Nevada Court Finds Firearm Expert’s Opinion Reliable In Spite Of His Subjective Methodology

    Firearms Expert

    Court: United States District Court for the District of Nevada
    Jurisdiction: Federal
    Case Name: United States v. Romero-Lobato
    Citation: 2019 U.S. Dist. LEXIS 80881


    In this case, the defendant was allegedly involved in an attempted armed robbery at the Aguitas Bar and Grill in Sparks in Nevada. During the robbery in question, one of the two robbers (allegedly the defendant) discharged a firearm (Taurus PT111 G2) into the ceiling while escaping. However, no one was apprehended in connection with the incident. Two months later, the defendant allegedly carjacked a person at gunpoint at a Reno-area carwash. The defendant later led officers on a high-speed chase that ended with the defendant crashing the car. The officers found a Taurus PT111 G2 on the front passenger’s seat.

    The Expert

    The state (plaintiff) called a firearm and tool mark analysis expert witness to testify that the gun found at the second incident was the same that was used at first incident. The plaintiff’s firearms expert was a supervising criminalist in the Forensic Science Division of the Washoe County Sheriff’s Office. The defendant objected to the firearms expert, and the court agreed to hold a Daubert hearing.

    Under Daubert, the testimony would only be admissible if it was relevant and reliable. The court observed that the testimony of the plaintiff’s firearms expert was relevant as the expert was set to testify whether the bullet fired from the gun at Aguitas bar was the same as the bullets found in the car.

    Court Discussion – Can The Firearm Expert Withstand A Daubert Hearing?

    With regard to reliability, the first Daubert reliability factor was whether a theory or technique can be tested. The court observed that there was little doubt that the AFTE method of identifying firearms satisfied this Daubert element. The expert testified that he took part in the controlled tests where he determined whether a bullet was fired from a particular gun or not, and he did not make any incorrect identification in these tests. Numerous studies were conducted to test the accuracy and validity of the AFTE method, and these studies weighed in favor of admitting the expert’s testimony.

    The second Daubert reliability factor was whether the technique had been subjected to peer review and publication. During the hearing, the expert testified that the AFTE published its own journal, which was subjected to peer review. Therefore, the peer review and publication factor, therefore, weighed in favor of admissibility.

    The third Daubert reliability factor was whether the technique had a known or potential rate of error. The firearms expert and other federal courts had cited studies that reported a low rate for the AFTE method. The court further observed that the defendant had not submitted any study to counter it. Therefore, this factor weighed in favor of admissibility.

    The fourth Daubert factor was whether there are standards that controlled the technique’s operation. The defendant argued that the AFTE method was not scientific as results could not be quantified or obtained with a numeric probability. The court observed that just because the opinion of the expert was derived from a subjective methodology did not make it unreliable.

    The fifth and final Daubert factor was whether the technique was generally accepted within the relevant community. The court pointed out several instances wherein different courts had observed that the AFTE theory is widely accepted in the forensic science community.


    The court found the testimony of the plaintiff’s firearm expert witness to be reliable and relevant. The expert testified confidently and demonstrated that he had a comprehensive and detailed understanding of both firearms and tool mark examination. Given his substantial training and experience, the cou