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Response to "Likelihood Ratio as Weight of Evidence: A Closer Look" by Lund and Iyer

NCJ Number
Forensic Science International Volume: 288 Dated: July 2018 Pages: E15-E19
Date Published
July 2018
5 pages
This article challenges the recent argument presented by Lund and Iyer (L&I) regarding the use of likelihood ratios in court.

The authors of the current article view L&I's argument as based on a misunderstanding of the paradigm. L&I argue that the decision maker should not accept the expert's likelihood ratio without further consideration. This is agreed by all parties. In normal practice, there is often considerable and proper exploration in court of the basis for any probabilistic statement. The current article concludes, however, that L&I argue against a practice that does not exist and which no one advocates. Further, the current article concludes that the most informative summary of evidential weight is the likelihood ratio. The authors state that this is the summary that should be presented to a court in every scientific assessment of evidential weight, with supporting information about how it was constructed and on what it was based. (publisher abstract modified)

Date Published: July 1, 2018