DEDHAM, Mass. (AP) – A traffic stop turns into a high-speed chase, and when it is over, police make a horrific discovery inside a stolen SUV: the body of a 6-year-old girl, naked and wrapped in a comforter, is wedged on the backseat floor.

Two years later, the girl’s 22-year-old cousin, Ryan Bois, is set to go on trial in her killing. Jury selection begins Monday in Norfolk Superior Court in Dedham.

Prosecutors say Bois kidnapped Joanna Mullin in the middle of the night during a sleepover at her grandmother’s house in Weymouth, then raped and strangled her.

Bois allegedly climbed on top of his grandmother’s Ford Explorer and cut open a screen to get into the house.

Police attempted to pull Bois over when they spotted him driving erratically in Weymouth at about 1:30 a.m. on Aug. 5, 2007. He allegedly sped away, crashed his car into a taxi in Quincy, then fled on foot. When police caught him, he allegedly said, “Kill me. I’m a loser – you don’t even know. Shoot me in the face.”

Bois has pleaded not guilty to 13 charges, including rape, murder, home invasion, kidnapping, assault with a dangerous weapon, drug possession and multiple motor vehicle charges.

Police said he had heroin on him when he was arrested and threatened a police officer with a knife.

Bois’ lawyer, Beverly Cannone, did not return calls seeking comment Friday. During a pretrial hearing last week, she said she may use an insanity defense.

Joanna’s family did not want to comment before the trial, said her uncle, James Mullin, a Weymouth police captain.

Joanna had attended kindergarten at the Pingree School in East Weymouth and was about to start first grade when she was killed.

Bois had an outstanding warrant for violating his probation on robbery charges at the time of his arrest.