Transcript for Arias Prosecutor: 'She Knew She Was Going to Kill Him'
But first the very latest on the jodi arias trial. The closing arguments by her defense team start today and thursday, prosecutor juan martinez called arias a manipulative liar who won't let travis alexander rest in peace. Abc's ryan owens has more from the courtroom in phoenix. She knew. She absolutely knew and had already planned it. She knew she was going to kill him. Reporter: Prosecutor juan martinez believes jodi arias should die for killing her exnd and he went for her jugular during closing arguments. She may cry now, but the jury instructions have told you that sympathy is not to be considered in this particular case. No doubt that she did it. Reporter: He called the 32-year-old a master manipulate ir. A chameleon. Absolutely without a shadow of a doubt she's a liar. Reporter: He said her lying didn't stop when she pledged to tell the whole truth and took the witness stand for those 18 long days. It's like a field of lies that has sprouted around her as she sat on that witness stand. It's every time she spat something out, another lie, another weed would grow around her. Reporter: Arias admits she repeatedly stabbed and shot travis alexander but testified it was in self-defense, that alexander abused her. Everything in this case points to the fact that it did not happen. There are no medical reports. Reporter: Martinez reminded the jury of the brutality of the killing in june of 2008 by showing bloody crime scene photos and autopsy pictures of alexander's many wounds. His family and friends filled up three rows of the courtroom and shielded their eyes. And as he sits there, doesn't have any dignity either. She's taken that away from him. Reporter: The usually animated prosecutor notorious for yelling at witnesses whispered as he described the attack. Sitting there, not only is he defenseless, he does not have a gun, he does not have a knife. Reporter: Later today arias' defense team will get their chance to deliver closing arguments to the jury hoping to convince at least one of the jurors jodi arias is a battered woman who doesn't deserve to die for what she did. For "good morning america," ryan owens, abc news, phoenix. And for more now let's turn to "gma's" legal analyst dan abra this was a victory for the defense to get the option of first degree, second degree murder or manslaughter, wasn't it? There's. If any of the jurors are inclined to compromise, manslaughter offers that opportunity. Remember, if the jurors believe jodi arias' story even a little bit. That he lunged at her. That he lunged at her and then, let's say she didn't legally defend herself, she overreacted, shouldn't have killed him but if the jurors believe that account, that could be manslaughter. I mean he comes after her, she vastly overreacts and kills him, that could be considered manslaughter instead of murder. I don't think that's how the jury will end up finding this case but it's a win for the defense. You never know and to have the third option is a win for the defense. You have not been a fan sometimes of want martinez. How do you think he did? I think he did a good job. A lot of what I found over3w50rd was effective here. I walked away from juan martinez's closing argument exactly as he would have hoped thinking to myself, wow. Jodi arias has a terrible case here. Well, the whole she won't let him rest in peace. She didn't just kill him, she's trying to kill his character by saying he was an abuser, into child pornography. Three key issues he focused on premeditation, went through the crime moment by moment and focused on her lies and I think those three things were effective. Dan abrams, thanks so much.
This transcript has been automatically generated and may not be 100% accurate.