Katherine Russell

Katherine Russell appeared in defense testimony about her marriage to Tamerlan Tsarnaev and changes that relatives and friends observed in her relationships. Her mother, Judith Russell, described Katherine becoming less forthcoming about private family matters. On cross-examination, Judith also acknowledged Katherine's independent temperament, long work hours, and continued contact with relatives and a friend. Former roommate Amanda Ransom described their friendship becoming distant and a late-night apartment argument involving screaming and banging, whose precise cause she could not identify. Ransom said she interpreted Tamerlan's subsequent words as a threat and left the apartment. She also recounted Katherine's later message denying that he had threatened her. That denial reached the jury through Ransom's account, not testimony from Katherine.

Evidence associated with Katherine also figured in disputes about household belongings and digital records. Agent Christopher Derks confirmed that numerous documents and objects belonging to her were found in the Norfolk Street apartment. In closing argument, Judy Clarke used Katherine's rental application and pay stub on two thumb drives to argue that the drives came from Tamerlan. Computer examiner Mark Spencer identified Katherine Russell as the MacBook Pro operating-system username and described associated Skype accounts and January 2012 search-history entries concerning rewards for wives of a shahid or mujahidin. His description of the computer history did not attribute those searches to a particular user. Gerald Grant also identified Katherine as an additional recipient of video links Tamerlan emailed to Dzhokhar in April 2012.