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Just Science: Identification: Just Improvised Explosive Devices

NCJ Number
Date Published
March 2019
2 pages

This sixth episode of the Identification season of the National Institute of Justice's (NIJ's) Just Science podcast series is an interview with Hillary Daluz, an instructor for Tritech Forensics and author on latent print analysis, who discusses contextual bias, the difficulty of identifying fingerprints on improvised explosives, and the importance of partnering with other disciplines.


The interview first focuses on changes that are occurring in latent print examination. Topics addressed include efforts to reduce subjectivity in latent print matches, blind verification, quantitative analysis to provide the mathematical likelihood of a match accuracy, and being trained to explain forensic processes so a lay person (a juror) can understand forensic processes and decisionmaking, thus giving it the appropriate weight as evidence. Contextual bias is also discussed in the interview. This can be countered through training and personal awareness of assumptions related to the context of latent prints for the case. Based on Delux's 14 months in Iraq as a latent print examiner working on the remains of improvised explosive devices (IEDs), she discusses issues in such investigations. She emphasizes the diversity in the parts of such bombs and the importance of considering all remnant parts of and settings for such bombs as potential items that may have latent prints of the person or persons who constructed and/or placed the bomb.

Date Published: March 1, 2019