A former Mississippi Gulf Coast police officer has been sentenced to 20 years in prison for the death of her three-year-old daughter, who was left in a patrol car while her mother had sex with a supervisor.

Cassie Barker, 29, received the maximum sentence for manslaughter on Monday in Harrison County court after having pleaded guilty last month in the September 2016 death of her daughter Cheyenne Hyer.

Barker admitted to leaving Cheyenne strapped in a car seat in her patrol car for four hours while the mother was with her then-supervisor, Sgt Clark Ladner, at his home in Kiln after wrapping up a 12-hour shift just before 9am.

The car’s air conditioning was turned on, but it wasn’t blowing cold air. Outside the car, temperatures reached 100 degrees Fahrenheit that day.