Jennifer Montgomery

Jennifer Montgomery testified for the prosecution as a DNA analyst, reporting matches to Officer Sean Collier in exterior glove samples and stains on a Honda Civic key card. On Day 35, the court accepted her as a DNA expert without objection. She explained laboratory procedures and technical review, then compared glove samples with Collier's head-hair reference profile. A left-glove sample contained a mixture whose major male profile matched Collier; the minor profile was insufficient for comparison. Another exterior glove sample yielded a single-source profile matching Collier.

During cross-examination, Montgomery confirmed that eight tested samples from Dzhokhar Tsarnaev's sweatshirt yielded single-source profiles matching him, not Tamerlan Tsarnaev or Collier. At Timothy Watkins's request, she consulted her notes and demonstrated sampling locations on the sleeves, shoulder, abdomen, and back.

On redirect, Montgomery clarified that swabs collect blood from the areas sampled and do not resolve unswabbed or incompletely covered areas. She did not know whether every droplet on the sweatshirt had been sampled, while confirming that the swabs she tested contained no one's blood besides Dzhokhar's. On recross, she identified Stephanie Waite as the sampler and described her as experienced. The court sustained an objection to Watkins's question about relying on Waite to find every testable spot.

Recalled on Day 38, Montgomery confirmed her earlier glove findings and testified that red-brown stains on a Honda Civic key card matched Collier's head-hair reference profile at each tested location. William Weinreb requested Exhibit 914 as an illustrative chart. The defense asked no questions, and Montgomery was excused.