Cassie Barker admitted she left her 3-year-old in a hot car while she had sex with her supervisor inside his house.
It was a searing 100 degrees farenheit when Cassie Barker finished her shift as an officer for the Long Beach Police Department on the Mississippi Gulf Coast in September 2016.
Barker, then 27, headed over to the Kiln home of her then-supervisor, Sgt. Clark Ladner, with her daughter, Cheyenne Hyer, in her patrol car.
She told authorities at the time she was “visiting” with Ladner, then 36, when she left 3-year-old Cheyenne strapped in her car seat in the back of her patrol car to go see him, local station WXXV 25 reports.
She later admitted that while Cheyenne sat in the back seat, she and Ladner had sex, CBS News reports.
She stayed inside Ladner’s house for more than four hours, telling authorities she fell asleep.
Ladner said he took a sleeping pill and had no idea that Hyer’s daughter was in the car in the sweltering heat, say authorities.
But Cheyenne was in the car, dying because of the sweltering heat, while her mother was inside Ladner’s house, prosecutors say.
Barker said she had left the car running and the air conditioning on, but authorities said it wasn’t blowing cold air.
When Barker returned to the patrol car, she found her daughter unresponsive.
The child was rushed to a nearby hospital where her body temperature was 107 degrees farenehit, CBS News reports. She was pronounced dead at the hospital.
Barker, now 29, faces up to 20 years in prison after pleading guilty Monday to culpable negligence manslaughter for leaving her daughter to die in her patrol car.
She had originally been indicted on a second-degree murder charge, the Biloxi Sun Herald reports, but she pleaded guilty to the lesser charge as part of an agreement with prosecutors.
During their investigation, detectives allegedly learned that this wasn’t the first time Barker had left her daughter alone in a car after allegedly doing so in April 2015 when she ran into a store in Gulfport, CBS affiliate WLOX reports.
After a passerby called police, child welfare officials took temporary custody of Cheyenne. Barker was suspended from the Long Beach police for a week without pay.
The girl’s father, Ryan Hyer, said he was never notified of that first incident, WLOX reports.
Prosecutors are recommending 20 years in prison when Barker is sentenced on April 1.
“I don’t know what I could ever do to you that could be worse than what you’ve already experienced,” Harrison County Circuit Judge Larry Bourgeois told her in court, WLOX reported. “You will forever be entombed in a prison of your own mind.”
An attorney for Barker did not immediately return PEOPLE’s request for comment.
This first appeared on PEOPLE.