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NCJ Number: 149595 Find in a Library
Title: Error and Exaggeration in the Presentation of DNA Evidence at Trial
Journal: Jurimetrics  Volume:34  Issue:1  Dated:(Fall 1993)  Pages:21-39
Author(s): J J Koehler
Date Published: 1993
Page Count: 19
Sponsoring Agency: National Science Foundation
Arlington, VA 22230
Grant Number: SES-9209544
Type: Training (Aid/Material)
Format: Article
Language: English
Country: United States of America
Annotation: This article discusses some of the common exaggerations at trial of DNA-evidence implications and classifies each in relation to three issues in a chain of reasoning.
Abstract: Issues examined in the chain of reasoning are whether a reported match is a true match, whether the suspect is the source of the trace, and whether the suspect is the perpetrator of the crime. Part I of the article examines the first issue and discusses ways of defining and estimating the false positive error rates at DNA laboratories. Parts II and III address the second and third issues, respectively. These sections introduce the "source probability error" and "ultimate issue error" and show how experts often commit these errors at trial with assistance from attorneys on both sides. Part IV introduces two related exaggerations, the "P(another match) error" and the "numerical conversion error." Part V provides a simple and general explanation for the persistence of the errors identified. Part VI concludes with a discussion of the ways in which scientists can take advantage of their roles as teachers, expert witnesses, and researchers to educate the courts about the meaning and limits of probabilistic DNA evidence. 66 footnotes
Main Term(s): Court personnel
Index Term(s): DNA fingerprinting; Police crime analysis training; Science and Technology; Suspect identification
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