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Objective Analysis of Impressed Chisel Toolmarks

NCJ Number
Journal of Forensic Sciences Volume: 60 Issue: 6 Dated: November 2015 Pages: 1436-1440
Date Published
November 2015
5 pages

This study used 50 sequentially manufactured chisels to create impression toolmarks in lead (500 toolmarks total).


The study was prompted by historical and recent challenges to the practice of comparative forensic examination, which has created a driving force for the formation of objective methods for toolmark identification. The current study used an algorithm previously used to statistically separate known matching and non-matching striated screwdriver marks and quasi-striated plier marks to evaluate the chisel marks. Impression toolmarks, a more complex form of toolmark, pose a more difficult test for the algorithm that was originally designed for striated toolmarks. Results show in this instance that the algorithm can separate matching and non-matching impression marks, providing further validation of the assumption that toolmarks are identifiably unique. (Publisher abstract modified)

Date Published: November 1, 2015