RALEIGH, N.C. — Jurors learned about Matthew Grant's childhood Wednesday as defense attorneys presented their case in the trial of the man accused of shooting Wake County Deputy Mark Tucker.

Psychiatrist Dr. Seymour Hallek testified that Grant was physically and emotionally abused as he was moved from home to home as a young child.

"This youngster is exceedingly sad, anxious and depressed. His thinking at this time borders on psychosis, so he is not going to be the easiest child for any investigative team or therapist to work with," Hallek said.

Other doctors also suspected sexual abuse, but Hallek was not convinced.

"He constantly referred to himself as being bad. Apparently, he had been called that so many times before, he was used to it," Hallek said.

Hallek believed Grant's childhood impaired his decision-making ability on Feb. 12 when he shot and killed Tucker.

"When he is really under stress, he is overwhelmed and he cannot really scan his environment. He is likely to act impulsively and self-destructively," he said.

Defense attorneys are trying to prove that the crime was not pre-mediated, but impulsive, which would mean it would be considered second-degree murder.