Boston Marathon bomber Dzhokhar Tsarnaev had his death sentence overturned on Friday by a federal appeals court.
However, Tsarnaev'a fate has long remained in limbo, though he was sentenced to die back in 2015 for his role in the fatal April 2013 bombing.
Three people were killed and more than 260 injured when two bombs planted by Tsarnaev and his brother exploded at the finish line.
"Dzhohkar Tsarnaev's death sentences on Counts 4, 5, 9, 10, and 14 are vacated, and the matter is remanded to the district court with directions to hold a new penalty-phase trial".
Tsarnaev's lawyers had argued that intense media coverage had made it impossible to have a fair trial in Boston.
US Circuit Judge O. Rogeriee Thompson, writing for the court, said that the trial judge "fell short" in conducting the jury selection process and ensuring it could identify partial jurors exposed to pretrial publicity surrounding the high-profile case.
The bombs tore through the packed crowd and caused many people to lose legs. The appeals judges, in a hearing on the case in early December, devoted a significant number of questions to the juror bias argument.
"By not having the jurors identify what it was they already thought they knew about the case, the judge made it too hard for himself and the parties to determine both the nature of any taint (e.g., whether the juror knew something prejudicial not to be conceded at trial) and the possible remedies for the taint", the judges wrote.
Part of the ruling was a decision to reverse three convictions for charges that Tsarnaev was carrying a firearm in connection with his possession of a pressure cooker bomb.
The judges noted that the Boston court has a longstanding rule obligating such an inquiry.
One juror had said in Twitter posts that that she was "locked down" with her family during the manhunt and retweeted another post calling Tsarnaev a "piece of garbage", but later told the court she had not commented on the case or been asked to shelter in place, the defense said. Tsarnaev was 19 years old when he and his brother, Tamerlan, who was 26 years old at the time, went to Boston's Boylston Street shortly before 3 p.m. on April 15, 2013, to carry out their plot. He was convicted and sentenced to death in 2015 and has served time in a federal supermax prison in Colorado since.