United States v. Benson

• Court: Court of Appeals for the Ninth Circuit
• Decided: September 23, 2025
• Docket: 24-2932
• Status: Unpublished

Opinion

NOT FOR PUBLICATION FILED UNITED STATES COURT OF APPEALS SEP 23 2025 MOLLY C. DWYER, CLERK U.S. COURT OF APPEALS FOR THE NINTH CIRCUIT

UNITED STATES OF AMERICA, No. 24-2932 D.C. No. Plaintiff - Appellee, 2:19-cr-00035-DAD-1 v. MEMORANDUM* HENRY BENSON,

Defendant - Appellant.

Appeal from the United States District Court for the California Eastern Dale A. Drozd, District Judge, Presiding

Argued and Submitted September 15, 2025 San Francisco, California

Before: M. SMITH and BUMATAY, Circuit Judges, and BARKER, District Judge.**

Defendant-Appellant Henry Benson appeals his judgment and commitment

order following a jury trial. We have jurisdiction pursuant to 28 U.S.C. § 1291,

and we affirm Benson’s convictions. Because the parties are familiar with the

* This disposition is not appropriate for publication and is not precedent except as provided by Ninth Circuit Rule 36-3. ** The Honorable J. Campbell Barker, United States District Judge for the Eastern District of Texas, sitting by designation. facts of this case, we do not recount them here, except as necessary to provide

context to our ruling.

Benson argues that the district court: (i) abused its discretion by striking his

alleged admission rather than declaring a mistrial; (ii) abused its discretion under

Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579 (1993), by admitting

expert testimony from Special Agent Nehring about guns as a tool of the trade for

drug distribution; and (iii) plainly erred by allowing Nehring to give expert

testimony while testifying as a lay witness. Benson also claims he suffers from

cumulative error. We disagree.

1. We review a district court’s denial of a motion for a mistrial for abuse of

discretion. See United States v. Lemus, 847 F.3d 1016, 1024 (9th Cir. 2016).

When a district court gives an instruction to strike testimony in lieu of a mistrial,

we usually defer to it. See id. Ultimately, “[a] decision to not declare a mistrial

will be reversed only if the improper comment, viewed in the context of the entire

trial, more likely than not materially affected the verdict.” Id. To determine

whether evidence more likely than not materially affected the verdict, we “must

weigh the forcefulness of the instruction and the conviction with which it was

given against the degree of prejudice generated by the evidence.” United States v.

Morris, 827 F.2d 1348, 1351 (9th Cir. 1987) (quoting United States v. Johnson,

618 F.2d 60, 62 (9th Cir. 1980)).

2 24-2932 The district court did not abuse its discretion by striking Nehring’s testimony

rather than declaring a mistrial. In our view, it is not more likely than not that

Benson’s alleged admission materially affected the jury’s verdict. The district

court gave a forceful curative instruction, and Benson overstates the prejudice

stemming from his alleged admission. Notably, the government did not draw

attention to the alleged admission when eliciting it. Instead, it was Benson’s

counsel who prompted Nehring to repeat the statement, and it was the government,

not Benson, that later moved to strike it. While the alleged statement had some

probative force to suggest that Benson possessed the gun in furtherance of a drug

trafficking offense, the government had other admissible evidence to support the

verdict. See id. For example, the government presented evidence demonstrating

the gun’s proximity to a large quantity of pills and pill-making supplies in

Benson’s bedroom. Benson’s closing argument also acknowledged that the

shotgun was not a hunting weapon or an antique, but a “home defense weapon.”

We further conclude that the district court was not required to bar Nehring

from testifying about guns as an expert following Nehring’s improper testimony—

an argument for which Benson provides no authority.

2. The district court did not abuse its discretion under Daubert by admitting

Nehring’s expert testimony about guns as tools of the trade in drug distribution.

Benson argues that the district court improperly used Nehring’s qualifications to

3 24-2932 make determinations about his testimony’s reliability, rather than evaluating its

scientific validity or methodology. We instead conclude that the district court

properly distinguished Nehring’s qualifications from his testimony’s reliability.

See United States v. Holguin, 51 F.4th 841, 853–55 (9th Cir. 2022). It separately

deemed Nehring’s opinions to be reliable and Nehring to be qualified based on his

experience.

It is true that courts often test an expert’s reliability by applying the five

Daubert factors, but the Daubert factors “simply are not applicable to . . .

testimony[] whose reliability depends heavily on the knowledge and experience of

the expert, rather than the methodology or theory behind it.” See United States v.

Hankey, 203 F.3d 1160, 1169 (9th Cir. 2000). “In such cases, the inquiry may

cover whether the expert’s experience supports the expert’s conclusions; whether

the expert’s reasoning is circular, speculative, or otherwise flawed; or whether the

expert’s reasoning is adequately explained.” Holguin, 51 F.4th at 855 (internal

citations omitted). The district court relied on such an inquiry here. A law

enforcement officer is unlike a chemist or physicist; an officer opining about

criminal behavior necessarily must rely on his knowledge or experience.

3. The district court did not plainly err by permitting Nehring to give expert

testimony while testifying as a lay witness. “Plain error is (1) error, (2) that is

plain, and (3) that affects substantial rights.” United States v. Williams, 5 F.4th

4 24-2932 973, 978 (9th Cir. 2021) (quoting United States v. Wang, 944 F.3d 1081, 1085 (9th

Cir. 2019)). “If these three conditions are met, [we] may then exercise [our]

discretion to grant relief if the error seriously affects the fairness, integrity, or

public reputation of judicial proceedings.” Id. (alterations in original) (quoting the

same).

Benson focuses on Nehring’s identification of “microcrystalline cellulose,”

explanation regarding “phenethylamine,” and testimony that: he found “typical

stuff” like a shotgun, money counter, and phones; “we usually wear” “Tyvek suits”

when searching an area; he saw “TP series [pill] presses” “all the time”; pill

presses were “a lot of times” imported into the United States without registration;

and people do not “[n]ormally” front drugs unless they trust each other. In our

view, even if the district court erred in admitting these statements, any error was

not plain.

When distinguishing between lay and expert testimony by law enforcement

officers, few errors are plain. Lay witnesses may offer opinions that are “not based

on scientific, technical, or other specialized knowledge within the scope of” expert

testimony. Fed. R. Evid. 701(c). But this court has noted that “the distinction

between lay and expert testimony [when an officer testifies in a dual role] is a fine

one,” and it may not be plain error for a district court to fail to intervene sua sponte

to demarcate such testimony. United States v. Freeman, 498 F.3d 893, 904 (9th

5 24-2932 Cir. 2007). Benson does not give us reason to find otherwise here. Further,

Benson does not argue that any error seriously affected the fairness, integrity, or

public reputation of judicial proceedings, foreclosing his claim.

4. The cumulative-error doctrine does not alter our analysis. Where there

are not “multiple errors,” “there cannot be cumulative error.” United States v.

Lindsay, 931 F.3d 852, 869 (9th Cir. 2019).

AFFIRMED.

6 24-2932