A prosecutor called him "evil," and said he deserved to die.
A defense lawyer said he was mentally ill, and that killing him would be unjust.
Both made their final pleas Thursday regarding the fate of Colorado movie theater gunman James Holmes.
And now a jury — the same jury that convicted him of killing 12 people and injuring 70 in the July 20, 2012 massacre at a midnight screening of "The Dark Knight Rises" — will decide if he receives the death penalty or spends the rest of his life in prison.
The jury began deliberating in the late afternoon after closing arguments from the attorneys.
From the start, the trial has hinged on Holmes' mental health. Two state psychiatrists and two defense psychiatrists testified that he suffered from mental illness.
But in their July 16 conviction, the jury rejected defense arguments that Holmes, who suffers from schizophrenia, met the legal threshold for insanity — not understanding right from wrong.
Arapahoe County District Attorney George Brauchler steered clear of the issue in his closing arguments Thursday. Instead, he focused on the 12 who died. He displayed photos of each of them, described their lives, and replayed a recording of a 911 call in which gunshots and screams can be heard in the background.
Brauchler argued that a sentence of life in prison would fall short.
Twice, he asked the jury: "What is the appropriate sentence for such horror, such evil?"
He answered: "For James Egan Holmes, justice is death."
Defense attorney Tamara Brady objected to Brauchler's use of the word evil, but Arapahoe County Chief District Judge Carlos Samour allowed the prosecutor to continue.
In her closing argument, Brady attacked Brauchler's characterization.
"Because you have to dehumanize someone before you can ask other people to kill him," Brady said. "It is medieval to claim that schizophrenia is the source of evil."
She told the jury that the "weight of a man's life" would soon be in its hands, a decision it should not take lightly.
"The death of a seriously mentally ill man is not justice," she said, "no matter how tragic the case is."
The jury went home for the day at around 5 p.m. (7 p.m. ET) to return at 8:30 a.m. Friday morning.