Gerald R. Grant, Jr.

Gerald R. Grant, Jr. testified for the defense as a computer-forensics investigator, comparing digital records with the locations of bomb-component purchases. On Day 41, he placed phone activity associated with Dzhokhar Tsarnaev around UMass rather than Saugus near the January 31, 2013 pressure-cooker purchase time. For March 6, he found no indication that the phone left the Dartmouth/New Bedford area during the New Hampshire BB purchases. He emphasized that antenna coordinates did not establish a phone's exact location. He also corrected a tweet's time-zone label and placed a 2012 Marathon-day posting at 6:42 a.m. Eastern Daylight Time.

Under Aloke Chakravarty's cross-examination, Grant acknowledged that tweets and university card swipes documented discrete activity rather than continuous whereabouts. Tower plots did not identify who used the phone, and his reviewed data did not corroborate Tamerlan as the BB purchaser. He acknowledged a January 31 text to Tamerlan but qualified his knowledge of other communications. He did not adopt counsel's assertion that AT&T data-usage records were unreliable location indicators. On redirect, he explained coordinate plotting and travel-time estimates, again answering a phone-location question by identifying the tower's location rather than the phone's precise position.

When recalled on Day 53, Grant authenticated Yahoo email records, Tamerlan's YouTube-account pages, and reports extracted from Tamerlan's HTC phone. The admitted email charts covered 21 messages, including personal exchanges, car photographs, religious material, and articles about Sheikh Usamah Bin Laden. Grant explained his verification methods and acknowledged unavailable links and a limited review of one video. He confirmed a user-created playlist named terrorists and Marathon-related web-history entries. The court admitted and played a phone video that Fick described as Tamerlan prompting his daughter to repeat Allahu Akbar, over the government's relevance objection.

On cross-examination, Grant acknowledged that the presented emails were a small selection from approximately 6,000 messages across the two accounts. He had read translated email text but not a translation of a linked article, and qualified his characterization of that article. He had no evidence that Dzhokhar visited Tamerlan's YouTube site. Although the phone log contained 851 calls, Grant had not analyzed recipients or timing and declined counsel's proposed characterization of the proportion involving Dzhokhar.