Tsarnaev’s lawyer on the state charges, John Salsberg, was not in court and could not immediately be reached. A message was left at his office.
Federal prosecutors say Tsarnaev and his older brother, Tamerlan Tsarnaev, 26, built two pressure cooker bombs and placed them near the finish line of the marathon. Tamerlan Tsarnaev died following the shootout with police four days after the bombings.
Dzhokhar Tsarnaev faces 30 federal charges, including using a weapon of mass destruction and 16 other charges that carry the possibility of the death penalty.
Collier was shot and killed hours after the FBI released photos and video of the Tsarnaev brothers as suspects in the bombing.