Case Information
UNITED STATES DISTRICT COURT FOR THE DISTRICT OF COLUMBIA UNITED STATES OF AMERICA, :
: Criminal Action No.: 19-358 (RC) v. :
: Re Document No.: 22 DEMONTRA HARRIS, :
:
Defendant. :
MEMORANDUM OPINION
D ENYING D EFENDANT ’ S M OTION IN L IMINE TO E XCLUDE E XPERT T ESTIMONY AS TO F IREARM E XAMINATION T ESTING I. INTRODUCTION
Dеfendant Demontra Harris is charged with unlawful possession of a firearm as a person previously convicted of a felony, assault with a dangerous weapon, and possession of a firearm during a crime of violence. Superseding Indictment at 1–2, ECF No. 39. On July 24, 2019, the D.C. Metropolitan Police Department (“MPD”) responded to a report of gunshots and recovered four 9mm shell casings from the incident scene, which were then entered into the National Integrated Ballistic Information Network (“NIBIN”). A witness later provided MPD with a video filmed that night that allegedly shows Mr. Harris holding and then discharging a firearm in the location where the shell casings were later discovered. No firearm was recovered at the time. Roughly six weeks later on September 8, 2019, during a response to a call for service for a person with a weapon, MPD recovered а Glock 17 Gen4 9x19 pistol (“Glock 17”). This recovered firearm was test-fired and the resulting casings were entered into the NIBIN, where a match was identified with the casings recovered on the night of July 24, 2019. The Government then submitted the relevant evidence to an independent firearms examiner for forensic examination. Chris Monturo, a tool mark examiner who operates the Ohio-based forensic services firm Precision Forensic Testing, examined the evidence and concluded in a report that he believed the four recovered casings from the July 24, 2019 incident scene were fired by the recovered Glock 17. See March 14, 2020 Report of Chris Monturo (“Monturo Report”), ECF No. 22-2. The Government intends to call Mr. Monturo to testify regarding these findings at the upcoming trial in this matter.
This opinion addresses Mr. Harris’s
motion in limine
to Exclude Expert Testimony as to
Firearm Examination Testing (“Def.’s Mot.”), ECF No. 22, pursuant to
Daubert v. Merrell Dow
Pharm. Inc
.,
Mr. Harris argues that the field of firearm and toolmark identification lacks a reliable scientific basis and is not premised on sufficient facts or data, is not the product of reliable principles and methods, and was not applied properly by Mr. Monturo to the facts of the case. Def.’s Mot. at 1–2. The Court disagrees, and will admit Mr. Monturo’s testimony to the extent it falls within the Department of Justice’s Uniform Language for Testimony of Reports for the Forensic Firearms/Toolmarks Discipline – Pattern Matching Examination (“DOJ ULTR”). While Mr. Harris raises important issues as to the reliability of firearm and toolmark identification, memorialized most notably by the 2016 President’s Council of Advisors on Science and Technology Report (“PCAST Report”), these issues are for cross-examination, not exclusion, as recent advancements in the field in the four years since the PCAST Report address many of Mr. Harris’s concerns. Mr. Harris also remains free to have his own expert examine the firearm and ballistics evidence and contradict the Government’s case.
II. ANALYSIS
A. Legal Standard
“Motions
in limine
are designed to narrow the evidentiary issues at trial.”
Williams v.
Johnson
,
Federal Rule of Evidence 702 provides that qualified expert testimony is admissible if
“(a) the expert’s scientific, technical, or other specialized knowledge will help the trier of fact to
understand the evidence or to determine a fact in issue; (b) the testimony is based on sufficient
facts or data; (c) the testimony is the product of reliable principles and methods; and (d) the
expert has reliably applied the principles and methods to the facts of the case.” Fed. R. Evid.
702. “In general, Rule 702 has been interpreted to favor admissibility.”
Khairkhwa v. Obama
,
When considering the admissibility of expert evidence under Federal Rule of Evidence
702, district courts are required to “assume a ‘gatekeeping role,’ ensuring that the methodology
underlying an expert’s testimony is valid and the expert’s conclusions are based on ‘good
grounds.’”
Chesapeake Climate Action Network v. Export-Import Bank of the U.S.
, 78 F. Supp.
3d 208, 219 (D.D.C. 2015) (quoting
Daubert
,
“The burden is on the proponent of [expert] testimony to show by a preponderance of the
evidence that . . . the testimony is reliable.”
Sykes v. Napolitano
,
B. Firearm and Toolmark Identification
1. Firearm and Toolmark Identification Science
Mr. Harris’s motion challenges the reliability of the Government’s proposed use of
firearm toolmark identification as a discipline for expert testimony. Firearm identification began
as a forensic discipline in the 1920s,
see
James E. Hamby,
The History of Firearm and Toolmark
Identification
, 31 Ass’n of Firearm and Tool Mark Examiners J. 266, 266–284 (1999), and “for
decades” has been routinely admitted as appropriate expert testimony in district courts.
United
States v. Taylor
,
Firearm and toolmark identification “is used to determine whether a bullet or casing was
fired from a particular firearm.”
Brown
,
A firearm examiner is trained to observe and classify these marks into three types of characteristics during a firearm toolmark examination, which include:
(1) Class characteristics: i.e., the weight or caliber of the bullet, the number of lands and grooves, the twist of the lands and grooves, and the width of the lands and grooves, that appear on all bullet casings fired from the same type of weapon and are predetermined by the gun manufacturer;
(2) Individual characteristics: unique, microscopic, random imperfections in the barrel or firing mechanism created by the manufacturing process and/or damage to the gun post-manufacture, such as striated and/or impressed marks, unique to a single gun; and
(3) Subclass characteristics: characteristics that exist, for example, within a particular batch of firearms due to imperfections in the manufacturing tool that persist during the manufacture of multiple firearm components mass-produced at the same time.
Ricks v. Pauch
, No. 17-12784,
In recent years three scientific reports have examined the underlying scientific validity of
firearm and toolmark identification. They include the 2008 Ballistic Imaging Report, Def.’s
Supp. Mot. Ex. 1, ECF No. 32-1, the 2009 National Academy of Science Report, Def.’s Supp.
Mot. Ex. 2, ECF No. 32-2, and the 2016 President’s Council of Advisors on Science and
Technology Report (“PCAST Report”), Def.’s Supp. Mot. Ex. 3, ECF No. 32-3. Mr. Harris
argues that these reports “reject the claim that firearms identification is a valid and reliable
sciencе.” Def.’s Supp. Mot. at 2–3. The Court is generally convinced by the Government’s
arguments and ample citations to case law that the 2008 Ballistic Imaging Report and the 2009
National Academy of Science Report are both “outdated by over a decade” due to intervening
scientific studies and as a result have been repeatedly rejected by courts as a proper basis to
exclude firearm and toolmark identification testimony. Govt. Supp. Opp’n at 2–4 (collecting
cases holding firearms identification evidence admissible after considering these reports). The
PCAST Report provides better support for Mr. Harris’s arguments, given its more recent origin
and use in recent opinions that have interrogated the danger of subjectivity in this discipline.
See, e.g.
,
United States v. Tibbs
, No. 2016-CF1-19431,
The PCAST Report ultimately concluded that firearm and toolmark identification fell “short оf the criteria for foundational validity,” after raising a number of critiques of the science. PCAST Report at 11. Chief among them was that the report concluded that “foundational validity can only be established through multiple independent black-box studies” [1] and at the time the report was published in 2016, there had only been one black-box study conducted on the discipline to date. Def.’s Supp. Mot. at 4 (citing PCAST Report at 106, 111). In response, the Government has put forth sworn affidavits from researchers that speak to post-PCAST Report scientific studies that they argue contradicts the PCAST Report’s conclusions. The Government’s Daubert hearing expert, Todd Weller, devoted much of his testimony to discussing the scientific advances that have occurred since the PCAST Report was published in 2016, all of which he posited affirms the discipline’s validity. See generally Evid. Hr’g Tr.
2. Mr. Monturo’s Report Methodology
Mr. Harris’s motion in limine specifically challenges the proposed testimony of the Government’s firearm and ballistics expert Chris Monturo, who examined the firearms evidence at issue in this case. In creating his report for the Government, Mr. Monturo first test fired the Glock 17 and found it to be operable. Monturo Report at 2. He then used the Glock 17 to create test-fired cartridge cases. Id. Mr. Monturo then microscopically compared his test-fired cartridge cases to the cartridge cases recovered from the crime scene on July 26, 2019, and found the two sets of cartridges “to have corresponding individual characteristics.” Id . These results were then verified that same day by Calissa Chapin, another qualified firearm and ballistics expert from Mr. Monturo’s lab . March 14, 2020 Report of Chris Monturo Notes (“Monturo Report Notes”) at 3, ECF No. 22-3. As a result, Mr. Monturo is expected to testify thаt “[b]ased upon these corresponding individual characteristics. . . namely aperture sheer marks,” [2] “along with Mr. Monturo’s training and experience, [he] is of the opinion that the Glock firearm fired” the cartridge casings recovered from the July 26, 2019 crime scene. Govt. Opp’n at 11–12.
C. The Subject Matter of Mr. Monturo’s Testimony Meets Rule 702’s Standards Mr. Harris argues that the Government’s proposed expert must be excluded under Rule 702 and because the underlying firearm and toolmark identification discipline “is based not upon science but rather ‘subjectivity.’” [3] Def.’s Supp. Mot. at 2. To address Mr. Harris’s concerns about the admission of Mr. Monturo’s expert testimony, the Court will undertake a factor-by-factor analysis of the discipline’s reliability, using Daubert as a guide. Complicating this process is the fact that Mr. Harris did not specifically address the Daubert criteria in his briefing on this topic, so thе Court will instead rely on the implications raised by the PCAST Report and other scientific reports he has brought to the Court’s attention.
1. Whether the methodology has been tested
As previously noted, the first
Daubert
factor asks whether the technique in question has
been or can be tested.
See Daubert
,
A number of courts have examined this factor in depth to conclude that firearm toolmark
identification can be tested and reproduced.
See, e.g
.,
Otero
,
The fact that there are subjective elements to the firearm and toolmark identification
methodology is not enough to show that the theory is not “testable.” Indeed, studies have shown
that “the AFTE theory is testable on the basis of achieving consistent and accurate results.”
Otero
,
It is also important to note that the tеstability criticism leveled at the firearm and toolmark field in the PCAST Report—that at the time of publishing “there [was] only a single appropriately designed study to measure validity and estimate reliability”—appears to now be out of date. PCAST Report at 112. As previously discussed, the PCAST Report only considered studies that were a “black-box” or “open-set” design, disregarding hundreds of validation studies in the process. See Evid. Hr’g Tr. 48:9-17 (noting that PCAST only evaluated nine of the hundreds of studies that were submitted for review). Setting aside for the moment the utility of this “black-box” requirement— which goes beyond what is required by Rule 702— the Government has provided to the Court three recent scientific studies that meet the PCAST’s black-box model requirements and demonstrate the reliability of the firearm and toolmark identification method. These include one of the tests administered during the Heat Map Study detailеd above, see Weller II at 16 n. 84, along with another recent black box study testing the identification of fired casings, which resulted in a .433% false positive error rate from three errors among 693 total comparisons. See Lilien et al., Results of the 3D Virtual Comparison Microscopy Error Rate (VCMER) Study for Firearm Forensics , J. of Forensic Sci. Oct. 1, 2020 (“Lilien Study”) at 1, ECF No. 41. A third post-PCAST Report study also followed the PCAST recommended black-box model and found that of 1512 possible identifications tested, firearms examiners correctly identified 1508 casings to the firearm from which the casing was fired. Keisler et. al., Isolated Pairs Research Study , Ass’n of Firearm and Tool Mark Examiners J. 56, 58 (2018) (“Keisler Study”), ECF No. 33-9; see also Evid. Hr’g Tr. 65:3-11. This evidence indicates that even under the PCAST’s stringent black-box only criteria, firearm and toolmark identification can be tested and reasonably assessed for reliability.
A final factor demonstrating the strength of the testability prong is that firearm and
toоlmark examiners are required, as Mr. Monturo has done here, to document their results and
findings through written reports and photo documentation, and have these results validated by
another qualified examiner. These elements “ensure sufficient testability and reproducibility to
ensure that the results of the technique are reliable.”
Diaz
,
2. The known or potential error rate
The second factor inquires as to whether the technique has a known or potential
rate of error.
See Daubert,
First, as the Government argues and this Court agrees, the critical inquiry under this
factor is the rate of error in which an examiner makes a false positive identification, as this is the
type of error that could lead to a conviction premised on faulty evidence.
See Otero
, 849 F.
Supp. 2d at 434 (noting, “the critical validation analysis has to be the extent to which false
positives occur”).
[5]
Mr. Weller testified that “over the past couple of decades in research” he had
seen a rate of false positives in research studies ranging from 0-1.6 percent. Evid. Hr’g. Tr.
84:19–22. To support this assertion, the Government provided the false positive error rates for
nineteen firearm and toolmark validation studies conducted between 1998 and 2019, of which
eleven studies had a false positive error rate of zero percent, and the highest false positive error
rate calculated was 1.6%. Govt. Opp’n at 27–29. Other federal courts have also recognized that
validation studies as a whole show a low rate of error for firearm and toolmark identification.
See, e.g
.,
United States v. Romero-Lobato
,
As was the case under the testability prong of the Daubert analysis, here too recent studies have resolved some of the concerns raised by the PCAST Report. Mr. Weller described for the Court how three black box studies that post-date thе PCAST Report all have extremely low rates of error. Govt. Supp. Opp’n at 14, Evid. Hr’g Tr. 65:2-77:8. The Heat Map and Keisler studies both had an overall error rate of zero percent, and the Lilien study produced a false positive rate of only 0.433%. Govt. Supp. Opp’n at 14. Because the evidence shows that error rates for false identifications made by trained examiners is low—even under the PCAST’s black- box study requirements—this factor also weighs in favor of admitting Mr. Monturo’s expert testimony.
3. Whether the methodology has been subject to peer review and publication
The third factor concerns if the methodology has been subject to peer review and
published in scientific journals, a component the Supreme Court emphasized as critical to “good
science” since “it increases the likelihood that substantive flaws in methodolоgy will be
detected.”
See Daubert,
Much of the literature in this discipline has been published in the AFTE Journal, a peer-
reviewed journal that “publishes articles, studies and reports concerning firearm and toolmark
evidence.”
United States v. McCluskey
, No. CR 10-2734 JCH,
Other courts have examined the scientific credibility of the AFTE Journal. Notably, the
court in
Tibbs
concluded that the AFTE Journal’s lack of a double-blind peer review process
along with the fact that it is published by the group of practicing firearms and toolmark
examiners could create an “issue in terms of quality of peer review.”
Tibbs
,
And even if the Court were to discount the numerous peer-reviewed studies published in the AFTE Journal, Mr. Weller’s affidavit also cites to forty-seven other scientific studies in the field of firearm and toolmark identification that have been published in eleven other peer- reviewed scientific journals. Weller II at Ex. A. This alone would fulfill the required publication and peer review requirement.
Because the toolmark identification methodology used by Mr. Monturo has been subject to peer review and publication, the Court finds this Daubert factor to also weigh in favor of admission.
4. The existence and maintenance of standards to control the methodology’s operation
The fourth factor inquires as to whether there are proper standards and controls
to govern the operation of the technique in question.
See Daubert,
The Government identifies a number of what they refer to as “standards for professional
guidance” for the firearm and toolmark profession, Govt. Opp’n at 32–33, but the primary
standard that governs the discipline is the AFTE Theory of Identification, which describes the
methodology examiners should undertake when “pattern matching” between firearms and
cartridges.
See, e.g
., Govt. Opp’n at 8 (explaining that Theory of Identification was created “to
explain the basis of opinion of common origin in toolmark comparisons”). According to the
AFTE Theory of Identification, examiners can conclude that a firearm and cartridges have a
common origin when a comparison of toolmarks shows there is “sufficient agreement” between
“the unique surface contours of two toolmarks.” The Association of Firearm and Tool Mark
Examiners,
AFTE Theory of Identification as It Relates to Toolmarks
, https://afte.org/about-
us/what-is-afte/afte-theory-of-identification (last visited November 4, 2020). This theоry of
identification dictates that “sufficient agreement” between two toolmarks exists only when “the
agreement of individual characteristics is of a quantity and quality that the likelihood another
tool could have made the mark is so remote as to be considered a practical impossibility.”
Id
. The Court finds this standard to be generally vague, and indeed, the AFTE Theory acknowledges
that “the interpretation of individualization/identification is subjective in nature, founded on
scientific principles and based on the examiner’s training and experience.”
Id.
As other courts
have found, under this method “matching two tool marks essentially comes down to the
examiner's subjective judgment based on his training, experience, and knowledge of firearms.”
Romero-Lobato
,
Accordingly, it is evident and hardly disputed that the “AFTE theory lacks objective
standards.”
Ricks
,
It should be noted, however, that even if this factor cannot be met, a partially subjective
methodology is not inherently unreliable, or an immediate bar to admissibility. Rule 702 “does
not impose a requirement that the expert must reach a conclusion via an objective set of criteria
or that he be able to quantify his opinion with a statistical probability.
Romero-Lobato
, 379 F.
Supp. 3d at 1120. And indeed, “all technical fields which require the testimony of expert
witnesses engender some degree оf subjectivity requiring the expert to employ his or her
individual judgment, which is based on specialized training, education, and relevant work
experience.”
Johnson
,
5. Whether the methodology has achieved general acceptance in the relevant community
Finally, the fifth and last factor asks whether the technique has been generally
accepted within the relevant scientific community, reasoning that “a known technique which has
been able to attract only minimal support within the community, may properly be viewed with
skepticism.”
See Daubert,
Mr. Weller testified that firearm and toolmark identification is practiced by accredited laboratories in the United States and throughout the world, including England (Scotland Yard), New Zealand, Canada, South Africa, Australia, Germany, Sweden, Greece, Turkey, China, Mexico, Singapore, Malaysia, Belgium, Netherlands, and Denmark. See Weller II at 30. In the United States alone, there are 233 accredited firearm and toolmark laboratories, that often operate within a larger forensic laboratory providing chemistry, DNA, and fingerprint identification, and scientists from a variety of disciplines author studies within the area of firearms and toolmark identification. Id.
The criticism contained in the PCAST Report does not undermine this factor, as
“techniques dо not need to have universal acceptance before they are allowed to be presented
before a court.”
Romero-Lobato
,
6. The Daubert Analysis Urges Admission оf Mr. Monturo’s Testimony Balancing all five Daubert factors, the Court finds that the Government’s proposed expert testimony of Mr. Monturo is reliable and admissible, though subject to what the Court considers prudent limitations, discussed in detail below. The only factor that does not favor admissibility is the lack of objective criteria under the fourth factor, but as discussed, “the subjectivity of a methodology is not fatal under Rule 702 and Daubert.” Ashburn , 88 F. Supp. 3d at 246. And as other courts have also found, this deficiency “is countered by the method's relatively low rate of error, widespread acceptance in the scientific community, testability, and frequent publication in scientific journals.” Romero-Lobato , 379 F. Supp. 3d at 1122. Accordingly, the Court will allow the admission of Mr. Monturo’s expert testimony as to his firearm and toolmark identification analysis, subject to certain limitations.
D. Federal Rule of Evidence 702(d)
Federal Rule of Evidence 702(d) provides that qualified expert testimony is admissible only when “the expert has reliably applied the principles and methods to the facts of the case.” Fed. R. Evid. 702. Mr. Harris challenges the admission of Mr. Monturo’s testimony, asserting that he “has not applied the principles and methods reliably to the facts of the case.” Def.’s Mot. at 1. However, he provides no evidence or further analysis to flesh out this conclusory claim. Accordingly, the Court finds this argument to be without merit.
As previously described, Mr. Monturo detailed the firearm and toolmark examination he
conducted in his report, providing both a description of his process and photo documentation.
See generally
Monturo Report. Mr. Monturo’s findings were then verified by another qualified
examiner the same day. Monturo Report Notes at 2
.
In contrast, Mr. Harris has not put forth any
evidence to suggest that Mr. Monturo applied the firearm and toolmarking methodology in an
unreliable manner. Mr. Monturo also appears to be well-qualified, with the Government noting
that he “has significant training and experience, has not failed any proficiency exams, and has
designed consecutively manufactured firearms test kits for training other firearms examiners,”
information that they plan to elicit at trial during qualification of his testimony and also set out in
his curriculum vitae. Govt. Opp’n at 35. In light of his failure to identify any unreliability on
Mr. Monturo’s part, and also because Mr. Harris will have the ability to question Mr. Harris
regarding his analysis during cross examination, the Court is convinced exclusion on this ground
is not warranted.
See Daubert,
E. Federal Rule of Evidence 403
Next, Mr. Harris argues that even if the proposed testimony of Mr. Monturo is admissible pursuant to Daubert and Federal Rule of Evidence 702, it is inadmissible under Federal Rule of Evidence 403. Def. Mot. at 2. In support of this claim, Mr. Harris argues that Mr. Monturo’s “conclusions appear to extend beyond his claimed expertise and are not reliable since they are not based on objective standards but rather his subjective observations and conclusions.” Id . “The prejudice to Mr. Harris is simple, a connection to a firearm, a connection to a shell casing, all premised on analysis that at its best can only conclude that it ‘may’ be correct.” Def. Supp. Mot. at 2.
Under Rule 403, a Court may exclude otherwise probative testimony if its value is substantially outweighed by unfair prejudice, confusing the issues, misleading the jury, undue delay, a waste of time, or cumulative evidence. Fed. R. Evid. 403. Mr. Harris’s concern under Rule 403 appears to be that the value of Mr. Monturo’s testimony will be substantially outweighed by the risk of him potentially misleading the jury through his reliance on a methodology Mr. Harris does not believe is sufficiently reliable. First, Mr. Harris’s concerns about the reliability of the firearm and toolmarking methodology have already been analyzed, and the Court has found the underlying analysis sufficiently reliable such that Mr. Harris’s concerns do not “substantially outweigh” the value of Mr. Monturo’s testimony. Additionally, the Court believes that the risk of prejudice raised here can be alleviated through alternatives to exclusion. Cross-examination of Mr. Monturo’s testimony, in conjunction with the appropriate limiting instruction governing the degree of certainty Mr. Monturo can express about his conclusions will sufficiently deter the risks of harm Mr. Harris has raised.
F. Limiting Instruction
In his final request, Mr. Harris asks that if the testimony of Mr. Monturo is not excluded, then the Court put in place limitations on his testimony. Def. Supp. Mot. at 6–7. Specifically, he requests that Mr. Monturo not “use the term ‘match’” but he “may be allowed to tell the jury that he could not exclude the gun as the weapon that produced a casing.” Id.
Limitations restricting the degree of certainty that may be expressed on firearm and
toolmark expert testimony are not uncommon.
See, e.g., Romero-Lobato
, 379 F. Supp. 3d at
1117 (noting the “general consensus” of the courts “is that firearm examiners should not testify
that their conclusions are infallible or not subject to any rate of error, nor should they arbitrarily
give a statistical probability for the accuracy of their conclusions”);
Ashburn
, 88 F. Supp. 3d at
249 (limiting expressions of an expert’s conclusions to that of a “reasonable degree of ballistics
certainty” or a “reasonable degree of certainty in the ballistics field.”);
Diaz
,
With respect to Mr. Harris’s stated concerns, the Government has already agreed to a
number of limitations on Mr. Monturo’s testimony, chief among them that he will not use terms
such as “match,” he will “not state his expert opinion with any level of statistical certainty,” and
he will not use the phrases when giving his opinion of “to the exclusion of all other firearms” or
“to a reasonable degree of scientific certainty.” Govt. Opp’n at 12. These limitations are in
accord with the Department of Justice Unifоrm Language for Testimony and Reports for the
Forensic Firearms/Toolmarks Discipline—Pattern Matching Examination.
See
Govt. Opp’n, Ex.
4 (“DOJ ULTR”), ECF No. 28-4. The DOJ ULTR permits firearms examiners to conclude that
casings were fired from the same firearm when all class characteristics are in agreement, and
“the quality and quantity of corresponding individual characteristics is such that the examiner
would not expect to find that same combination of individual characteristics repeated in another
source and has found insufficient disagreement of individual characteristics to conclude they
originated from different sources.”
Id.
at 2–3. This Court believes, as other courts have also
concluded,
see Hunt,
III. CONCLUSION
For the foregoing reasons, Defendant’s Motion to Exclude Expert Testimony as to Firearm Examination Testing, ECF No. 22, is DENIED. An order consistent with this Memorandum Opinion is separately and contemporaneously issued.
Dated: November 4, 2020 RUDOLPH CONTRERAS
United States District Judge
Notes
[1] The PCAST report defined a black-box study as “an empirical study that assesses a subjective method by having examiners analyze samples and render opinions about the origin or similarity of samples.” PCAST Report at 48. Mr. Weller added at the Evidentiary Hearing that a black-box study is one in which there are “question samples [given to examiners] that have a matching known, and question samples that do not have a matching known, and also that each of those comparisons is independent from each other.” October 15, 2020 Evidentiary Hearing Tr. (“Evid. Hr’g Tr.”) 49:6-12.
[2] As defined in the AFTE Glossary, 6 th Edition, a firing pin aperture shear is “[s]triated marks caused by thе rough edges of the firing pin aperture scraping the primer metal during unlocking of the breech.” Govt. Supp. Opp’n, Ex. 15, ECF No. 33-15. It is these individual characteristics Mr. Monturo used to classify the cartridge cases at issue.
[3] Based on remarks such as these and his citation to
United States v. Glynn
, Mr. Harris
appears to be peripherally raising the point that firearm and toolmark identification cannot “fairly
be called ‘science,’”
United States v. Glynn
,
[4] Mr. Harris’s only explicit acknowledgement of this Daubert factor is an assertion in a
parenthetical that the court in
United States v. Green
found that “ballistic evidence fails to meet
Daubert criteria regarding . . . testability.” Def.’s Mot. at 7 (citing
United States v. Green
, 405 F.
Supp. 2d 104, 120–22 (D. Mass. 2005)). But the facts at issue in
Green
were quite different than
the instant case. Green’s holding that the methods at issue could not be tested rested on an
absence of notes and photographs from the initial examination that “made it difficult, if not
impossible” for another expert to verify the examination.
Green,
[5] Perhaps the false negative rate could be important in a case where a defendant asserts his co-defendant (or a third party) was the culprit and examination of that person’s firearm tested negative. But that situation does not apply here.
[6] This factor is, as the Government concedes, “the only Daubert factor that some courts have found lacking” in firearm toolmark identification. Govt. Opp’n at 33. This makes it all the more puzzling that the Government fails entirely to address this factor in its reply.
