Dzhokhar Tsarnaev has pleaded not guilty to a 30-count federal indictment charging him in twin explosions at last year's marathon. The blasts killed three people and injured more than 260.
Tsarnaev's lawyers say many of the charges are redundant and could sway jurors who will weigh whether to find him guilty and whether to sentence him to death. More than half the charges carry the possibility of the death penalty.
U.S. District Judge George O'Toole Jr. will hear arguments Wednesday.
Prosecutors say Tsarnaev and his brother, Tamerlan, built two pressure cooker bombs and placed them near the finish line. Tamerlan Tsarnaev died following a shootout with police.