Validation of Tool Mark Analysis of Cut Costal Cartilage, Conference Paper

• NCJ Number: 248531
• Author(s): Jennifer C. Love Ph.D; Sharon M. Derrick Ph.D.; Jason M. Wiersema Ph.D.; Charles Peters Ph.D.
• Date Published: April 2011
• Length: 22 pages
• Grant Number(s): 2008-NI-CX-0004
• Agencies: NIJ-Sponsored
• Publication Type: Research Paper

Annotation

This research study was designed to identify and establish potential error rates associated with tool mark analysis of cut marks in costal cartilage.

Abstract

This research set out to identify and establish potential error rates associated with tool mark analysis of cut marks in costal cartilage. Three knives with different blade types were used to make experimental cut marks in costal cartilage of pigs. Each cut surface was cast and each cast was examined by three analysts working independently and employing the generally accepted method of tool mark analysis of cut marks in costal cartilage. The presence of striations, regularity of striations, and identification of primary and secondary striation patterns were recorded for each cast. The distance between each striation was measured. The results showed that striations were not consistently impressed on the cut surface by the blade's cutting edge, and blade type classification by presence or absence of striations led to a 65% misclassification rate. The use of the classification tree and cross validation methods and inclusion of the mean interstriation distance decreased the error rate to approximately 50%.