Jurors in the trial of Boston Marathon bomber Dzhokhar Tsarnaev completed their first full day of deliberations Thursday without answering the toughest question any jury can face: whether the defendant should be sentenced to death.
The panel of seven women and five men was released for the day by US District Court Judge George A. O’Toole Jr. They are due back at US District Court in Boston on Friday to resume their closed-door talks.
Jurors, who are working through a complex 24-page verdict slip meant to guide their decisionmaking, twice asked for clarification from O’Toole on legal issues.
The jury had already spent 45 minutes deliberating Wednesday after receiving instructions from the judge and hearing closing arguments from both sides.
In the closing arguments, prosecutors depicted the 21-year-old defendant as a remorseless terrorist who participated in the April 2013 bombing to make a political statement; defense attorneys portrayed Tsarnaev as the troubled follower of an older brother who brainwashed him into joining his violent plan.
Both sides also reminded jurors — the same panel that convicted Tsarnaev last month — of the emotionally charged testimony and graphic photos of the carnage wreaked by the attack presented during the 10 weeks of testimony.
Defense attorney Judy Clarke said the root cause of the violence was Tsarnaev’s late older brother, Tamerlan.
“Dzhokhar would not have done this but for Tamerlan,” she said. “We’re asking you to choose life. Yes, even for the Boston Marathon bomber. It’s a sentence that reflects justice and mercy.”
Echoing themes of war, prosecutors passionately argued that Tsarnaev was his own man and had chosen to become a jihadist warrior. They portrayed him as part of a disturbing number of young anti-American terrorists.
In a dramatic moment during the government’s closing, prosecutor Steven Mellin stopped talking for a full 20 seconds, creating a strange stillness in the courtroom. He then reminded jurors that it was that amount of time — multiplied by 12 — that Tsarnaev waited and watched before detonating his homemade bomb near the family of 8-year-old victim Martin Richard and others outside the Forum restaurant on Boylston Street.
The two bombs detonated by the Tsarnaev brothers on April 15, 2013, killed Martin Richard, Krystle Campbell, 29, and Lingzi Lu, 23, and injured more than 260 others, including 17 who lost limbs. The brothers also murdered MIT Police Officer Sean Collier several days later in an attempt to steal his gun.
Tamerlan Tsarnaev was killed in a shootout after police stopped the brothers in Watertown. He was both shot by officers and run over by his own brother. Dzhokhar Tsarnaev initially eluded a police dragnet but was caught later the same day.
Patricia Wen can be reached at firstname.lastname@example.org. Follow her on Twitter at @GlobePatty.
Kevin Cullen is a Globe columnist. He can be reached at email@example.com. Follow him on Twitter @GlobeCullen.
Milton J. Valencia can be reached at firstname.lastname@example.org. Follow him on Twitter @miltonvalencia.