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U.S. v. Shipp, 422 F.Supp.3d 762 (E.D.N.Y. 2019)

Case (cite)
U.S. v. Shipp, 422 F.Supp.3d 762 (E.D.N.Y. 2019)
New York
Type of proceeding
Type of claim
Type of claim (second claim)
Expert evidence ruling reversing or affirming on appeal:
What was the ruling?
Type of evidence at issue:
Firearms identification
Defense or Prosecution Expert
Name of expert(s) who were the subject of the ruling
Detective Sean Ring
Summary of reasons for ruling
On finding AFTE unreliable: "On balance—because of the concerns raised by the lack of a known error rate with a potential error rate of one false positive per 46 examinations, the circular “sufficient agreement” standard, and, to a lesser extent, the lack of general acceptance in the scientific community—the Government has not demonstrated that the AFTE Theory of Identification is reliable enough to allow Detective Ring to testify that the recovered firearm is the source of the recovered bullet fragment and shell casing. However, these concerns apply specifically and solely to use of the AFTE Theory to conclude that there is an identification, or match, between the test fires from the recovered firearm and the recovered shell casing and bullet fragment. They do not apply to several other aspects of Detective Ring's testimony."
The jurisdiction’s standard for expert admissibility at the time – list all that apply: (Frye), (Daubert), (Post-2000 Rule 702), (Other)
Second standard
Rule 702
Did lower court hold a hearing
Names of prosecution expert(s) two testified at hearing
Names of defense expert(s) who testified at hearing (or None).
Discussion of 2009 NAS Report (NAS2009)
Discussion of 2016 PCAST report (PCAST)
Discussion of error rates / reliability
Frye Ruling
Limiting testimony ruling
Language imposed by court to limit testimony
Ruling based in prior precedent / judicial notice
Daubert ruling emphasizing – which factors – (list 1-5)
All factors
Ruling on qualifications of expert
Ruling on 702(a) – the expert will help / assist the jury
Ruling on 702(b) – the testimony is based on sufficient facts or data
Ruling on 702(c) – the testimony is the product of reliable principles and methods
Ruling on 702(d) – reliable application of principles and methods to the facts of the case


In reviewing this case law, the court notices a tension between Daubert and courts’ tendency to separate the AFTE Theory’s scientific validity and the evidentiary reliability of toolmark analysis.




On limiting testimony: This more restrictive limitation is appropriate given the concerns raised by the PCAST Report about the lesser probative value of certain study designs and the reproducibility and accuracy of an individual examiner’s application of the “sufficient agreement” standard. Placing this limitation on Detective Ring’s testimony will prevent the jury from placing unwarranted faith in an identification conclusion based on the AFTE Theory, which the current research has yet to show can reliably determine, to a reasonable probability, whether separate pieces of ballistics evidence have the same source firearm. However, it will still allow the jury to benefit from Detective Ring’s extensive knowledge and experience examining ballistics evidence.


Therefore, while the purported invalidity of the AFTE Theory does not preclude Detective Ring from testifying, the court seriously considers the PCAST Report’s critiques when assessing the reliability of Detective Ring’s proposed testimony.


The Government is also correct that, without exception, these courts have admitted the expert testimony. Id.; (see also Mem. at 12; Gov’t Opp’n at 14). However, many of these courts have expressed increasing concerns about the scientific validity of toolmark analysis, and have imposed restrictions on the proffered expert testimony


Even though prior decisions have found toolmark analysis to be reliable, it is incumbent upon this court to thoroughly review the critiques of the AFTE Theory found in the NRC and PCAST Reports and to consider whether they merit exclusion of Detective Ring’s testimony or, alternatively, appropriate limitations on his testimony.


NOTE: This case has a very thorough discussion of reliabilitiy