By Joseph A. Slobodzian and Melissa Dribben The West Philadelphia teen charged with killing Philadelphia Police Officer Isabel Nazario at the end of a high-speed chase and collision in 2008 pleaded guilty this morning in an agreement that will put him in prison for 10 to 20 years.

Andre Butler's plea was announced this morning by Assistant District Attorney John Doyle on what was supposed to have been the first day of jury selection in his trial in the death of Nazario, 40, an 18-year veteran of the police force.

Butler, 18, of Mantua, pleaded guilty to third-degree murder, aggravated assault and related charges before Common Pleas Court Judge Jeffrey P. Minehart.

Butler was arrested Sept. 5, 2008 after he fled the scene of the accident in which his stolen Cadillac Escalade plowed into the car in which Nazario was a passenger.

Nazario was killed instantly. Nazario's partner, Terry Tull, 39, a 14-year officer, was seriously injured but has returned to active duty.

Before Minehart imposed sentence, Nazario's daughter Jazmine, the officer's sister and a niece as well as Tull gave victim impact statements.

Jazmine, who was 15 when her mother died and is 17 now, said she should not have to reread the cards and letters her mother wrote to her to remember her mother.

"For the rest of my life, I'll never see my mother's beautiful smile, hear her voice, or be happy with her," she said.

Tull, his voice rising in anger, said to Butler: "You were 16. You should have been playing a video game . . . instead of causing the destruction of my life and their lives" referring to Nazario's family.

"Can you give me one good reason why?"

Contact Joseph A. Slobodzian at 215-854-2985 or jslobodzian@phillynews.com.