The court ruled that the judge who oversaw the case did not adequately screen potential jurors for bias. One was found to have published 24 tweets following the attack, which killed three and wounded over 260.
A federal appeals court on Friday overturned the death penalty sentence of Boston Marathon bomber Dzhokhar Tsarnaev, saying the judge who oversaw the case did not adequately screen potential jurors for bias.
The three-judge panel of the 1st US Circuit Court of Appeals in Boston upheld much of Tsarnaev's conviction, but ordered a lower-court judge to hold a new trial over what sentence he should receive for the crimes that he was convicted of, which were eligible for the death penalty.
The decision was issued more than six months after arguments were heard in the case.
Tsarnaev's lawyers argued that intense media coverage had made it impossible to have a fair trial in Boston, also citing social media posts made by two jurors, suggesting that they had harbored strong opinions even before the 2015 trial began.
The lawyers said that one of the jurors in question, who went on to become the jury's chief spokesperson, published two-dozen tweets in the wake of the bombings. One of the posts called Tsarnaev a "piece of garbage." They also argued that the case should not have been tried in Boston, where potential jurors were exposed to heavy media coverage of the attack.
US Circuit Judge O. Rogeriee Thompson, writing for the court, said the trial judge "fell short" in conducting the jury selection process and ensuring it could filter through jurors exposed to pretrial publicity surrounding the case.
The judges questioned why the two jurors had not been dismissed or questioned by the judge after the posts came to light, adding that the Boston court has a legal obligation to investigate such cases.
Dzhokar and his brother Tamerlan carried out the April 15, 2013 attack which killed three people and wounded over 260 others. Victims included an eight-year-old and a 23-year-old student.
Following the attack, Dzhokar was convicted on 30 charges, including conspiracy and use of a weapon of mass destruction. His brother, Tamerlan, was killed in a shootout with police days after brothers detonated two pressure-cooker bombs near the marathon finish line.
Three nights after the attack, the brothers attempted to flee the city in a hijacked car and shot dead Massachusetts Institute of Technology police officer Sean Collier.
lc/aw (Reuters, AP)