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A Logical Framework for Forensic DNA Interpretation

NCJ Number
Genes Volume: 13 Issue: 6 Dated: 2022 Pages: 957
Date Published
May 2022
26 pages

This article presents the development of a logical framework for forensic interpretation that will provide guidance to DNA scientists on how they can report balanced and transparent findings.


The forensic community has devoted much effort over the last decades to the development of a logical framework for forensic interpretation, which is essential for the safe administration of justice. The authors review the research and guidelines that have been published and provide examples of how to implement them in casework. After a discussion on uncertainty in the criminal trial and the roles that the DNA scientist may take, the authors present the principles of interpretation for evaluative reporting. The authors show how their application helps to avoid a common fallacy and present strategies that DNA scientists can apply so that they do not transpose the conditional. The authors then discuss the hierarchy of propositions and explain why it is considered a fundamental concept for the evaluation of biological results and the differences between assessing results given propositions that are at the source level or the activity level. The authors show the importance of pre-assessment, especially when the questions relate to the alleged activities, and when transfer and persistence need to be considered by the scientists to guide the court. The authors conclude with a discussion on statement writing and testimony. This provides guidance on how DNA scientists can report in a balanced, transparent, and logical way. (Published Abstract Provided)

Date Published: May 1, 2022