Why was Dzhokhar Tsarnaev’s death sentence overturned?

Jury selection in a high profile case, not the location of the trial, led to the stunning ruling Friday.

US District Judge George O'Toole spoke during the sentencing phase of the murder trial of Dzhokhar Tsarnaev in a courtroom sketch in Boston April 21, 2015.REUTERS

Throughout the trial of Dzhokhar Tsarnaev, lawyers for the Boston Marathon bomber stood firm behind their argument that he could never get a fair trial in the same city he was accused of terrorizing.

But the location of the trial in the federal courthouse in South Boston was not the problem, an appeals court ruled Friday; it was the failure of the trial judge to weed out potentially biased jurors in such a high-profile case.

“Despite a diligent effort, the judge here did not meet the standards set by [case law],” the three-member panel of the US Court of Appeals in Boston ruled Friday, in overturning the first death sentence handed out for terrorism by a jury in the United States in the post 9/11 world.

Because Tsarnaev faced federal capital charges, the same jury that convicted him for his role in the bombing was allowed to decide his fate, though in a separate trial with a new slate of witnesses. The appeals court decision upholds the conviction of Tsarnaev, who admitted to his crimes. But it means prosecutors will have to decide whether to seek his death at a new sentencing trial, with a new jury, or let Tsarnaev, now 27, serve the rest of his life in prison.

The decision was based on the disclosure that at least two of the 12 jurors did not fully reveal what they knew about the case, or that they discussed it on social media before they were selected to decide Tsarnaev’s fate. But, more importantly, the appeals court found, Judge George A. O’Toole Jr. erred when he refused to ask the jurors deeper questions about the social media posts, instead relying on their claims that they can serve impartially.

Some legal analysts were quick to hail the decision. “Asking the jurors simply what media outlets they followed and how much publicity relating to the offense they were exposed was not enough,” said Carol Steiker, a Harvard Law School professor, in an e-mail. “Rather, there were more specific crucial questions that needed to be answered.”

But Robert Fisher, a former federal prosecutor and now a criminal defense attorney with Nixon Peabody, defended the initial sentencing verdict, and said that the appeals court was too quick to remove a decision from a jury — something he said the higher courts have warned against.

“This was a straightforward case where the defendant is on video blowing up a child and admitted to the crime, so it’s not hard to imagine your average juror would decide in favor of death whether or not they ever read any reporting on the matter,” he said.

George Kendall, a civil rights lawyer who has argued death penalty cases, said the ruling follows well-established points of law required of cases where life or death is at stake. Kendall, who attended the oral arguments before the appeals court, said the ruling “was not a surprise to anyone who was in the courtroom watching.”

“Given all the interest and publicity and the saturation of the investigation through the community, it was imperative that the judge asked the jurors content questions: What did you read, what did you hear?” he said.

Appeals court Judge O. Rogeriee Thompson put it this way: “For one thing, learning that prospective jurors read, say, The Boston Globe daily and have seen a lot of coverage about the case is not the same as learning that they read Globe articles quoting civic leaders saying Dzhokhar should die — statements that could not constitutionally be admitted into evidence.”

Tsarnaev’s trial was among the highest profile cases in Massachusetts history, and one of the few death penalties handed out in a federal court in the state since modern death penalty laws went into effect in the 1990s.

Though 17 of the 30 charges he was convicted of carried the possibility of capital punishment, jurors ultimately agreed to sentence him to death for six of them — specifically for the bomb he placed in front of the Forum restaurant on Boylston Street that killed 8-year-old Martin Richard and Lingzi Lu, a 23-year-old Boston University graduate student from China. His older brother and only known accomplice, Tamerlan, placed the bomb that killed Krystle Marie Campbell, 29, of Arlington. The elder Tsarnaev was killed during a firefight with police in Watertown.

In its 182-page opinion, the appeals court weeded through even the most minute details of Tsarnaev’s five-month trial, conviction, and sentence. It issued several landmark opinions and advisories for the future of the case.

The court ruled, for instance, that O’Toole also erred when he refused to let jurors hear evidence that Tamerlan Tsarnaev had previously killed three people during a robbery in Waltham in 2011. The court agreed with Tsarnaev’s lawyers that the information could have supported their claim that the older brother was a dominating figure who influenced and coerced the younger Tsarnaev into committing the bombings.

The court suggested that it may have demanded a new death sentence hearing based on that decision alone, regardless of the failed juror screening.

“The omitted evidence might have tipped at least one juror’s decisional scale away from death,” the court said.

The court also overturned three of Tsarnaev’s 30 convictions, related to the use of a firearm or explosive, citing a recent US Supreme Court decision that changed the definition of the law applied to those crimes. The dismissal of those cases did not affect the death sentence.

Though it did not issue a ruling, the court also weighed in on the controversial question of whether it will ever be possible to pick a fair, impartial jury in the same city where the bombs went off — one of the key points of litigation during the trial. Two of the three judges suggested it could be possible, noting many potential jurors who were questioned in polls at the time suggested they had not made a decision on the case.

The court noted, for instance, that the jury deliberately sentenced Tsarnaev to death for certain crimes, and not others, showing that they were thoughtful in deliberations. The court said a more properly screened jury could have reached a different verdict.

Because the court went out of its way to assure that Tsarnaev will spend the rest of his life in prison, the key question is whether the government will again seek the death penalty, said John Pucci, a former federal prosecutor in the Springfield area.

To answer that, prosecutors must turn to the victims for their input, he said. But the earlier trial showed that the victims were split.

“It’s a complex problem if you have true victims, totally innocent people, who have been crushed by this, who ask you to do different things,” Pucci said. “How you settle that out and resolve that, believe me, that’s a challenge.”