Summary of the Examination Method
The following is a brief summary of the methodology typically used for the comparison of toolmarks which can be summarized by the acronym "ECCCV". ECCCV stands for Evaluation, Classification, Comparison, Conclusion, and Verification. Further detail can be found in sources such as the OSAC Standard "OSAC 2024-S-0002 Standard Test Method for the Examination and Comparison of Toolmarks for Source Attribution", the AFTE/OSAC process map, and individual laboratory procedures.
Evaluation
The assessment of a specimen for features to determine its suitability for further classification and/or comparison.
Classification
The determination of a specimen’s discernible class characteristics, thereby defining the class to which it belongs (e.g., a .45 caliber bullet bearing five groove impressions and right twist).
Comparison
The side-by-side examination of two toolmarks. This comparison may be performed microscopically or macroscopically, as needed.
Conclusion
Opinion stated by an examiner after interpretation of data observed when comparing toolmarks.
Verification
An independent comparison or analysis of items previously examined by the primary examiner to provide a quality check of value determinations or source conclusions.