To decide Dzhokhar Tsarnaev's punishment for the Boston Marathon bombing, the jury must weigh aggravating factors that prosecutors say support their call for the death penalty against mitigating factors that Tsarnaev's lawyers say support their argument for life in prison.

The judge made a point of saying that it's not a numbers game — for example, if jurors find five aggravating factors and four mitigating factors, they would not be compelled to sentence Tsarnaev to death. Rather, the judge said, their decision should be based on the quality of persuasiveness of the factors. Here is a list of aggravating factors presented by prosecutors and mitigating factors presented by the defense:

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AGGRAVATING FACTORS

— Tsarnaev knowingly created a grave risk of death to one or more persons in addition to the victims of the offense.

— The death occurred during the commission and attempted commission of and during the immediate flight from the commission of another offense.

— Tsarnaev committed the offense in an especially heinous, cruel and depraved manner in that it involved serious physical abuse to the victim.

— Tsarnaev committed the offense after substantial planning and premeditation to cause the death of a person and commit an act of terrorism.

— Tsarnaev intentionally killed and attempted to kill more than one person in a single criminal episode.

— Tsarnaev is responsible for the death of 8-year-old Martin Richard, who was particularly vulnerable because of his youth.

— In conjunction with committing acts of violence and terrorism, Tsarnaev made statements suggesting that others would be justified in committing additional acts of violence and terrorism against the U.S.

— Tsarnaev caused injury, harm and loss to the four people killed, including three in the bombings and Massachusetts Institute of Technology police Officer Sean Collier days later.

— Tsarnaev targeted the marathon — an iconic event that draws large crowds of men, women and children to its final stretch — making it especially susceptible to an act of terrorism.

— Tsarnaev has demonstrated a lack of remorse.

— Tsarnaev murdered a law enforcement officer while he was performing his official duties.

— Tsarnaev participated in additional uncharged crimes of violence, including assault with a dangerous weapon, assault with intent to maim, mayhem and attempted murder on April 15, 2013, at the marathon, and on April 19, 2013, in Watertown, during a battle with police.

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MITIGATING FACTORS

— Age: Tsarnaev was 19 at the time of the bombings.

— No prior history of violence.

— Tsarnaev acted under the influence of his older brother, Tamerlan.

— He was particularly susceptible to his older brother's influence, whether it was because of Tamerlan's age, size, aggressiveness, domineering personality, privileged status in the family or other reasons.

— Tamerlan planned and directed the marathon bombing.

— Tamerlan was the person who shot and killed Collier.

— Tsarnaev would not have committed the crimes but for his older brother.

— Tsarnaev's teachers in elementary school knew him to be hardworking, respectful, kind and considerate.

— His friends knew him to be thoughtful, caring and respectful of the rights and feelings of others.

— His teachers and friends still care for him.

— His aunts and cousins still love and care for him.

— His father was mentally ill and had brain damage.

— He was deprived of stability and guidance because of his father's disability.

— His father's illness made Tamerlan the dominant male figure in the family.

— He was deprived of guidance because of his mother's emotional volatility and religious extremism.

— His mother facilitated his brother's radicalization.

— Tamerlan became radicalized first and then encouraged his younger brother to follow.

— His parents returned to Russia in 2012, making Tamerlan the adult in his life.

— He is unlikely to commit any acts of violence in the future while serving a life sentence without the possibility of release.

— The government has the power to severely restrict his communications with the outside world while he is in prison.

— He has expressed sorrow and remorse for what he did and for the suffering he caused.