A Stanislaus County jury’s decision on the issue of sanity for a man convicted of stabbing a 25-year-old Turlock man to death may come down to what doctor they give more credence.

Nicholas Harris was previously convicted of second-degree murder for the death of Mark Henson on Aug. 12, 2008. He was also found guilty of arson and an enhancement of using a deadly weapon. Henson was stabbed repeatedly before he was able to break away from Harris and run for help. He died on a neighbor’s front porch. Harris also set Henson’s car on fire after Henson ran.

Harris has entered a not guilty by reason of insanity plea and now the same jury that convicted him must determine if he was insane when he killed Henson, who he believed was harassing his girlfriend.

To prove insanity, the defense has to first convince the jury the defendant had a mental disease, defect or disorder. Then they have to prove that more likely than not the mental disorder rendered the defendant incapable of understanding the nature of his actions and that they were morally and legally wrong.

Two court-appointed psychologists testifying for the prosecution stated they do not believe Harris had any mental disorder that prevented him from grasping the moral and legal ramifications from his actions during the offense. A third psychologist called by the defense testified he believes Harris is bipolar.

Defense attorney Steven O’Connor told the jury that Harris had been undergoing an “accelerated unraveling” since 2006 and that it wasn’t until after his arrest that he was diagnosed as bi-polar and given medication to control his symptoms.

Harris’ parents previously testified that their son had a history of depression, obsessive compulsive disorder and attention deficit disorder. They both stated he had been displaying increasingly odd behavior leading up to the attack. His father testified that his son told him the neighbor’s gardeners were out to kill him. The statements were made hours after the fatal attack and prior to the family learning of Harris’ involvement in Henson’s death.

On Wednesday, psychologist Phil Trompetter testified that in his opinion Harris showed all the signs and symptoms of having bipolar one. This included pressured speech, hyperactivity, and mood swings.

Bipolar is a mental disorder marked by mood swings of mania and depression. With bipolar one a person may be in a manic state or a mixed state of mania and depression for at least seven days and a depressive state for about two weeks, according to the National Institute of Mental Health.

The defense claims Harris was in a manic or mixed state during the offense and the subsequent video confession with police investigators.

On Thursday the prosecution sought to refute Trompetter’s opinion by calling psychologists Phillip Hamm and Jocelyn Roland to the stand. Both psychologists testified they did not believe Harris is a bipolar.

Hamm testified that he met with Harris for about two hours and that after the interview and reviewing his records, he determined Harris had “some personality traits” but not a personality disorder.

“He was not suffering from any disease, defect, or disorder that would have rendered him incapable of understanding his conduct or recognizing it was wrong,” Hamm said. “He had no mental disorder that would rise to the level of insanity.”

Roland also testified that after gathering Harris’ history and interviewing him for three hours, she found no evidence that he had a mental disorder.

The sanity phase of the trial will resume today in Stanislaus County Superior Court.