US

Convicted Boston Marathon bomber's life is on the line as defense argues against execution

  • FILE - This undated file photo released Friday, April 19, 2013, by the FBI shows Dzhokhar Tsarnaev. Tsarnaev’s life is on the line as his lawyers return to federal court to make their case that he should be spared the death penalty. Tsarnaev’s defense team is set to begin presenting witnesses on Monday, April 27, 2015, in the penalty phase of his trial, the stage that will determine whether he is executed or spends the rest of his life behind bars. Tsarnaev, 21, already has been convicted of 30 federal charges in the twin bombings that killed three spectators and injured more than 260 others near the marathon’s finish line on April 15, 2013. Seventeen of those charges carry the possibility of the death penalty. (AP Photo/FBI, File)

    FILE - This undated file photo released Friday, April 19, 2013, by the FBI shows Dzhokhar Tsarnaev. Tsarnaev’s life is on the line as his lawyers return to federal court to make their case that he should be spared the death penalty. Tsarnaev’s defense team is set to begin presenting witnesses on Monday, April 27, 2015, in the penalty phase of his trial, the stage that will determine whether he is executed or spends the rest of his life behind bars. Tsarnaev, 21, already has been convicted of 30 federal charges in the twin bombings that killed three spectators and injured more than 260 others near the marathon’s finish line on April 15, 2013. Seventeen of those charges carry the possibility of the death penalty. (AP Photo/FBI, File)  (The Associated Press)

  • Death penalty protesters stand outside federal court, Monday, April 27, 2015, in Boston, during the penalty phase of the federal trial of Dzhokhar Tsarnaev, who was convicted of the Boston Marathon bombings that killed three and injured 260 people in April 2013. (AP Photo/Justin Saglio)

    Death penalty protesters stand outside federal court, Monday, April 27, 2015, in Boston, during the penalty phase of the federal trial of Dzhokhar Tsarnaev, who was convicted of the Boston Marathon bombings that killed three and injured 260 people in April 2013. (AP Photo/Justin Saglio)  (The Associated Press)

  • Defense attorney Judy Clarke, center, arrives at federal court, Monday, April 27, 2015, in Boston, during the penalty phase of the federal trial of Dzhokhar Tsarnaev, who was convicted of the Boston Marathon bombings that killed three and injured 260 people in April 2013. (AP Photo/Justin Saglio)

    Defense attorney Judy Clarke, center, arrives at federal court, Monday, April 27, 2015, in Boston, during the penalty phase of the federal trial of Dzhokhar Tsarnaev, who was convicted of the Boston Marathon bombings that killed three and injured 260 people in April 2013. (AP Photo/Justin Saglio)  (The Associated Press)

Lawyers for Boston Marathon bomber Dzhokhar Tsarnaev (joh-HAHR' tsahr-NEYE'-ehv's) are returning to federal court to make their case that he should be spared the death penalty.

Tsarnaev's defense team is set to begin presenting witnesses Monday in the penalty phase of his trial — the stage that will determine whether he is executed or spends the rest of his life behind bars.

Tsarnaev already has been convicted of 30 federal charges in the twin bombings that killed three spectators and injured more than 260 others on April 15, 2013. Seventeen of those charges carry the possibility of the death penalty.

Prosecutors are pushing for execution. Their case in this second phase of the trial lasted just three days. Tsarnaev's defense is expected to take up to two weeks.