PHOENIX (AP) -- Jodi Arias suffers from dissociative amnesia which explains why she can't remember much from the day she says she killed her lover in self-defense, a psychologist testified Monday at her Arizona murder trial.
Arias faces the death penalty if convicted of first-degree murder in the June 2008 death of Travis Alexander in his suburban Phoenix home. Authorities say she planned the attack in a jealous rage. Arias initially told authorities she had nothing to do with the killing then blamed it on masked intruders. Two years after her arrest, she said it was self-defense.
Arias spent 18 days on the witness stand over nearly six weeks during which she described her abusive childhood, cheating boyfriends, dead-end jobs, a shocking sexual relationship with Alexander, and her contention that he had grown physically abusive in the months leading to his death, once even choking her into unconsciousness.
She says she recalls little from the day of the attack.
"Amnesia is not necessarily a fake or made up kind of occurrence," psychologist Richard Samuels told jurors Monday. "It is not as if amnesia can only be made up to cover up something."
Samuels, a defense witness, is an Arizona-based expert whose website says he specializes in "sexually violent perpetrator evaluations, psychosexual risk assessments, sexual harassment and gender discrimination matters."
He said he met with Arias a dozen times for more than 30 hours over the past three years and that he eventually diagnosed her with PTSD and amnesia.
Alexander suffered nearly 30 knife wounds, was shot in the head and had his throat slit before Arias dragged his body into his shower.
Arias has said she recalls Alexander attacking her in a fury. She says she ran into his closet to retrieve a gun he kept on a shelf and fired in self-defense but has no memory of stabbing him repeatedly.
Arias' grandparents had reported a .25-caliber handgun stolen from their Northern California home about a week before Alexander's death - the same caliber used to shoot him - but Arias says she didn't take it. Authorities believe she brought it with her.
She has acknowledged trying to clean the scene of the killing, dumping the gun in the desert and leaving the victim a voicemail on his cellphone hours later in an attempt to avoid suspicion. She says she was too scared and ashamed to tell the truth, and that her memory from the day is full of gaps.
Samuels explained last week how when a person finds themselves in a stressful situation, the body releases hormones and adrenaline that block the brain's ability to retain memory.
"There would be a very severe trauma, some severe incident," Samuels said Monday. "It could be a killing. It could be a bomb going off."
While Samuels has testified about Arias' memory loss from the day of the killing, he has yet to offer an opinion on whether the killing appeared premeditated, as the prosecution contends.
The judge on Monday morning was prepared to hear arguments from attorneys before deciding if she would allow Samuels to offer his opinion, based on interviews with Arias and crime scene photos, on whether he believed the killing appeared planned. The prosecution had objected, and the defense inexplicably withdrew its motion and moved on with questioning about amnesia and memory loss.
Samuels went on to explain how traumatic events can cause "foggy or hazy" memories.
Arias has testified repeatedly that she was in a "fog" after she killed Alexander and has very few detailed memories from the day of the attack.
Since the trial began, none of Arias' allegations of Alexander's violence, that he owned a gun and had sexual desires for young boys has been corroborated by witnesses or evidence. She has acknowledged lying repeatedly but insists she is telling the truth now.
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