skip navigation


Abstract Database

Register for Latest Research

Stay Informed
Register with NCJRS to receive NCJRS's biweekly e-newsletter JUSTINFO and additional periodic emails from NCJRS and the NCJRS federal sponsors that highlight the latest research published or sponsored by the Office of Justice Programs.

NCJRS Abstract

To download this abstract, check the box next to the NCJ number then click the "Back To Search Results" link. Then, click the "Download" button on the Search Results page. Also see the Obtain Documents page for direction on how to access resources online, via mail, through interlibrary loans, or in a local library.


NCJ Number: 250732 Find in a Library
Title: Validation of Toolmark Comparisons Made at Different Vertical and Horizontal Angles
Journal: Journal of Forensic Sciences  Volume:62  Issue:3  Dated:May 2017  Pages:612-618
Author(s): Chad Macziewski; Ryan Spotts; Scott Chumbley
Date Published: May 2017
Page Count: 7
Sponsoring Agency: National Institute of Justice (NIJ)
Washington, DC 20531
Grant Number: 2011-DNR-0230
Document: HTML
Type: Program/Project Description; Report (Grant Sponsored); Report (Study/Research); Research (Applied/Empirical)
Format: Article; Document (Online)
Language: English
Country: United States of America
Annotation: This study involved an analysis of striated toolmarks made as a function of varying vertical and horizontal angles of attack.
Abstract: Numerous studies have focused on determining whether objective statistical methods can be used to discriminate between known matches and nonmatches when comparing laboratory prepared toolmarks. In the current study, comparisons based on experimental data show that replicate toolmarks from the same tool show high correlation values at identical vertical and horizontal angles, with the correlation decreasing as the angular difference increases, especially for horizontal angular changes. Comparisons between non-matching samples produce low correlation values that remain unchanged as horizontal angular differences increase. Although complete statistical separation was not achieved between matching and non-matching samples, there is evidence that toolmarks can be identified if the variation in horizontal angle is within 10 degrees. The experiment shows that computer-aided comparison techniques could be viable for identification with the proper statistical algorithm. (Publisher abstract modified)
Main Term(s): Forensic sciences
Index Term(s): Computer aided operations; Investigative techniques; NIJ grant-related documents; NIJ Resources; Probabilistic evidence; Toolmark identification
To cite this abstract, use the following link:

*A link to the full-text document is provided whenever possible. For documents not available online, a link to the publisher's website is provided. Tell us how you use the NCJRS Library and Abstracts Database - send us your feedback.