Alberto Sierra to soon learn fate as closing arguments in death penalty trial have wrapped late Monday afternoon

Closing arguments wrapped up late Monday afternoon in the death sentence trial of 42-year-old Alberto Sierra.

"He chose death, at every opportunity, every opportunity, when he could've chosen life, and he could've walked away," prosecutor Abbe Rifkin told the jury.

Closing arguments from both the prosecution and defense lasted all day in a Miami courtroom.

Sierra pleaded guilty in August to the 2012 murders of his wife, 29-year-old Gladys Machado, and her two daughters, 6-year-old Julia Padrino and 3-year-old Daniela Padrino.

Sierra confessed to suffocating the victims with a plastic bag before sexually assaulting Machado and 6-year-old Julia. During the proceedings, the prosecution presented a small mannequin to demonstrate how Sierra killed 3-year-old Daniela.

The defense argued that Sierra's decision-making abilities were permanently altered after he was struck by a car at age 12.

"See the amount of brain space that is missing? That is not a healthy, normal brain. A non-healthy brain has consequences," said defense attorney Khurrum Wahid.

Wahid also told the jury that Sierra was diagnosed with a personality disorder.

"No one chooses to have a mental disorder, just like no one chooses to have brain damage," Wahid said.

Prosecutors argued that the killings were cold and calculated, asking the jury to deliberate on the aggravating factors of the crimes.

"Dr. Seuss of all people said it best. Do you remember what Dr. Seuss said? He has a heart that's two sizes too small," Rifkin said.

Wahid countered by referencing the end of the story: "Do you remember how it ended? It ended with the little girl saying that, even though everyone hates you, she's going to forgive you."

Eight of the 12 jurors are required to recommend the death penalty, though the trial judge will ultimately make the final sentencing decision.