Lawyers for Dzhokhar Tsarnaev asked a judge on Friday to dismiss indictments against the Boston Marathon bombing suspect and put on hold further proceedings in the case over concerns about the process of selecting jurors in federal court.
Tsarnaev's attorneys said in a motion that a three-year review they conducted into the makeup of both grand juries and trial juries in the District of Massachusetts turned up "substantial violations" of both the federal jury selection law and a constitutional requirement that juries represent a fair cross section of the population.
Specifically, the lawyers cited an underrepresentation of African-Americans and people over 70 on juries.
Prosecutors say Tsarnaev and his older brother, Tamerlan, set off the two bombs at the Boston Marathon's finish line last year, killing three people and injuring more than 260.
Rules used in the Massachusetts district to select jurors allow people over 70 to opt out of jury service, the attorneys wrote, violating the fair cross section requirement of the U.S. Constitution.
About 96 percent of people age 70 or older who were summoned for duty on the grand jury that indicted Tsarnaev opted out of service, the motion said, and a similar percentage of people over 70 opted out from all juries in the eastern division of the district between 2011-2013.
"Being over age 70, like race, sex and national origin, is an immutable characteristic - one cannot get younger - and exclusion on the basis of such a characteristic gives rise to the appearance of unfairness," the lawyers wrote in the 15-page motion.
The motion also cited a failure in many cases to mail replacement summons for jury service when original summons are returned as undeliverable by the post office. The court's rule requires the clerk to choose, at random, the name of another resident who lives in the same zip code as the one that came back as undeliverable.
In the case of the jury pool that was used to create the grand jury that indicted Tsarnaev, about 5 percent of summons came back as undeliverable, but no replacement summons were sent, the defense claimed.
Federal prosecutors had not yet responded to the motion and an after-hours message left with the U.S. Attorney's office in Boston was not immediately returned.
Defense attorneys asked for dismissal of the indictment and a halt to proceedings in the case pending what they called "reconstitution of the jury wheel."
Tsarnaev has pleaded not guilty to terrorism charges and could face the death penalty if convicted. He is scheduled to go on trial Nov. 3, though his lawyers have said they will likely not be ready by that date.
Tamerlan Tsarnaev was killed during a shootout with police days after the explosion.