Uncertainty and Limitations of Probabilistic Genotyping Systems

Has a person of interest contributed DNA to a mixture obtained from evidence? Is that DNA associated with a crime? Both are questions that cannot be answered with absolute certainty. This module of the Probabilistic Genotyping of Evidentiary DNA Typing Results workshop series addresses the uncertainty and limitations of probabilistic genotyping systems that are used to calculate likelihood ratios and infer genotype sets from DNA typing results. Probabilistic reasoning provides a means to characterize these results, given the unknown information in forensic evidence, the stochastic environment, and sources of variability. Instructors in Module 7 will explore strategies of interpretation and decision making in light of these and other variables, such as the uncertain number of contributors, and will share research on the impact of these variables on the likelihood ratio.

This webinar is part 7 of the Probabilistic Genotyping Of Evidentiary DNA Typing Results Webinar Series and was presented by the NIJ Forensic Technology Center of Excellence on June 26, 2019.

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