A decades-old cold case in Sioux Falls is no longer a mystery.
A woman is in the Minnehaha County Jail charged with the death of a baby boy found in a ditch 38 years ago.
The case begins in late February 1981.
Some people were test driving a car in the area of Sycamore and 33rd when they spotted blankets in the ditch.
Today, the neighborhood is full of houses.
But back then, it was a cornfield.
When officers arrived at the scene back in 1981, they found a newborn baby boy, dead, and wrapped in a blood-stained blanket.
“An autopsy revealed that the infant was born alive and had been breathing, but had slowly succumbed to exposure,” Sioux Falls Police Chief Matt Burns said.
Investigators followed up on leads, but they couldn’t find the boy’s family.
The case went cold.
That is until it caught the attention of Detective Michael Webb in 2009.
The baby’s body was exhumed at Saint Michael Cemetery so DNA samples could be tested.
No matches turned up in the DNA Database.
Recently, the department turned to genealogy services.
“What’s coming across the news in the last year, we learned that DNA coupled with genealogy is solving a lot of major cases across this country, including last summer’s with the Golden State killer,” Sioux Falls Police Detective Michael Webb said.
That eventually led police to 57-year-old Theresa Bentaas of Sioux Falls.
Police say she’s the mother of Baby Andrew John Doe.
According to court papers, Bentaas admitted to hiding the pregnancy from family and friends; giving birth to the child in her apartment alone; then driving the baby to the place where he died.
She called herself “young and stupid.”
When she drove away from the ditch on that day in 1981, she told investigators she was “sad, scared, and ran away from it and was not smart.”
When investigators asked if she thinks about it when she drives by the area today she said “of course.”
After nearly 40 years, Webb said Baby Andrew’s voice has been heard.
“I know it sounds cliche, but we don’t quit on these. And I’ll be the first to admit, you work pretty hard when it’s a child case. You go through a lot of frustrations and you get knocked down a lot and you keep getting back up and you don’t quit and that’s what we did,” Webb said.
Bentaas is charged with alternative counts of murder and manslaughter.
The father was not charged. Detective Webb said he did not know.
Court papers do say he noticed Bentaas “had a bump and then no bump” around the time the victim was found.
But he didn’t believe she was capable of doing such a thing.