Collin County prosecutors are seeking to try a 14-year-old Wylie boy accused of killing a classmate as an adult.
The 14-year-old boy is accused of fatally shooting Nahum Martinez to death in March.
Closing arguments will begin Tuesday morning in the boy's certification hearing.
Police said the 14-year-old suspect hid evidence in the case, tried to hide Martinez's body and repeatedly lied to his family and investigators when asked about the slaying.
Several of the teenager's classmates testified Monday that the boy started bringing a silver handgun to school in the weeks prior to Martinez's shooting and showed it off to friends. The students said the boy kept the loaded gun wrapped in a T-shirt and inside a knapsack.
A psychologist who interviewed the 14-year-old testified that the boy does not have a major history of violence but admitted to having problems controlling his emotions. The psychologist said the boy said he had a troubled childhood. The psychologist testified that the boy said his father died when he was 7 years old, he has lived with numerous family members and has had issues with his mother.
The psychologist said the 14-year-old represented a "moderate risk for future dangerous acts" based on his past.
The boy's defense attorneys said prosecutors simply didn't met their burden of proof to have the 14-year-old face a murder charge as an adult.
Both sides will have a chance to tell their stories one last time to the judge before a ruling is handed down.