BOSTON (CBS/AP) – The jury that convicted Boston Marathon bomber Dzhokhar Tsarnaev now must decide whether he will live or die.

Next week jurors will begin the death penalty phase of the trial. They must agree unanimously for Tsarnaev, 21, to receive a death sentence, otherwise the penalty will be life in prison.

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His attorneys are expected to be much more aggressive during the penalty phase, when they will make a case that Tsarnaev’s life should be spared.

Dzhokhar Tsarnaev's attorneys, including Miriam Conrad, (from left), David Bruck and Judy Clarke. (Photo by Scott Eisen/Getty Images)

Dzhokhar Tsarnaev’s attorneys, including Miriam Conrad, (from left), David Bruck and Judy Clarke. (Photo by Scott Eisen/Getty Images)

They claim he was strongly influenced by his radicalized older brother, Tamerlan, who was said to have masterminded the attack.

The defense can present any mitigating evidence it believes will persuade the jury that life in prison is the appropriate punishment rather than death.

During the penalty phase, which could begin as early as Monday, prosecutors will provide evidence of aggravating factors they believe support the death penalty.

They’ve already listed several factors, including the killing of a child, 8-year-old Martin Richard, and the targeting of the marathon because of the potential for maximum bloodshed.

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“We should be prepared for the emotional nature of this to continue. The prosecution won’t leave anything to chance,” said WBZ-TV legal analyst and Nixon Peabody LLP partner Gerry Leone.

“If he is, in fact, sentenced to the death penalty, after the second phase of the trial, there will be numerous levels of appeal seeking relief from that ruling,” Suffolk University Law Professor Chris Dearborn told WBZ NewsRadio 1030.

If the jury decides to sentence Tsarnaev to life in prison he will most likely go to the Supermax facility in Florence, Colorado, about 100 miles south of Denver.

The super-maximum-security federal prison in Florence, Colorado, 100 miles south of Denver. (Photo credit BOB DAEMMRICH/AFP/Getty Images)

The super-maximum-security federal prison in Florence, Colorado, 100 miles south of Denver. (Photo credit BOB DAEMMRICH/AFP/Getty Images)

It is the highest security prison in the nation. It was built 20 years ago to house such notorious criminals as Oklahoma City bomber Terry Nichols and Unabomber Ted Kaczynski.

“He will spend 23 hours a day, locked down in his own cell with no other human contact, no communication. He will be let out one hour a day into a caged recreation cell all by himself then he’ll be taken back to his cell,” attorney David Lane of Killmer, Lane and Newman, told CBS Denver.

Tsarnaev would live in a sound-proof cell with an open shower and toilet, controlled by guards. His bed, stool and a desk will be inside the cell. His food would be delivered by guards he’ll never see.

A former warden called Supermax “a cleaner version of hell.”

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