(PHOENIX) -- Accused murderer Jodi Arias was confronted Monday with a barrage of lies she told after she killed her ex-boyfriend Travis Alexander, but she twice defiantly declared that she was innocent of first-degree murder.
"It's the truth. I'm innocent of that charge," Arias said to prosecutor Juan Martinez, referring to the criminal charge that could carry the threat of the death sentence if she is found guilty.
Arias admitted on the stand that she lied for months and years after killing her ex-boyfriend, telling investigators and friends that she had nothing to do with Alexander's grisly death, in which he was stabbed 27 times, his throat was slashed, and he was shot in the head.
Eventually, Arias confessed to the killing, but claims it was in self-defense.
On Monday, prosecutors hammered Arias about her lying, getting her to admit to lies she told and playing video of her police interrogation and a TV interview in which she told stories that she has since conceded were not true.
In an interview with CBS' 48 Hours, Arias said she smiled for her mug shot partly because she knew she was innocent.
"You truly believe that you didn't do anything wrong here?" the prosecutor asked incredulously.
"I believed that I knew that I was not guilty of first-degree murder and I did plan to be dead," she replied, a reference to her claim that she planned to commit suicide.
During a day of contentious questions and answers between Martinez and Arias, the prosecutor used Arias' own diary entries and text messages to show contradictions of her claims that Alexander was abusive toward her, that he hit her and tried to choke her.
Arias said that in early 2008, Alexander hit her in the neck while they were riding in his car. Martinez showed a diary entry describing the day they rode in the car, and there was no mention of physical violence.
"This entry does not corroborate what you told us happened in the car," he said. "With regard to the [choking incident] you didn't call police. You didn't tell anyone about it. There is no corroboration anywhere in your journal. All we have is your word. Are there photos? Any other writings? Is there a police report? Is there a medical report?"
Arias said there was no evidence that the alleged abuse happened, except for her testimony in court.
"There's no evidence because it didn't happen, did it ma'am?" Martinez yelled.
Arias said that she had told one person about the abuse she claims she suffered at the hands of Alexander, and that it was another ex-boyfriend, Matthew McCartney. But when pressed for details about the conversation in which she told him, Arias became confused and changed her answers.
"I saw [Matt] a few days later, and he called me out on the bruises," Arias testified.
"Over the phone, just days after I think," she said.
"Isn't it true he wouldn't have been able to see your injuries because you were talking over the telephone?"
"No, I was in Yreka [California] by then. I stopped to see Matt after I left Arizona. Let's see, I believe it was two or three days after. I'm not saying there was no telephone call, [but] it was at his house. I went and saw Matt, and some makeup wore off, and he confronted me on [the bruises]."
Martinez said that McCartney has denied the conversation ever took place.
The argument mounted by Martinez Monday echoed the focus of the prosecution throughout the trial: that Arias murdered Alexander and then lied to everyone about it to evade arrest and prosecution.
"Ma'am you have a problem with telling the truth don't you?" Martinez asked as his first question Monday, the 11th day Arias has been on the stand explaining her role in Alexander's death.
"Not typically," Arias responded.
Martinez pointed out that Arias lied to Detective Esteban Flores of the Mesa, Ariz., police department as he investigated Alexander's death. She initially denied to the detective that she was at Alexander's home in Mesa when he was killed, and later said he was murdered by a pair of masked intruders.
Arias argued with Martinez, claiming that she lied to investigators out of shame, and lied to friends immediately after the death out of confusion.
"My mind wasn't right during all that period," Arias said referring to the hours immediately following the killing when she drove through the Arizona desert and made phone calls to McCartney and new love interest Ryan Burns.
"It's like I wasn't accepting it in my mind...because I never killed anyone before," she said.
Martinez also suggested that Arias tried to find out the status of the investigation into Alexander's death so that she could know if she were about to be arrested. When a friend of Alexander's called her to report the news about Alexander's death, Arias asked about details into the investigation, the prosecutor said. She also called Alexander's Mormon bishop and asked him what he knew about the case, and then asked friends and family members what they knew, according to Martinez.
He also went over lies that Arias told to her friend, Leslie Udy, and Ryan Burns, both of whom she saw in Utah the day after killing Alexander. She talked to both about Alexander as if he were still alive. Martinez pointed out that Arias even made out with Burns in his bedroom during their visit.
But Arias claimed that it was Burns who lied about their encounter.
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