United States v. Christopher Weckman, 982 F.3d 1167

On Sept. 25, 2017, a masked robber wearing a blue poncho, striped pants, and gloves demanded money at a Des Moines credit union, displayed a bomb-like device, and took approximately $1,600 that included GPS-enabled "bait bills."
GPS data led officers to a red Ford Explorer occupied by Jennifer Nelson (co-defendant) and Christopher Weckman; Weckman fled on foot with a duffle bag, was captured nearby and said, "You got me." A duffle bag with the device and stolen money was found 20 yards away.
Officers found matching clothing and materials (poncho, striped pants, Ty‑vek tape, circuit boards, batteries, clocks) in the Explorer and at Weckman’s residence; later testing showed the device was not a viable explosive.
A grand jury indicted Weckman for aggravated bank robbery (with lesser‑included bank robbery) and Nelson as an aider/abettor; they were tried jointly. Weckman claimed he lacked knowledge and was a scapegoat; Nelson denied knowing of the robbery.
The jury convicted Weckman of the lesser‑included bank robbery, acquitted Nelson, and the district court sentenced Weckman to 180 months. On appeal Weckman challenged (1) denial of severance, (2) a jury instruction on "intimidation," and (3) the handling of alleged juror misconduct.

Issue	Weckman’s Argument	Opposing Argument	Held
Whether the district court erred by refusing to sever the trials	Nelson’s defense was mutually antagonistic to Weckman’s, creating real prejudice and requiring severance	Defenses were not logically incompatible; government had strong independent evidence; jury could compartmentalize with instructions	No abuse of discretion; no real prejudice; joint trial permissible
Whether the jury instruction converted the objective "intimidation" element into a subjective one	The instruction’s language suggested a subjective standard and misstated the law	The instruction, taken as a whole, articulated the correct objective reasonable‑person test	Plain‑error review: no plain error—instructions as a whole were adequate
Whether the court mishandled alleged juror misconduct (juror gave FBI agent a coin) and should have granted a mistrial	The juror’s unsolicited gift to an FBI agent tainted the jury and residual prejudice required mistrial	The court promptly investigated, dismissed the juror, questioned remaining jurors (who denied contact), and installed an alternate; no evidence of taint	No abuse of discretion in denying mistrial; dismissal and voir dire cured any risk of prejudice

United States v. Nichols, 416 F.3d 811 (8th Cir. 2005) (standard for severance; "real prejudice")
Zafiro v. United States, 506 U.S. 534 (1993) (mutually antagonistic defenses not per se grounds for severance)
United States v. Sandstrom, 594 F.3d 634 (8th Cir. 2010) (antagonistic defenses require severance only if jury will unjustifiably infer guilt from the conflict)
United States v. Poitra, 648 F.3d 884 (8th Cir. 2011) (instructional error review and plain‑error framework when objections not preserved)
United States v. Olano, 507 U.S. 725 (1993) (elements of plain‑error review)
United States v. Hall, 877 F.3d 800 (8th Cir. 2017) (district court has broad discretion handling juror misconduct and mistrial requests)
United States v. Young, 753 F.3d 757 (8th Cir. 2014) (sufficient government evidence can cure potential prejudice from antagonistic defenses)