Rockledge, Florida (Florida Today) -- The Florida man who left his infant daughter strapped into a car seat in a sweltering pickup truck was officially charged with third-degree felony murder, manslaughter and one felony count of leaving a child under the age of six unsupervised in a motor vehicle.
The formal charges against Steven Lillie were filed Friday by State's Attorney Phil Archer's office.
The charges indicate the state is ramping up its prosecution of Lillie, who was initially arrested and booked on charges of aggravated manslaughter, rather than murder.
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A conviction for third-degree murder carries with it a maximum sentence of 15 years and does not require the state to prove intent to harm, but it does require evidence that a death was caused during the commission of another felony, which in this case would be leaving a small child alone in a car for longer than 15 minutes.
When Lillie's 9-month-old infant, Anna Marie, died from heat stroke in June, the incident made national news. Lillie said it was an accident and that he had made a terrible mistake, and his case raised awareness of the danger of forgetting children in cars, especially in hot weather.
Lillie's daughter was the first of several American children to die this summer after being left alone in a car.