firearms & toolmark identification
TRANSCRIPT
FIREARMS & TOOLMARKIDENTIFICATION:
FORENSIC PATTERN MATCHING PRACTICES
F O R D H A M C L E – M A R C H 2 3 , 2 0 1 8P R E S E N T E R S : DA N A D E S & S U S A N N A D E L A PAVA
aka “This NYPD
Detective is Not An
Expert in Anything”
aka “How to Try a
Toolmark Case”
WHAT CASES WILL HAVE TOOLMARK EVIDENCE?
•A shooting
•Gun
•Shell casings or spent bullets or bullet fragments
•Any case where a firearm is discharged or someone is shot or fired at, start to think that toolmark may come into play
WHAT DOES IT ENTAIL?
Ballistics comparison at the NYPD lab
Ballistics comparison paperwork packet
Testimony at trial by NYPD Detective
Will claim to be expert in “firearm identification and microscopic comparison”
“REASONABLE DEGREE OF SCIENTIFIC CERTAINTY”
ROADMAP – WHAT TO DO
Try and keep it out (Frye Motion & Citywide Challenge)Keep it out
If it comes in, try and severely limit it (language, scope)Limit
If it comes in, completely discredit itDiscredit
Thematically debunk the “science” at each stage, voir dire, openings, X, etc.Debunk
DEMYSTIFY THE “SCIENCE”
•Scientific Foundations of Forensic Feature-Comparison Methods:
There are NONE
•It is “scientifically indefensible”
TRIBOLOGY
The science and engineering of friction, lubrication, and wear, of materials (generally metals) in contact and in relative motion.
NYPD APPROACH
Ballistics lab
Detectives from the Firearm Analysis Section
AFTE (Association of Firearm and Toolmark Examiners)
Will claim to be experts in microscopically comparing ballistics evidence
NYPD FIREARM EXAMINER TRAINING PROGRAM(FROM DETECTIVE PARLO - BROOKLYN)
25 months
Formal and informal lectures
Practical exercises
Training assignments
Job training with senior examiners
BROOKLYN EXAMPLE – FIREARMS ANALYSIS SECTION
3 different Detectives handle Kings County shooting cases, 2 in every other borough
Example - Detective Matthew Parlo: 18 years NYPD
8 years firearms examiner
As of 2016 , qualified 140 times (never denied expert status)
Has tested 2000 firearms
“thousands” of microscopic exams”
Degree from SUNY Farmingdale – Applied Science Degree in Computer Information Systems and Technology (“vocational degree?” “correct”)
No publications
Claims to have been involved in validation studies
Dan’s X about validation studies v. proficiency exams
BASICS OF FIREARM EXAMINATIONS
Examiners use 2 characteristics: Striations (aka “striae”)
Impressions
NYPD Detectives will claim “the markings left on the shells are UNIQUE to that firearm”
BASICS OF FIREARM EXAMINATIONS
Class characteristics – when manufactured (p. 188 Ades X – Parlo’s gibberish) Barrel – 5 lands and groves
Individual characteristics Experts cannot even agree on what you need for individualizations
East Coast standard = 3-5 “matching” striae
West Coast = 6, or two pairs of 3 “consecutively matching” striae
MICROSCOPY
MICROSCOPY
60k side by side microscope (“comparison microscope”)
Connected by an optical bridge
View objects side by side
MICROSCOPY
Leeds Firearms and Toolmarks Comparison Microscope (LCF)
THE -OSCOPY IS FOR SCIENCE
BRIEF PRIMER ON FIREARMS / TOOLMARK
GUN
BULLET
GUN PARTSNote:
barrel, slide, ejection port, main
spring, breech face, extractor
THREE MARKS
Firing pin marks
Ejector or extractor
marks
Breech face marks
AFTE – “THEORY OF IDENTIFICATION”
“The theory of identification as it pertains to the comparison of tool marks enables opinions of common origin to be made when the unique surface contours of two tool marks are in sufficient agreement” There is nothing empirically testable about a conclusion made from this “theory.”
“SUFFICIENT AGREEMENT”
POSSIBLE CONCLUSIONS
1. Identification – class characteristics match and “sufficient agreement” of individual characteristics
2. Inconclusive – quality and character of marks are lacking
3. Elimination – examiners are told to only say this when different make and model of gun are involved
4. Insufficient – not enough marks for opinion
PROBLEMS
No comprehensive or meaningful validation studies Validation studies claimed by examiners are in fact fatally flawed, improperly designed, lack external
validity, never done blind or double blind
It is not a science – no scientific method used
“Uniqueness” has never been established to exist in a scientific fashion
RESPONSE FROM THE SCIENTIFIC COMMUNITY
NAS (“National Academy of Sciences”) – 2008 and 2009 Reports Forensics (4 year study commissioned by DOJ) 2009 p. S5 “With the exception of nuclear DNA analysis, no forensic method has been rigorously
shown to have the capacity to consistently, and with a high degree of certainty, demonstrate a connection between evidence and a specific individual or source.”
RESPONSE FROM THE SCIENTIFIC COMMUNITY
PCAST (“President’s Council of Advisors on Science & Technology – Report to the President”) – September 2016 p. 11 “Individualizing is not supported by relevant science.”
AFTE Theory of Identification is not a scientific theory
“We are unaware of any study that assesses the overall firearm and toolmark discipline’s ability to correctly/consistently categorize evidence by class characteristics, identity subclass [manufacturing] marks, and eliminate items using individual characteristics.” OSAC Research Needs Assessment Form, p. 64
P. 46 – “Without appropriate estimates of accuracy, an examiner’s statement that two samples are similar, or even indistinguishable, is scientifically meaningless: it has no probative value, and considerable potential for prejudicial impact.”
Finding 6 PCAST: “Firearms analysis falls short of the criteria for foundational validity.”
PROBLEMS
No comprehensive or meaningful validation studies Validation studies claimed by examiners are in fact fatally flawed, improperly designed, lack external
validity, never done blind or double blind
It is not a science – no scientific method used
“Uniqueness” has never been established to exist in a scientific fashion
Completely subjective in nature – no science allows 100% subjectivity All based on the examiner’s training and experience – experience alone cannot show scientific validity.
No way to reliably estimate error rates.
AFTE admits that their Theory of Identification is subjective in nature and relies on the examiner’s “training and experience.”
SUBJECTIVE
ADDITIONAL PROBLEMS
No comprehensive or meaningful validation studies Validation studies claimed by examiners are in fact fatally flawed, improperly designed, lack external
validity, never done blind or double blind
It is not a science – no scientific method used
“Uniqueness” has never been established to exist in a scientific fashion
Completely subjective in nature – no science allows 100% subjectivity All based on the examiner’s training and experience – experience alone cannot show scientific validity. No
way to reliably estimate error rates.
AFTE admits that their Theory of Identification is subjective in nature and relies on the examiner’s “training and experience.”
Bias – law enforcement-run laboratory
BIAS
RATES OF ERROR
Practitioners claim = 0.3% to 1%
Reality Check – 11 studies involving misidentifications, misattributions, etc.) – rates between 2.3% and as high as 28.2%
Case study: Detroit Police Lab Firearms Unit
permanently shut down in 2008 – audit was done
Misidentifications made in 3 out of 33 adjudicated cases
10% error rate was cited in the shutdown
Annually analyzing 1,800 cases a year
THE TIDE IS CHANGING PCAST SUGGESTS RECONSIDERATION
US v. Green, 405 F. Supp2d 104 (D. Mass 2005) – Death penalty case –Daubert standard applied. Federal district court judge expressed concern that firearms identification testimony has historically been admitted without adequate inquiry into the reliability of the testing methods. Court severely limited the testimony because the examiner had compared one gun to one set of bullets
and casings. They were not compared to a wide range of ballistics specimens. The Court described this questionable practice as “an evidentiary show-up, not what scientists consider a blind test.”
“[t]he more courts admit this type of toolmark evidence without requiring documentation, proficiency testing, or evidence of reliability, the more sloppy practices will endure; we should require more.”
THE TIDE IS CHANGING PCAST SUGGESTS RECONSIDERATION
Second Circuit – 2007 decision US v. Williams, 506 F.3d 151 while approving expert testimony in that case cautioned: “We do not wish this opinion to be taken as saying any proffered ballistics expert should be routinely
admitted.” p. 161
Older forensic methods should not be “grandfathered” from the gatekeeping scrutiny of Daubert and Kumho Tire.
US Supreme Court – 2009 Melendez-Diaz (129 S. Ct. 2527) – the Court acknowledged that “serious deficiencies have been found in the forensic evidence used at criminal trials,” cited the 2009 NAS Report and pointed out that there exists:
“subjectivity, bias and unreliability of common tests such as latent fingerprint analysis, pattern/impression analysis, and toolmark and firearms analysis.”
SUMMARY
Firearms/toolmark identification is a 100% subjective pattern-matching process with no objective indicia for how to conduct the examinations or validation and high error rates!
IF IT COMES IN…
In limine to limit language
Never allow “match”
Fight over uniqueness
Opinion should be severely limited - “[specific weapon] could not be eliminated as the firing platform.” US v. Glynn, 578 F. Supp2d 567, 574-575 (SDNY 2008) – Expert only allowed to say that the bullet
was “more likely than not” a match to the firearm in question but “nothing more.”
US v. Willock, 696 F.Supp2d 536, 546-547 (D. Md 2010) – Firearms and toolmark examiner could give opinions and conclusions but “without any characterization as to the degree of certainty with which he holds them.”
BEWARE OF “TECHNICAL REVIEW”
REAL WORLD: JUROR QUESTIONS
Most common question in States (WI, AZ, IN, etc.) that allow jurors to submit questions:
“If firearms identification is such “bad science”, then why has it been used for so long in the courts?”
STRATEGIES: ATTACK THE DISCIPLINE
STRATEGIES: ATTACK THE DISCIPLINE
STRATEGIES: ATTACK THE DISCIPLINE
STRATEGIES: ATTACK THE DISCIPLINE
BEWARE OF THE TEN BARREL TEST
BEWARE OF THE TEN BARREL TEST
STRATEGIES: ATTACK THE PERSON
STRATEGIES: ATTACK THE PERSON
STRATEGIES: ATTACK THE PERSON
STRATEGIES: ATTACK THE PERSON
STRATEGIES: ATTACK THE PERSON
STRATEGIES: ATTACK THE EVIDENCE
STRATEGIES: ATTACK THE EVIDENCE
STRATEGIES: ATTACK THE EVIDENCE
STRATEGIES: ATTACK THE EVIDENCE
STRATEGIES: ATTACK THE EVIDENCE
STRATEGIES: ATTACK THE EVIDENCE
STRATEGIES: ATTACK THE EVIDENCE
STRATEGIES: ATTACK THE EVIDENCE
STRATEGIES: ATTACK THE EVIDENCE
STRATEGIES: ATTACK THE EVIDENCE
X
X
STRATEGIES: ATTACK THE EVIDENCE
STRATEGIES: ATTACK THE EVIDENCE
STRATEGIES: ATTACK THE EVIDENCE