Kimball faced questions about tweet selection and context, Brown described the boat writing and his search, and FBI witnesses explained evidence recovery, custody, and mapping. The Court admitted physical evidence and specified diagram portions, clarified the relevance basis for excluding glove DNA, and arranged a boat inspection.
Full day summary
Cross-examination of Steven A. Kimball focused on the selection and context of Tsarnaev’s tweets. Miriam Conrad contrasted approximately 45 prosecution-selected posts with the complete J_tsar account, which the Court allowed for context rather than truth. Kimball said the prosecution team selected the posts with very little input from him. He confirmed omitted follow-up posts, the March 14, 2013 posting date of a tweet referring to September 10th, and that the displayed April 2012 page did not mention the Boston Marathon. On redirect, he confirmed that all Al_FirdausiA tweets had been introduced. The Court sustained a hearsay objection to a renewed question about Marathon attendance.
Boston Police bomb technician Todd Brown described finding pencil writing inside the Watertown boat while searching for explosive hazards after Tsarnaev’s removal. Photographs and a transcription were admitted without defense objection, and Aloke Chakravarty read passages referring to a brother, religious rewards, U.S. actions, and killing innocent people. On cross-examination, Brown clarified that he did not see Tsarnaev emerge from the boat. He said the holes appeared to run from outside inward, an observation rather than a ballistics conclusion, and that his search found no explosives or weapons.
FBI witnesses described evidence recovery, custody, laboratory intake, and scene mapping. Jeffrey Rolands estimated that more than 450 items were recovered at Scene A. Kristen Koch estimated approximately 3,000 intake items at Black Falcon and explained packaging, seals, tracking, and laboratory transfers. Jason Costello and Paula Ernst described how measurements and evidence records became the Boylston Street diagram, while noting omitted items and grouped, approximate, or generalized locations. During Sarah De Lair’s testimony, the Court admitted Exhibits 42 through 618, with the government’s offer excluding items already admitted. After earlier use as a chalk, specified portions of Exhibit 620 were admitted following clarification of their scope.
Before testimony resumed, the Court clarified that glove DNA had been excluded for insufficient relevance under Rules 402 and 403, not through a Daubert determination, and reserved judgment on possible rebuttal. De Lair’s examination remained unfinished. Outside the jury’s presence, the Court arranged an afternoon boat inspection to help resolve a pending evidence-handling motion.