Jurors in the trial of Boston Marathon bomber Dzhokhar Tsarnaev are to begin hearing evidence about whether he should receive life in prison or the death penalty.
The penalty phase of Tsarnaev's trial will begin in federal court in the city today.
Tsarnaev's lawyers are expected to continue portraying his older brother Tamerlan, 26, who died in a shoot-out with police four days after the bombing as the mastermind of the attack on April 15, 2013.
They say Tsarnaev does not deserve the death penalty because he was just 19 and heavily influenced by his domineering brother.
Prosecutors, however, say Tsarnaev was an equal partner with his brother in the bombing and deserves the ultimate punishment.
Three people were killed and more than 260 injured when twin bombs exploded near the marathon's finish line.
Tsarnaev was convicted of all 30 charges against him on April 8.