The 2013 marathon bombing killed three people and left 264 others wounded. In April, the same jury convicted Tsarnaev of all 30 counts brought against him.
Boston Mayor Martin Walsh said he hopes the verdict "provides a small amount of closure to the survivors, families" and others affected by the 2013 marathon bombing.
A federal appeals court reject a request from attorneys representing bombing suspect Dzhokhar Tsarnaev to delay the start of trial, which is scheduled to begin Monday.
Authorities say they'll soon release more information about the individuals and how they may be connected to the two main suspects in the April 15 bombings at the Boston Marathon. Law enforcement sources say at least two of the three may have misled the FBI and disposed of some potential evidence.
Surviving suspect Dzhokhar Tsarnaev has been charged with using a weapon of mass destruction to kill three people and wound more than 200 at the Boston Marathon.
After a massive Boston-area manhunt for the suspect in the marathon bombings, police closed in on a boat in a Watertown backyard where the 19-year-old was hiding. The dramatic resolution came shortly after police announced they did not believe the suspect was in the area.