RECENT TRENDS IN FIREARMS/TOOLMARKS. June 05, 2012. Ronald L. Singer, M.S. Tarrant County Medical Examiner’s Crime Laboratory Fort Worth, Texas. FIRST, A REFRESHER. FIREARMS IDENTIFICATION. Ammunition Component Comparison Firearm Function Gunshot Residues on Clothes & Hands
June 05, 2012
Ronald L. Singer, M.S.
Tarrant County Medical Examiner’s
Fort Worth, Texas
Frye / Daubert Challenges Based on NAS Report
“… even with more training and experience using newer techniques, the decision of the toolmark examiner remains a subjective decision based on unarticulated standards and no statistical foundation for estimation of error rates.” (pg. 153-154)
“A fundamental problem with toolmark and firearms analysis is the lack of a precisely defined process.” (pg. 155)
First, and most significantly, this study is neither a verdict on the
uniqueness of firearms-related toolmarks generally nor an assessment of the
validity of firearms identification as a discipline.
“Underlying the specific tasks with which the committee was charged
is the question of whether firearms-related toolmarks are unique: that is,
whether a particular set of toolmarks can be shown to come from one
weapon to the exclusion of all others. Very early in its work the committee found that this question cannot now be definitively answered.”
Finding: The validity of the fundamental assumptions of uniqueness
and reproducibility of firearms-related toolmarks has not yet been fully demonstrated.
2010 - 2012
Criminal No. 11-23 (SRC)
U.S. District Court of New Jersey
March 15, 2012
Separate Daubert motions by both Defendants to exclude expert testimony by firearms expert. Both denied.
“… Deady’s expert report and opinion are admissible under Rule 702.”
“… the Court concludes that the Government has demonstrated that Deady’s proffered opinion is based on a reliable methodology. The Court recognizes … that the toolmark identification procedures … do indeed involve some degree of subjective analysis and reliance upon the expertise and experience of the examiner. The Court further recognizes … that claims for absolute certainty … may well be somewhat overblown.”
Nineteen additional challenges
Mendiola – Judge ruled that identification could not be stated as “… to the exclusion of all others …”
Heang – Examiner’s conclusion should be based on certainty level that conveys “…to a reasonable degree of ballistic certainty…”
Love – Examiner could not testify to the absolute or practical certainty of his results.
Anderson – Examiner could declare a firearms “match” to a “reasonable degree of certainty within the field of firearms identification,” or to a “practical certainty” but may not opine that it is a “practical impossibility” or a “virtual impossibility” that another firearm could have imparted the markings.
Berg & Reed – Expert could testify as to “his opinion based on a reasonable degree of certainty in the ballistics field…” and that expert could not advise of any statistical evidence or present probabilities of a match.
APO AE 09107
U.S. Army Trial Judiciary, Fifth Judicial Circuit, Germany
Defense moved to exclude the opinion of the firearm examiner that a specific cartridge case was fired by a specific AK-47
“Considering the Daubert factors in light of Mrs. Sevigny’s anticipated testimony, the Court finds that any testimony indicating that the shell casing must have come from the AK-47 would be unreliable. While it is clear that Mrs. Sevigny has training and expertise in identifying toolmarks that would undoubtedly assist the trier of fact in this case, the subjective nature of the process,
lack of quantitative standards, and limited scope of foundational testing do not demonstrate the scientific principles necessary to establish the origin of the marks with any specific amount of certainty.”
RONALD L. SINGER, M.S.
Tarrant County Medical Examiner’s Office
Fort Worth, Texas USA