In papers filed Monday, Tsarnaev's lawyers repeated an previous request to appoint David Bruck, a Virginia lawyer whose client list included Zayd Safarini, serving life for his role in the 1986 hijacking of Pan Am Flight 73 in Karachi, Pakistan; and Mohamed Rashed Daoud al-Owhali, one of four men serving life for the 1998 bombing of the U.S. Embassy in Nairobi, Kenya, the Boston Herald reported.
"If this case did not present 'exceptional circumstances' justifying appointment of an additional lawyer learned in the law applicable to capital cases ... no case would," Clarke wrote in the motion.
Tsarnaev, 19, pleaded not guilty in federal court last week to 30 charges, 17 of which carry the death penalty, arising from the twin bombings near the finish line of the Boston Marathon April 15. Three people died and scores were injured.
His legal team tried to add Bruck in April, but a judge denied the request with a promise to review the decision after the indictment.
Prosecutors have not indicated whether they will pursue the death penalty. The Herald reported last week that U.S. Attorney Carmen M. Ortiz's office sent victims a questionnaire asking them for their thoughts on the death penalty, among other matters.
Tsarnaev's brother Tamerlan, 26, was killed when run over allegedly by Tsarnaev as he escaped a shootout with police following the bombings.