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United States v. Ausby, 436 F.Supp.3d 134 (D.C. 2019)

Case (cite)
United States v. Ausby, 436 F.Supp.3d 134 (D.C. 2019)
District of Columbia
Type of proceeding
Type of claim
Type of claim (second claim)
Expert evidence ruling reversing or affirming on appeal:
What was the ruling?
Error to Admit
Type of evidence at issue:
Firearms identification
Defense or Prosecution Expert
Name of expert(s) who were the subject of the ruling
Cortland Cunningham
Summary of reasons for ruling
Defendant argues that firearms toolmark analysis lacks scientific validity and should be excluded, citing NAS 2008, NAS 2009, and PCAST. The court distinguished this testimony from the testimony criticized in the reports because this expert only testified about class characteristics due to damage to the bullet, and the court states that the reports validate the use of class characterstics. However the court finds that the testimony fails under Daubert because the expert did not explain how he inspected and measured the gun or determined the class characteristics of the gun's barrel. Prosecution set forth three methods the expert could have used, but there is no determination as to which of those methods was actually employed, if any. "In this regard, Cunningham's unavailability, coupled with the destruction of the crucial evidence, makes it impossible to know with certainty whether Cunningham's conclusions were 'based on sufficient facts or data' and the 'product of reliable principles and methods.'" The record also does not say if the results were verified.
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)
(4), (5)
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


“As the government correctly points out, recent cases addressing the admissibility of firearms identification evidence under Daubert have concluded that such evidence is admissible even after considering, in detail, the three scientific studies cited by the defendant. . . . The result here is different because the highly unusual circumstances of this case make full appraisal of the methods of analysis Cunningham used impossible. ”




The court describes the detailed evidentiary hearings from many federal cases and explains that “Such detailed analysis is not possible here, where the government’s proffered expert is unavailable and no evidentiary hearing may be held on the reliability of the specific methods he used because those methods are unknown and now unknowable.”


“these [NAS/PCAST] reports are largely inapposite to Cunningham’s testimony, which assesses class characteristics, not individual characteristics. Indeed, the reports cited *168 by the defendant appear to confirm that the methods used to analyze class characteristics remain valid. ”


NOTE: This appeal was over 40 years after the original trial. When the trial took place, Frye was the controlling standard. The appeal was analyzed under Daubert and 702.