The jury reported its impasse to the judge after only about two and a half hours of deliberations that began Tuesday afternoon.
"I do not wish or intend to force a verdict," Judge Sherry Stephens told jurors before sending them back to continue deliberating.
The panel heard emotional comments last week from the family of victim Travis Alexander as the prosecutor argued that the 32-year-old Arias should be executed for the gruesome killing.
Arias responded Tuesday by pleading for mercy, saying she can become a model prisoner who teaches inmates how to reach and speak Spanish, helps the prison launch recycling programs. She also wants to be an advocate for domestic violence victims.
The same jury of eight men and four women convicted jury of first-degree murder two weeks ago in the death of Alexander, who was stabbed nearly 30 times and nearly decapitated in what authorities said was a jealous rage.
Tuesday night, Arias spoke to spoke to The Associated Press and other media outlets in jailhouse interviews just hours after the jury began deliberating her fate. She spoke out about her murder trial, her many fights with her legal team and her belief that she "deserves a second chance at freedom someday."
She said her lawyers let her down by not calling more witnesses who could have bolstered her claims that she was a victim of domestic violence at the hands of Travis Alexander.
Arias was convicted last week of first-degree murder in the June 2008 stabbing and shooting death of her one-time lover in what prosecutors described as a cold, calculated killing carried out in a jealous rage. Arias maintains it was self-defense.
The jury began deliberating Tuesday as they worked to determine whether she should live or die for her crime. They adjourned after about an hour and resumed Wednesday morning.
If the jury opts for a life sentence, the judge will have the option of determining whether she spends the rest of her days behind bars or is eligible for release after 25 years. Arias acknowledged it was unlikely she would ever be released, but believed she deserves a second chance.
Following her conviction last week, she told a local TV station that she preferred the death penalty. She said Tuesday night that she changed her mind after a tearful meeting with family members the same day, realizing her death would only cause them more pain.
"I felt like by asking for death, it's like asking for assisted suicide, and I didn't want to do that to my family," she told the AP.
Arias said she fought from the beginning to keep cameras out of the courtroom to limit the media spectacle, and believes the jury should have been sequestered. She stated flatly that she did not receive a fair trial.
"The prosecutor has accused me of wanting to be famous, which is not true," she said.
However, Arias has sought the spotlight at every turn, providing TV interviews and even using a third-party to tweet throughout the trial.
Arias repeated her claims that she never wanted to go to trial in the first place but instead wanted to reach a deal with prosecutors on a second-degree murder count that would have carried a maximum of 22 years in prison. However, she said, "no deal was offered."
She talked to reporters Tuesday after the judge lifted an order barring jail officials from accepting any media requests. The judge did not elaborate on the reason for the ruling, but Maricopa County Sheriff Joe Arpaio's office quickly began arranging the interviews that lasted late into the night.
A shackled Arias wore makeup for the interviews and showed up in a jail classroom with a comb in hand as she fixed her hair for the cameras. When pressed for details on some of her conflicting stories, she was mostly evasive, citing advice from her attorneys and possible pending appeals.
She was also asked about the conflicts she had had with her two court-appointed lawyers, Kirk Nurmi and Jennifer Willmott.
Arias said she wanted at least three people called as witnesses who could have testified to having seen bruises on her neck "when I was choked out" by Alexander but she said she was rebuffed by her lawyers. The prosecutor insisted her self-defense claims were an exaggerated attempt to avoid being convicted.
She said her lawyers "felt a little betrayed" and blindsided by her post-conviction interview but that they gave their blessings for Tuesday night's interviews, warning her to be cautious.
Arias said she sometimes wishes she'd never met Alexander, "just because of how ultimately everything ended and I say that for his sake and mine - not just a selfish thing."