The federal government is appealing a lower court ruling that overturned Dzhokhar Tsarnaev's death sentence.

Transcript

RACHEL MARTIN, HOST:

Today the U.S. Supreme Court hears arguments in the case of Dzhokhar Tsarnaev for his role in the 2013 terrorist bombing at the Boston Marathon. Tsarnaev received the death penalty, but that sentence was overturned by a lower court. We want to warn you this report contains some disturbing audio. Here's NPR legal affairs correspondent Nina Totenberg.

NINA TOTENBERG, BYLINE: Patriot's Day - April 15 - dawned with perfect weather for the annual running of the Boston Marathon. As one writer reported, while the runners climbed Heartbreak Hill, at Fenway Park the Red Sox were locked in yet another white-knuckled duel with the Tampa Bay Rays. By 2:50 in the afternoon, the elite runners had long since ended their runs, the ballgame was over, and many of the Red Sox fans had walked over to the finish line to join the jubilant crowds waiting to greet the last 5,700 runners. Then it happened - two explosions in rapid succession, a fireball, smoke and carnage.

(SOUNDBITE OF EXPLOSIONS, SCREAMING)

TOTENBERG: Three people were killed in the bombing, including an 8-year-old boy, 260 were injured, and severed limbs were everywhere, as medics, police and bystanders raced to stanch the bleeding. Three days later, the FBI released photos of suspects they were seeking - two men later identified as 26-year-old Tamerlan Tsarnaev and his 19-year-old brother Dzhokhar. That night an MIT campus police officer was shot and killed, and the older brother died after a shootout with police. By morning, the hunt for the younger brother riveted the city, as police in the Watertown area went door to door looking for him and telling people to shelter in place.

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UNIDENTIFIED REPORTER #1: If you're just joining us, there was a shootout overnight, and suspect No. 1 in the Boston Marathon terrorist attacks was killed. Suspect No. 2 - on the loose. We're going to take a look...

UNIDENTIFIED REPORTER #2: ...Here in New York, but all eyes are on the situation in Boston.

UNIDENTIFIED REPORTER #3: And welcome back to our continuing coverage of this massive manhunt now underway in Boston. We are just getting word...

TOTENBERG: Later that night, Dzhokhar Tsarnaev was found hiding in a boat under a tarp and covered with blood.

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UNIDENTIFIED PERSON: He's alive. He's in custody. And they're asking for a medic to the scene, which means...

TOTENBERG: Though Massachusetts has no death penalty, two years later a jury convicted Dzhokhar on 30 federal terrorism-related charges. The jury sentenced him to death for six of the crimes. But in July 2020, the U.S. Court of Appeals based in Boston overturned the death sentences. The unanimous panel said that a core promise of our criminal justice system is that even the very worst among us deserves to be fairly tried and lawfully punished. Despite a diligent effort, the appeals court said, the trial judge did not meet that standard. The Justice Department quickly expedited an appeal to the U.S. Supreme Court, and President Trump called the appeals court decision ridiculous.

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DONALD TRUMP: I see in Boston where you have the animal that killed so many people during the Boston Marathon - they just sent his conviction for the death penalty back to the lower court, so they'll...

TOTENBERG: Although the Biden administration would later halt federal executions to review the government's policy, it has continued to defend the death sentence in the Tsarnaev case. Today there are basically two issues before the Supreme Court, both involving rulings by the trial judge. Unlike the judge in the Oklahoma City bombing case, who moved the trial out of state because of the potentially prejudicial effect on the jurors of pretrial publicity, the judge in the Tsarnaev case concluded that any prejudice in Boston could be dealt with by carefully screening potential jurors. But in arguments before the federal appeals court, the defense asserted that the trial judge did not do that, refusing to probe the potential jurors' social media postings. Defense lawyer Daniel Habib, for instance, pointed to the juror who would ultimately become the foreperson.

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DANIEL HABIB: Juror 286 falsely denied having posted on Twitter that Tsarnaev was a piece of garbage. Another juror, No. 138, falsely denied discussing this case on Facebook, where a friend urged him to play the part, sit on the jury and send Tsarnaev to prison, where he would be taken care of.

TOTENBERG: What's more, Habib said, when the judge was presented with documentary evidence of this alleged misconduct during the selection process, he refused to investigate, concluding that the misstatements were innocent failures to recollect. George Kendall is a defense lawyer who specializes in capital cases.

GEORGE KENDALL: This case is the first case where the court is confronted with an almost unlimited amount of information through social media. And so it was really sort of surprising, to say the least, that when the judge decided, OK, we can do this in Boston, that kind of question was not asked of everyone.

TOTENBERG: The second argument in the case centers on the penalty phase of the trial, where the defense is supposed to be given considerable leeway in presenting mitigating evidence. In this case, the appeals court ruled that the trial judge wrongly excluded evidence of the older brother's involvement in a triple murder two years before the marathon bombing, a murder in which he allegedly slit the throats of three men as an act of jihad on the anniversary of the 9/11 attack. The crime remained unsolved until a month after the marathon bombing, when Tamerlan's phone records led FBI agents to a man who admitted being at the scene of the triple murders with Tamerlan. But the interview turned violent, and the man was shot to death by law enforcement authorities. The defense wanted to introduce the facts of that earlier case by having the FBI agent read from his affidavit for the search warrant. Defense lawyer Habib told the appeals court that would have allowed the defense to contrast Tamerlan and his brutal history with his 19-year-old younger brother, a college student with no prior criminal record.

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HABIB: That evidence was highly relevant to the brother's relative responsibility for these crimes.

TOTENBERG: But prosecutor William Glasser replied that delving into the triple murder would have been a distraction.

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WILLIAM GLASSER: It's too great a leap to conclude that all of this evidence about the Waltham murders and the details of it was relevant to the offense in this case. There's plenty of evidence that he himself was influenced by a radical Islamic ideology and was not under the sway of his brother.

TOTENBERG: All of this will be argued today, just two days after the Boston Marathon was run without incident, for the first time in more than two years since the onset of the pandemic and two days after the Red Sox beat the Rays in yet another nail-biter.

Nina Totenberg, NPR News, Washington.

(SOUNDBITE OF ABSTRAKT IDEA'S "SINCERE SUNSET (NUJABES TRIBUTE)") Transcript provided by NPR, Copyright NPR.