03/22/2013 02:56 pm ET

Jodi Arias Trial: Psychologist Richard Samuels Hammered For Changing PTSD Test Score

Jodi Arias' murder trial turned nasty Thursday as an Arizona prosecutor launched a bare-knuckle attack on a defense expert who claims Arias suffers from post-traumatic stress disorder.

"Isn't it true that ... you have compassion for the defendant ... Isn't it true that you have changed or done things ... because you have sympathy or bias toward the defendant?" Maricopa County Prosecutor Juan Martinez asked psychologist Richard Samuels on redirect.

"Absolutely not," Samuels replied.

Arias, 32, is accused of the June 4, 2008 slaying of her ex-boyfriend Travis Alexander, inside his Mesa, Ariz., home. The prosecution contends Arias stabbed 30-year-old Alexander 27 times, shot him twice in the face and slashed his throat in a jealous rage. Arias told jurors she killed Alexander in self-defense during an argument over a dropped camera that followed his escalating sexual demands.

Samuels said all the information he gathered on Arias, including her test results, support a diagnosis of PTSD. Samuels also said the condition likely explains why Arias has holes in her memory of the night she killed Alexander -- gaps exposed repeatedly by Martinez during an aggressive cross-examination of Arias.

Martinez walked the jury through perceived inconsistencies in Samuels' test methods, bringing up two score sheets from Arias' post-traumatic stress diagnostic test.

The score sheets indicate Samuels scored the same test twice and each sheet contains different results.

Martinez accused Samuels of changing the test results to give Arias a higher score on the test.

"Sir, that's a change, yes or no?" asked Martinez, pointing out that one score sheet, filed before the start of the trial, indicated Arias had a symptom severity score of 33, while the other score sheet -– provided to Martinez after the trial began -- gave her a score of 35. The latter of the two also had a handwritten note next to the score that stated the results supported a "moderate to severe" diagnosis.

"I scored it twice," Samuels replied.

"That's a change right?" Martinez asked.

"That's a change," Samuels said.

With the test scores as the main weapon in his arsenal Thursday, Martinez attacked Samuels' character and tried to accentuate the psychologist's supposed misconduct, which Samuels vehemently denied.

"The first copy was sent in as part of my evaluation. But I didn't have access to it, so I recalculated it again so that I would have something to review when I was going through my reports," Samuels said.

He calculated the scores twice because he misplaced the original test. When he scored it a second time, Samuels found it was higher, he said. He contended that regardless of the two differing scores, both meet the criteria for a diagnosis of post-traumatic stress disorder.

"It did not change the utility of the test," Samuels said.

His memory was another target for the veteran prosecutor. "Do you remember saying it's not something you were concerned with ... because she would have scored higher anyway?" Martinez asked.

"I don't remember," Samuels said.

"Do you have problems with your memory then?" asked Martinez.

"No, sir, no more problems than you do," Samuels replied.

"Sir, with regard to this issue, have you conducted a diagnostic test on the prosecutor?" asked Martinez.

"No, I have not," said Samuels.

"How would you know about his memory problems?" asked Martinez snapped, resulting in an immediate objection from the defense.

On Thursday, Samuels was grilled by the jury about his PTSD diagnosis of Arias. Arizona is one of three states that allow jurors to pose questions to witnesses after prosecution and defense lawyers have finished their questioning. Arias' defense attorney, Jennifer Willmott, wrapped up her redirect examination of Samuels Wednesday, giving the 12 jurors and six alternates -- seven women and 11 men –- their first opportunity to put questions to the defendant.

"Do you feel comfortable with diagnosing a person with a condition if they continually lie to you, hypothetically speaking?" a juror asked.

"Well if I knew someone was lying and what they were telling me was unsubstantiated by anything else and somehow I knew they were lying, I would not make a diagnosis. That would be inappropriate," said Samuels.

Another juror asked, "Can you be certain that Arias is telling you the truth about the day Alexander died?"

Samuels replied, "Not with 100 percent certainty. I can't say that."

"It is important to note that the diagnosis of post-traumatic stress disorder is not a 'get out of jail free' diagnosis, it is simply a statement that describes her emotional state at the time the evaluation occurred."

The trial is scheduled to resume at 1 p.m. Eastern time Monday, when Martinez will continue his redirect of Samuels.



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