Cross Examination: Firearm/Toolmarks...
Transcript of Cross Examination: Firearm/Toolmarks...
Dylan Ford &
Erin Morris, Ph.D.
Los A ngeles County Public Def end er’s Of f ic e
Cross Examination:Firearms/Toolmarks Examiner
September 18, 2011
This project was supported by Award No. 2010-DN-BX-K259 awarded by the
National Institute of Justice, Office of Justice Programs, U.S. Department of
Justice.
Case Background
Charges:
Murder
Attempted Murder
Possession of Firearm by a Felon
Relevant Firearm/Toolmarks Facts:
No firearm recovered
One bullet and two fired cartridge cases recovered from the scene of the homicide
One bullet recovered by the coroner
One unfired cartridge allegedly found in client’s hotel room
The Prosecution Expert
“Product Overview ”
“Perfect for Crime Scene Investigation
and Forensic Science!”
The Prosecution Expert
Direct Examination
Qualifications
B.Sc. Forensic Chemistry, M.Sc. Criminalistics (Cal State LA)
30 years in criminalistics
Member of AAFS, CAC, AFTE
Forensics instructor for US gov’t, LA Sheriff, local colleges
Over 10,ooo analyses on firearms and firearm-related material
Competitive shootist
Firearm mechanics, comparison fundamentals
Cycling marks
General Rifling Characteristics
Individual characteristics
Direct Examination
Quality Assurance
Peer review, Lab accreditation
Evidence Analysis, Conclusions
2 fired 9mm cartridge cases BOTH CARTRIDGE CASES HAD SUFFICIENT AGREEMENT IN THE UNIQUE
CHARACTERISTICS ON THE BREECH FACE AND THE FIRING PIN IMPRESSION WHERE I CONCLUDED THAT THEY WERE FIRED IN THE SAME FIREARM.
9mm live Luger cartridge THIS PARTICULAR CARTRIDGE …WAS CYCLED THROUGH THE SAME FIREARM THAT
FIRED THE TWO CARTRIDGE CASES
Coroner’s bullet
…THE CORONER'S BULLET HAD THE SAME FEEDING MARKS AS THE [LIVE]
CARTRIDGE. …IT WAS WORKED THROUGH THE ACTION OF THE SAME FIREARM THAT FIRED THE CORONER'S BULLET.
Cross Examination
Three Basic Themes:
A Layperson’s Critique
Using the expert’s photographic documentation simply to point out differences in the compared items that are obvious to the naked eye
Problems Identified by Other Practitioners
Using articles by other firearms and toolmarks analysts who admit there are challenges to accurate identifications
The NRC Report Findings
Using questions with the simple goal of having expert confirm the NRC’s critique of the current status of the FATM art form
Cross Examination: A Lay Critique
Cross Examination: A Lay Critique
Cross Examination: Insiders’ Critique
Cross Examination: The NRC Findings
Cross Examination: The NRC Findings
Cross Examination: The NRC Findings
Cross Examination: Missed Opportunities
Probing accreditation and audits
Forcing an explanation of markings that do not match
Comparing the testifying expert’s credentials against published AFTE practitioners who raise legitimate critiques of the discipline
Effective elucidation of the NRC project and participants