CENTENNIAL, Colo., — A jury sentenced James E. Holmes to life in prison with no chance of parole on Friday, rejecting the death penalty for the man who carried out a 2012 shooting rampage that killed 12 people in a Colorado movie theater.

As the courtroom waited for Judge Carlos Samour Jr. to review the verdict, only the sound of him turning pages could be heard. Minutes later, he read each sentence of life, a decision that was a surprise to many in the courtroom.

Since Mr. Holmes was convicted last month of more than 160 counts of murder and attempted murder, his lawyers and prosecutors have been putting questions of his fate before a jury of nine women and three men.

Prosecutors, emphasizing the human toll and indiscriminate cruelty of opening fire on a happy crowd of moviegoers, argued that he should join the three other men on Colorado’s death row. They argued that toll he exacted was so great, and the indiscriminate rampage so horrible, that death by lethal injection was the only just punishment.

But defense lawyers said it was not hatred or a desire for notoriety that propelled Mr. Holmes to plot and carry out the massacre, but a deepening form of schizophrenia that infected his mind with powerful delusions that killing people somehow increased his “human capital.”

To reach a death sentence, jurors had to agree unanimously. If even one person dissents, the sentence is life in prison.

Jurors deliberated for less than a day before reaching their conclusion. They had walked to the precipice of sentencing Mr. Holmes to death, agreeing after earlier sentencing deliberations that he was eligible to receive the death penalty.

But defense lawyers emphasized that jurors had no legal obligation to sentence him to death, and they urged jurors to listen to their own moral compasses no matter what other jurors wanted.

Source: The New York Times, Jack Healy, August 7, 2015