible” for the child’s death and is “very, very sorry,” but that social services should never have left the twins in her care. There were five other children in the household.

Erickson said the tribal agency’s role wasn’t a subject for the sentencing hearing.

U.S. Attorney Timothy Purdon said the sentence was appropriate.

“Hopefully the stiff sentence imposed today will provide some measure of justice to her family,” Purdon said.

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