In a few short weeks, Jodi Arias has become the most talked-about criminal defendant since Casey Anthony.
The 32-year-old photographer is fighting for her life in an Arizona courtroom, where she faces charges of stabbing her ex-boyfriend, shooting him in the face, and slitting his throat four years ago.
Since the investigation began, she's changed her alibi -- and her lawyers -- several times. In early January, the prosecution began presenting damning evidence, including photos that they contend tie Arias to the grisly murder scene and recorded interviews in which she says one puzzling thing after the next.
The ultimate challenge for those who are watching the trial -- and for the jurors who will decide the case -- is how to make sense of the contradictions in her statements and of Arias herself.
"People aren't really talking about her demeanor and how it fits a particular personality profile," Dr. Scott Bonn, a crime expert and assistant professor of sociology at Drew University told The Huffington Post.
"She is really a walking embodiment of sociopathy in many ways," Bonn continued. "The ironic thing about that, I believe, is that is part of the intrigue. There's a disconnect: How can this pretty young woman be responsible for this reprehensible, incomprehensible act?"
Arias is accused of butchering Travis Alexander, her ex-boyfriend, on June 4, 2008 while he was in the shower of his Mesa, Ariz., apartment. He was found dead days later on June 9. When questioned by police, Alexander's friends and family members indicated that Arias should be questioned.
Bonn has not interviewed Arias and can only speculate on the reasons for her behavior based on her actions, media appearances and police interviews -- of which there is no shortage.
Arias, according to testimony in court, was jealous of Alexander seeing other women and allegedly slashed the tires on his vehicle twice. After those incidents, his new girlfriend received a harassing email from a "John Doe." Alexander suspected that Arias was responsible, and told friends that he suspected Arias had hacked into his Facebook account.
Based on his observations of the police interviews and evidence presented at trial, Bonn said it is his opinion that Arias was "completely obsessed" with Alexander.
"In her own twisted way, she was infatuated and in love with him," he said.
"[Arias] was totally obsessed with him," Alexander’s close friend Sky Hughes told The Huffington Post. "She wouldn't let him go. Whenever he would try to sever all ties, she would threaten to kill herself ... He would tell her he didn't want anything to do with her, and she would show up at his house. We knew it was her. We didn't want it to be her, but [we] just knew it was."
Like Bonn, Sheila Wendler, a forensic psychiatrist with the Hawaii Department of Public Safety, Corrections Division, has not personally examined Arias but can speak in general terms regarding similar cases.
Wendler said it is not uncommon in cases such as this for the perpetrator to have characteristics of borderline personality disorder.
"[This would include] unstable interpersonal relationships and intense fear of abandonment or rejection by their partner," Wendler said. "They may react in extreme ways to avoid abandonment, including becoming suicidal, self-mutilate or react with intense anger, which they may have difficulty to control. These women can become cruelly punitive toward whom they perceive as rejecting them."
Wendler added, "Their mood is usually unstable and may vary from happiness to anger to euphoria or to despair all in the same day."
When police initially questioned Arias, she said she last saw Alexander in April 2008.
"I would never want to hurt him ... if I was going to ever try to kill somebody, I would use gloves. I have plenty of them ... I did not take his life," Arias told a police detective in a July 15, 2008, taped interview that was played at her murder trial.
When police later discovered hair and a bloody print found inside Alexander's home that belonged to Arias, she changed her story and admitted she had been present when Alexander was killed but said she was not responsible. She said two unidentified intruders had murdered him and she managed to escape.
"I'm not the brightest person, but I don't think I could stab him, I'd have to shoot him ... The least I could do is make it as humane as possible," Arias told police.
The stories she told police are contradicting and inconsistent, and yet she told each one with "unabashed, cold and calculating clarity," Bonn said.
In Sept. 2008, Arias gave a jailhouse interview to the Arizona Republic. She again denied killing Alexander.
"God knows I'm innocent. I know I'm innocent," said Arias. "I had nothing to do with his murder. I would never hurt him. He was my friend."
That same month Arias was again on TV, telling the TV show "Inside Edition" the story she had told police about the two intruders.
"No jury is going to convict me ... because I'm innocent, and you can mark my words on that one: No jury will convict me," Arias told "Inside Edition."
In August 2011, HuffPost obtained court documents that indicated that Arias had changed her story yet again -- this time claiming self-defense. In the most recent version, Arias, according to the documents, claimed she was a victim of "sexual and physical abuse" by Alexander and killed him in self-defense.
"This self-defense position that she is taking is the third in a series of realities that she's created, none of which is consistent with the other," Bonn said. "It's consistent with a sociopath personality. She's so narcissistic and enamored with herself that she thinks she can make it believable."
In addition to borderline personality disorder, women like Arias often meet the criteria for both sociopathy or psychopathy, according to Wendler.
"The characteristics of psychopathy include disregard and violation of other people's feelings, wishes and rights," Wendler told HuffPost. "These individuals use deceitfulness and manipulation to obtain what they want (pleasure, profit, etc.). They are often called pathological liars. They are self-centered and show reckless disregard for the safety of others; they lack empathy towards their victims and have little or no remorse about their criminal actions."
Arias' trial began on Jan. 2 of this year, and prosecutors rested their case on Jan. 17. Arias' lawyers will begin to present their case on Jan. 29. According to Bonn, she will likely need to take the stand if she wants to convince the jury that she killed Alexander in self-defense.
"The only way it's going to have any veracity with the jury is if she takes the witness stand. I think she has to -- absolutely has to -- in order for it to play for the jury. And if she comes off as the battered woman, then maybe she has a shot," Bonn said.
JODI ARIAS' PERSONAL PHOTOS: (Article Continues Below)
The alleged premeditation in the case, however, will be hard to disprove. Prosecutors have painted a picture for the jury in which Arias stole a handgun, rented a car at considerable distance from her home and drove to Alexander's apartment with the intent to kill him and afterward crafted an elaborate alibi.
Bonn acknowledged the apparently premeditative aspects of the crime, but said that in his opinion, things could have gone one way or another, assuming Arias killed Alexander in 2008.
"I think she went there prepared to kill and what probably happened -- and would be consistent with a sociopathic emotional outburst -- is he might have shoved it in her face about going with another women or something along those lines that triggered her jealously and she snapped. I think that's a very likely scenario," Bonn said.
And Bonn suggested the self-defense theory might not be too far-fetched -- at least to Arias' way of thinking.
"In her mind, she felt like the jilted woman," he said. "It's narcissism, [to] always see things from her perspective, her needs and her desires. In her mind, this really may be self-defense because she believes she was wronged -- 'How dare he be with another woman when he is hers?' Sociopaths create a reality that fits the event."
Bonn added, "The rage and retribution demonstrated by the brutal slaying of Travis is very consistent with the emotional volatility of a sociopath. In her narcissistic mind, Travis deserved to die for betraying her."
Wendler agreed with Bonn, saying individuals like Arias will blame the victim for "deserving their fate."
"These individuals may have a grandiose view of themselves and be arrogant," she said.
Arias' trial is expected to last until mid-April. If convicted, she could face the death penalty.