A memorial at the site of the first explosion in the Boston Marathon bombing. Defense attorneys say too many people in the potential jury pool have some kind of personal connection to the case. Andrew Burton /Getty Images hide caption

itoggle caption Andrew Burton /Getty Images

This combination of undated photos shows Tamerlan Tsarnaev (left) and Dzhokhar Tsarnaev. During a gunbattle with police days after the Boston bombing, Dzhokhar ran over and killed his older brother. AP/The Lowell Sun & Robin Young hide caption

itoggle caption AP/The Lowell Sun & Robin Young