(PHOENIX) -- The psychologist called by Jodi Arias' defense team has admitted that the accused murderer lied to him during a post traumatic stress disorder test, and told the court that the test should have been re-administered.
Dr. Richard Samuels told an Arizona court Monday that he diagnosed Arias, 32, with PTSD after she shot and repeatedly stabbed her ex-boyfriend Travis Alexander in the summer of 2008. But Samuels also admitted Arias lied to him at the time he gave her the PTSD test, telling him what she told authorities during her police interrogation -- that two masked intruders killed Alexander as she cowered in the corner. She later admitted she killed Alexander, but claims it was in self defense.
When pressed by prosecutor Juan Martinez, who said that a PTSD test is really only as good as the person filling it out, Samuels admitted his possible error.
"Perhaps I should have re-administered that test," Samuels said.
Samuels testified that as a result of the stress of killing Alexander, Arias developed amnesia and can't remember stabbing and shooting him. Arias has said repeatedly that she has "no memory of stabbing [Alexander]."
Alexander was stabbed more than two dozen times, had his throat slit and was shot in the head before his body was dragged into the shower in his Mesa, Ariz., home. Arias had been charged with first-degree murder and could face the death penalty if convicted.
"People who are involved in imposing harm to another can develop PTSD as a result of the harm they have caused," Samuels said.
Samuels said that he can explain all of Arias' lies in the days after the crime, like leaving a voicemail for the man she just killed. He told the jury she was creating an "alternative reality" to escape the horror of what she did.
"By creating her alternative reality, it's as if it didn't happen, and it reduces the level of stress," he said.
On cross examination, Martinez portrayed Samuels as gullible and at one point, the prosecutor told Samuels that there is an appearance that he is trying to help Arias.
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