Silva pleaded guilty to loaning a gun to Dzhokhar Tsarnaev two months before the Boston Marathon bombings took place.
According to the prosecution, the Tsarnaev brothers used the gun in the shooting of Massachusetts Institute of Technology (MIT) officer Sean Collier several days after the bombings.
On May 15, a Boston jury sentenced Tsarnaev to death after he was convicted of all 30 charges for his role in the April 2013 Boston Marathon bombing. Three people were killed and more than 260 injured in the bombings.
Earlier in December, Tsarnaev’s Defense Attorney Miriam Conrad said Tsarnaev should receive a new trial because half of the charges against him were based on language found unconstitutional by a recent US Supreme Court decision.