Published: Mar 26, 2013 11:12 AM EDT

PHOENIX (AP) - A domestic violence expert is testifying in the trial of a woman accused of murdering her former boyfriend in his suburban Phoenix home.
    
The expert resumes testimony Tuesday after detailing her expertise to jurors on Monday.
    
A psychologist who diagnosed Arias with post-traumatic stress disorder and amnesia concluded nearly six days of testimony on Monday. The prosecutor questioned his credibility and accused him of forming a relationship with Arias that biased his diagnosis.
    
Psychologist Richard Samuels denied the accusations. He says he based his diagnosis on 35 years of experience and multiple tests.
    
Arias faces a possible death sentence if convicted of first-degree murder in the 2008 killing of Travis Alexander.
    
Authorities say she planned the attack on her lover. Arias first denied any involvement, then said it was self-defense.

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