Jodi Arias Trial: Prosecutor challenges psychologist who says accused killer has post-traumatic stress

(AP) PHOENIX - Jodi Arias lied repeatedly during her evaluation by a psychologist hired by the defense, who diagnosed her with amnesia and post-traumatic stress disorder, but most of the lies were irrelevant to his ultimate conclusions about her mental state, the psychologist testified Tuesday at Arias' murder trial.

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The prosecution at Arias' murder trial attacked the psychologist's credibility.

She 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 it then blamed it on masked intruders. Two years after her arrest, she said it was self-defense.

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Psychologist Richard Samuels took the witness stand for a third day Tuesday after testifying that he diagnosed Arias with PTSD and dissociative amnesia, which explains why she can't remember much from the day she killed Alexander. He said he met with Arias a dozen times for more than 30 hours over three years while she was jailed.

Prosecutor Juan Martinez then began seizing on multiple lies Arias told Samuels throughout the process of his evaluation, at one point getting the psychologist to acknowledge he should have re-administered at least one test he used to come to his PTSD diagnosis.

On Tuesday, Martinez again questioned Arias' repeated lies to Samuels, and asked how he could conduct a conclusive evaluation of the defendant without truthful answers.

"They can lie to about 10, 15, 20, 30, 50 things that you consider irrelevant ... and that still would not affect your opinion in this case, right?" Martinez asked.

"If there were 50, 60 points, yes, of course, it would raise alarm to me," Samuels replied, adding he did not consider most of the lies to be relevant to his diagnosis.

Martinez then read from a questionnaire Samuels had Arias fill out as part of his evaluation. He noted that at the time, Arias was still sticking to her story that intruders killed Alexander, and she noted that in the test.

"Granted, she told me one story and we found out later it was another story, but both could have been perceived as trauma," Samuels explained, again insisting the inconsistencies wouldn't alter his diagnosis. "It's not critical to the outcome of the test."

Martinez pounced, accusing Samuels of merely speculating that her lies wouldn't change a diagnosis.

"You don't know that do you?," Martinez asked loudly.

"No, I'm speculating," Samuels replied.

"Just made that up!" Martinez yelled, to which defense attorneys immediately objected.

A day earlier, Martinez also questioned Samuels' credibility, accusing him of blurring the line between objective observer and therapist when he bought Arias a self-help book about how to get over depression.

Samuels denied the accusation and said he remained objective throughout his time with Arias.

Arias spent 18 days on the witness stand 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.

She said she recalls little from the day of the attack.

Alexander suffered nearly 30 knife wounds, was shot in the head and had his throat slit before Arias dragged his body into his shower.

She said she recalls Alexander attacking her in a fury and said 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.

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 said she was too scared and ashamed to tell the truth.

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.

Complete coverage of Jodi Arias on Crimesider