The U.S. Court of Appeal for the First Circuit ruled that it should overturn his death sentence on five charges, saying the judge erred several times.
Conviction on three of the charges that Tsarnaev was convicted of has been overturned, the panel of three judges said.
But Tsarnaev will not be released from federal prison.
“And to be crystal clear: Because we are affirming the convictions (except the three § 924 (c) convictions) and the many life sentences imposed on those number of calculations (which Dzhokhar did not Dzhokhar will remain in prison for the rest of his life, with the only question remaining being whether the government will end his life by executing him, “the opinion, authoritative by the Judge of the Court of Circuit Ojetta Rogeriee Thompson, says.
The court that ruled Tsarnaev must be given evidence of a new sentence phase.
Tsarnaev̵7;s lawyers had argued that he did not have fair evidence because Boston was the scene of the mayhem. Attorney Daniel Habib argued in December that the jury was made up of people directly affected by the terror plot who had already made up their minds about Tsarnaev.
Surveillance footage showed the brothers carrying pressure cooker bombs in backpacks and walking through the crowd near the finish line of the marathon in what federal prosecutors called a coordinated attack.
Prosecutors said Tamerlan dropped the first bomb, a 6-quarter pressure cooker containing gunpowder, nails and BBs. The bomb killed Campbell, a 29-year-old restaurant manager, and permanently injured several other people who lost their legs.
The second pressure cooker bomb, carried out by Dzhokhar, exploded 12 seconds later and killed two people, Martin and Lu, a graduate student from China.
The bombings stirred manhunt for days that closed the city. The brothers, while driving, killed a Massachusetts Institute of Technology police officer Sean Collier. After stealing an SUV, the two were pursued by police.
Tamerlan died in an explosive firefight with police near Watertown. Dzhokhar was arrested a day later.
CNN’s Mark Morales and Steve Almasy contributed to this report.