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Updated: Sep 24, 2025
08:33
A Cross-Disciplinary and Multi-Modal Experimental Design for Studying Near-Real-Time Authentic Examination Experiences
Published on: September 4, 2019
7.1K
Surveying practicing firearm examiners.
Nicholas Scurich1, Brandon L Garrett2, Robert M Thompson3
1University of California, Irvine, USA.
Forensic Science International. Synergy
|May 5, 2022
Summary
Firearm and toolmark examiners spend hours on casework. While most identify firearms, few cite studies for error rates, and views on statistics in testimony are mixed.
Area of Science:
- Forensic Science
- Firearm and Toolmark Examination
Background:
- Firearm and toolmark examination is a critical forensic discipline.
- Understanding current casework practices and examiner perspectives is essential for advancing the field.
Purpose of the Study:
- To survey practicing firearm and toolmark examiners on their casework practices.
- To gather insights into examiners' views on the role of statistics in firearm examinations and expert testimony.
Main Methods:
- A survey was distributed to 79 practicing firearm and toolmark examiners.
- Data collected included time spent on examinations, identification/elimination/inconclusive rates, and opinions on statistical applications.
Main Results:
- Modal time for bullet examination: 2-4 hours; for cartridge casings: 1-2 hours.
- Median examiner identification rate: 65%; elimination rate: 12%; inconclusive: 20%.
- Reported false positive rate: 1%, with limited citation support; mixed views on statistics.
Conclusions:
- Current casework practices show significant time investment and specific outcome distributions.
- A notable gap exists in the empirical support for reported error rates.
- Examiner opinions on integrating statistics into firearm examination and testimony are varied.
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