U.S. flag

An official website of the United States government, Department of Justice.

NCJRS Virtual Library

The Virtual Library houses over 235,000 criminal justice resources, including all known OJP works.
Click here to search the NCJRS Virtual Library

Expert Trigger Pull Uncertainty

NCJ Number
229758
Journal
Forensic Magazine Volume: 6 Issue: 6 Dated: December 2009/January 2010 Pages: 10,12,13,14
Author(s)
Dana Sevigny; Jeff Salyards
Date Published
December 2009
Length
4 pages
Annotation
This article provides advice to forensic laboratories on being comfortable with its uncertainty calculations.
Abstract
When measuring forensic evidence, ISO regulations require that forensic laboratories document how uncertainty in the results was calculated. This article provides advice to laboratories on being comfortable with these calculations. Using trigger pull measurements as an example, three questions are asked to make sure the examiner is using the correct procedures to calculate uncertainty. The article discusses how probability measurements can reduce the uncertainty of the testing results. The authors provide an overview of the ISO requirement regarding laboratory procedures for calculating uncertainty of measurements. The authors next address the final aspect of the examination process, deciding the best way to report the results to reduce the possibility of misrepresentation. Several ethical issues regarding presentation of the findings are discussed. Figures