Jodi Arias's Final Expert Witness Claims PTSD
PHOTO: Defendant Jodi Arias talks with her attorney during her trial at Maricopa County Superior Court in Phoenix, April 25, 2013.

In a last-ditch effort to avoid conviction and save the life of accused murderer Jodi Arias, her defense team today called a final expert witness they hoped would convince jurors that Arias suffered post-traumatic stress disorder that caused her to kill her boyfriend.

"We're looking at a consistent pattern of trauma," psychologist Robert Geffner told the jury on what is expected to be the last day of testimony.

Arias' attorneys have argued that she was abused, both physically and emotionally, by ex-boyfriend Travis Alexander in the months leading up to his death.

She has confessed to killing Alexander during a violent argument on June 4, 2008, claiming that she accidentally shot him in self-defense when he charged at her in a rage after having sex and taking nude photos of each other.

Prosecutors argue that she drove to Alexander's house with intent to kill, and then stabbed him, shot him, and slashed his throat before leaving him to die. Expert psychologists who testified for the prosecution have said Arias showed signs of borderline personality disorder, not PTSD.

The difference could be significant for a jury. PTSD would suggest that Arias had experienced traumatic abuse. The prosecution's expert said symptoms of borderline personality disorder includes a history of unstable personal relationships, inappropriate anger, feelings of emptiness, suicidal thoughts and some elements of paranoia.

Arias, 32, is charged with first-degree murder and could face the death penalty if convicted.

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Today's testimony by Geffner was squeezed into the trial's schedule at the last moment to give the defense an opportunity to counter the prosecution's borderline personality claim.

"She could be suffering from PTSD and borderline personality disorder, but if all of your symptoms of borderline came after the event, it's not appropriate to call it just borderline," Geffner said. "All your tests are supporting some sort of anxiety disorder."

Geffner went over the results from four diagnostic tests taken by Arias in the years since she was arrested in July 2008. He said that all the tests indicated that she answered the questions honestly, without lying. Prosecutors have tried to paint Arias as a serial liar throughout the trial.

Geffner said that Arias' test answers all pointed toward anxiety stemming from trauma.

"The tests would indicate significant trauma, and significant issues that cause symptoms with the way this person views themselves, the way they experience themselves, which could be present in an anxiety disorder or post-traumatic stress disorder," Geffner said.

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Following Geffner's testimony, the prosecution will have one last opportunity to present their own expert to rebut Geffner's claims.

The trial, which began in January, is expected to wrap up this week, with closing statements on Thursday and Friday.

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"Jurors after a while, if they start to feel preached to, if they start to feel like we've already heard an expert talk about this, they begin to get resentful," clinical forensic psychologist Dr. David Bernstein told ABC News.

The jury is expected to begin deliberations on Monday. ABC News' Shana Druckerman contributed to this report.

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