926 F.3d 621
10th Cir.2019Background
- Defendant Scott Bishop designed and sold a small metal "TCGTR" kit intended to increase the firing rate of AR-15 rifles; ATF obtained a sample with instructions linking the product to Bishop.
- ATF purchased kits, completed bends per Bishop’s instructions, installed them in AR-15s, and concluded the device caused multiple rounds to fire per single trigger function, meeting the statutory definition of a machinegun.
- Bishop was indicted on (1) unlawfully manufacturing machineguns in violation of 26 U.S.C. § 5861(a) and (2) unlawfully possessing/transferring machineguns in violation of 18 U.S.C. § 922(o); he proceeded pro se at trial.
- At trial the government presented ATF Agent Powell as an expert who demonstrated and opined the TCGTR converted an AR-15 to automatic fire; several customers testified and relayed ATF statements that the device was illegal.
- Bishop testified in his own defense but the district court excluded portions of his testimony explaining technical operation (finding it was undisclosed expert testimony subject to Fed. R. Evid. 702 and Fed. R. Crim. P. 16 disclosure), though Bishop was permitted to testify about his intent.
- The jury convicted on both counts; on appeal Bishop argued improper exclusion of his testimony (violation of right to present a defense), instructional error on mens rea for § 5861(a), admission of hearsay ATF statements, and improper expert testimony on ultimate issues. The Tenth Circuit affirmed.
Issues
| Issue | Bishop's Argument | Government's Argument | Held |
|---|---|---|---|
| Exclusion of Bishop’s technical testimony (Rule 702/16) | Bishop: His explanations were lay testimony about his invention and necessary to present intent defense; exclusion violated right to present a defense. | Gov: Testimony required specialized knowledge, so Rule 702 applied; Bishop failed to disclose under Rule 16, so exclusion was proper. | Court: No abuse of discretion; testimony required specialized knowledge and was expert testimony subject to disclosure; exclusion did not violate constitutional rights because Bishop could still present intent. |
| Mens rea instruction for § 5861(a) | Bishop: Jury instruction (“knew he was manufacturing machineguns”) was ambiguous and failed to require knowledge of the specific physical traits making the device a machinegun. | Gov: Instruction required that Bishop knew the items were machineguns (i.e., modified phrase construed to require knowledge of characteristics). | Court: No plain error; precedent (Mains) treats similar wording as satisfying Staples requirement; instruction not clearly erroneous though better specificity is advisable. |
| Admission of customers’ testimony repeating ATF statements (hearsay) | Bishop: Testimony that ATF told customers the device was illegal was inadmissible hearsay and prejudicial. | Gov: Statements were cumulative of Agent Powell’s detailed expert testimony; any error was harmless. | Court: Plain error standard not met because the hearsay was cumulative of admissible expert testimony and did not affect substantial rights. |
| Expert opinion on ultimate issue (Powell saying device "meets statutory definition") | Bishop: Powell improperly opined on the ultimate legal issue without unpacking technical criteria. | Gov: Rule 704 permits opinions that embrace ultimate issues where expert explains basis; Powell demonstrated and explained how device disabled disconnector and effectuated automatic fire. | Court: No error; Powell gave adequate factual and technical explanation for his conclusion that the device met the statutory definition. |
Key Cases Cited
- Staples v. United States, 511 U.S. 600 (1994) (possession offense requires proof defendant knew the firearm’s characteristic making it a statutory firearm)
- Rogers v. United States, 522 U.S. 252 (1998) (plurality) (jury instruction can be read to require knowledge that item met statutory definition; courts should clarify mens rea in instructions)
- United States v. Mains, 33 F.3d 1222 (10th Cir. 1994) (instruction requiring defendant knowingly possessed firearm with specified characteristics satisfied Staples)
- United States v. Tapaha, 891 F.3d 900 (10th Cir. 2018) (to prevail on exclusion-of-evidence constitutional claim, defendant must show court abused discretion and excluded evidence affected outcome)
- United States v. Yeley-Davis, 632 F.3d 673 (10th Cir. 2011) (distinguishing lay testimony from expert testimony; technical opinions require expert qualification)