Jodi Arias trial live video: Arias defense works to restore expert credibility

PHOENIX - The Jodi Arias murder trial was unexpectedly canceled Wednesday after a woman in the gallery vomited in court.

Before the disruption, Jodi Arias' defense team spent the day working to save the credibility of their expert witness.

Arias is accused of murdering her former boyfriend, Travis Alexander, in a jealous rage by stabbing him 27 times, slitting his throat and shooting him in the head.

If convicted, she faces the death penalty.

Psychologist Richard Samuels testified Arias’ lack of memory from the day she admits to killing Alexander is a combination of post-traumatic stress disorder, PTSD and dissociative amnesia.

Prosecutor Juan Martinez pointed out the multiple lies Arias told Samuels and eventually got Samuels to admit he should have re-administered at least one test.

Defense Attorney Jennifer Willmott started Wednesday’s testimony asking Samuels to point out the difference between the roles of therapist and evaluator.

Samuels said his role was to evaluate Arias and insisted his diagnosis is correct.

"The process of forming a diagnosis is not a simple process," testified Samuels.

Samuels also testified that Arias felt relieved after she finally admitted to killing Alexander.

The psychologist also told jurors Arias did not want all the sex.

“Well, for her, the relationship hadn't gone on for very long, and they were at some friend's house and, according to her story, he came into her room during the night and unclothed her and had oral sex with her,” Samuels said.

Samuels went on to explain the pressure he alleges Arias felt she had to go along with Alexander’s alleged sexual requests.

“At the time, her self-esteem was very low. The proceeding gap between his accomplishments and status in the community and hers was very great. She went along with it because she felt this was something he wanted. And in order to maintain the relationship with someone she respected, she went along with the oral sex,” Samuels explained to jurors.

When Arias began seeing Samuels, she was still claiming two masked intruders had killed Alexander. It wasn’t until 2010 that Arias changed her story for the third time and began claiming self-defense.

Willmott asked, "Did she think her life was in danger?"

"Yes," replied Samuels.

"Did she feel helpless?"  Willmott questioned.

“Yes," said Samuels.

Samuels then went on to explain his diagnosis would have been the same whether there were two masked intruders, or had Arias first told him she killed in self-defense.

Samuels will begin to answer jury questions when the trial resumes Thursday morning at 10:30 a.m.

Watch live trial coverage Mondays through Thursdays in the special coverage section of abc15.com.