Her life seemed to pass before her, as she delivered a slideshow presentation -- mostly of family photos -- to the jury on Tuesday. It started off with pictures of her as a toddler wearing pigtails and showed several images from holidays and vacations with family members.
She read a prepared statement for nearly 20 minutes, at times crying.
Arias told jurors that she had been a victim of abuse as an adult and as a child. She had claimed she killed Alexander in self-defense after he hurt her, something evidence failed to substantiate.
She called his murder "the worst mistake" she'd ever made, "the worst thing I've ever done." She couldn't have imagined herself capable of such a grisly crime, Arias told the jury.
"But I know that I was," she said. "And for that I'm going to be sorry for the rest of my life -- probably longer."
Arias pledged to make herself useful to other prisoners and humanity by performing acts of charity from behind bars, if spared. She told jurors Tuesday that she could teach people to read in prison and pledged to dedicate her life to good causes.
She noted she could bring "people together in a constructive and positive way" by participating in various programs, including prisoner literacy initiatives; by her "Survivor" T-shirts, which would benefit victims of domestic violence; and by donating her hair, so it could be used to make wigs for sick children. She showed the jurors several pieces of her artwork.
She told them she would suffer for what she did.
"I'm not going to become a mother because of my own terrible choices," she said. "I won't be at my sister's wedding, when she ties the knot next year."
Attorneys argue life and death
Defense attorney Jennifer Willmott argued Tuesday that Arias' life should be spared.
"We're not talking about whether or not to convict. We're talking about whether or not to kill. And so when we talk about that, it matters that she was 27 years old and she had no criminal history," she said. "It matters that she hadn't done anything wrong in her life before that."
Prosecutor Juan Martinez said pointing to Arias' artwork as evidence that her life should be spared wasn't a valid defense.
"It's an entitlement road that they want you to travel when they talk to you about the fact that she's a good artist," he said. "It doesn't mean anything. All it means is: give her special or preferential treatment."
He argued that jurors should sentence Arias to death.
"You have a duty, and that duty really means that you actually do the honest, right thing, even though it may be difficult," he said.
If Arias is given a sentence of death, she would be the fourth woman on death row in the state of Arizona.
When Alexander died
Arias was living in Yreka, California, when she met Alexander at a business convention in Las Vegas in September 2006. That November, he baptized Arias into the Mormon faith, a ceremony Arias said was followed by anal sex.
Arias became his girlfriend two months later, she testified. They broke up in the summer of 2007, and Alexander began dating other women.