Before JONES, SOUTHWICK, and Oldham, Circuit Judges. Edith H. Jones, Circuit Judge: Thomas Harbarger was convicted of illegally possessing an unregistered firearm, specifically a “destructive device,” under the National Firearms Act (“NFA”). See, e.g., 26 U.S.C. §§ 845(a), 5861(d). Appealing his conviction, Harbarger argues that the NFA is unconstitutionally vague as applied to his case and that the evidence is insufficient to support conviction. After a thorough review of the record, we agree with the latter contention and accordingly REVERSE.[1] BACKGROUND While seeking to aid a man with his broken-down truck on a state highway, a Texas state trooper discovered that the truck was reported stolen and the man, Thomas Harbarger, had an outstanding warrant for failing to report to his parole officer.[2] That trooper arrested Harbarger while a second trooper, who had since arrived, searched the truck. The second trooper found a 7.5-inch-long piece of bamboo, sufficiently narrow that a penny (3/4″ wide) was able to cap one end.[3] On the other end was a short fuse. When questioned about the fused bamboo stick, Harbarger stated that it was one of several he had possessed for the purpose of removing beaver dams. He had already used the others and had forgotten that one remained in the truck. After he was indicted for knowingly possessing an illegal destructive device-type firearm, Harbarger moved to dismiss the indictment by arguing that the statute was vague as applied to the facts. The district court was unmoved and about a year later held a two-day jury trial. At trial, the government’s witnesses included three Bureau of Alcohol, Tobacco, Firearms and Explosives (“ATF”) employees who had analyzed the stick of bamboo. They testified that they found pyrodex inside the device, that one could consider the stick of bamboo a pipe bomb, and that it was possible the bamboo stick would burst if the pyrodex was ignited.[4] When the government completed its case in chief, Harbarger moved for acquittal under Federal Rule of Criminal Procedure 29 on the basis of insufficient evidence. The district court denied the motion. Harbarger then testified in his own defense. Despite his earlier statements, Harbarger testified that an acquaintance had built and ignited the other bamboo sticks. Further, he considered the devices to be like firecrackers, and they made a popping sound. At the conclusion of his case, Harbarger unsuccessfully renewed his motion for a judgment of acquittal. The jury returned a guilty verdict, and the court sentenced Harbarger to 72 months of imprisonment. Harbarger timely appealed. DISCUSSION When a defendant moves for a judgment of acquittal at the close of the government’s case in chief and again at the close of all evidence, his challenge to the sufficiency of the evidence is reviewed de novo, with reasonable inferences drawn in favor of the government. United States v. Williams, 507 F.3d 905, 907-08 (5th Cir. 2007). We may reverse a conviction only if no rational trier of fact could find guilt beyond a reasonable doubt. Jackson v. Virginia, 443 U.S. 307, 317, 99 S. Ct. 2781, 2788 (1979). The determinative issue in this appeal is whether an explosive- containing device falls within the NFA when it is susceptible of both innocent and destructive uses and not clearly designed as a weapon. The NFA criminalizes the possession of an unregistered firearm, 26 U.S.C. § 5861(d), including a “destructive device.” 26 U.S.C. § 5845(a). A destructive device is defined to include “any explosive, incendiary, or poison gas . . . bomb.” 26 U.S.C. § 5845(f). But excluded from that definition is “any device which is neither designed nor redesigned for use as a weapon.” 26 U.S.C. § 5845(f). Other circuits have grappled with the application of these provisions and whether the government provided sufficient evidence to prove a particular explosive-containing device was a “destructive device.” Those cases provide a helpful roadmap. For example, in United States v. Johnson the Seventh Circuit aptly described the problem and the solution: the case law demonstrates a fundamental distinction between devices and components that are, by their very nature, ones that can be used only for illegal purposes and devices and components that could have both a proscribed and a legitimate use. When the destructive nature of the devices or of the component parts is obvious because they are suited only for a proscribed purpose, no inquiry into the intent of the possessor is necessary; when the item or items charged under [the NFA] can serve either a destructive or a salutary purpose, the intent of the possessor becomes important and criminal liability only attaches when the possessor intends to possess a device for destructive purposes. 152 F.3d 618, 627 (7th Cir. 1998).[5] Similarly, the Fourth Circuit has held that “[t]he plain language of the Act, consequently, establishes that other types of explosives, such as commercial black powder or dynamite, are subject to . . . the National Firearms Act depending on their intended use.” United States v. Morningstar, 456 F.2d 278, 281 (4th Cir. 1972). Drawing from these analyses, it is reasonable to conclude that when there is doubt whether a device that has some social value and legal use nonetheless falls within the NFA’s ambit, evidence of scienter or evidence that the device can be used solely for illegal purposes is necessary to sustain a conviction. This court’s decision in United States v. Charles, 883 F.2d 355 (5th Cir. 1989), and the Eleventh Circuit’s decision in United States v. Spoerke, 568 F.3d 1236 (11th Cir. 2009), illustrate how this might be done.[6] In Charles, the defendant asserted that his pipe bombs were not weapons but percussive instruments to stun fish. The government tested his assertion by detonating them. Charles, 883 F.2d at 357. When detonated, Charles’s pipe bombs did not just pop, boom, or create some other innocuous effect as claimed. Id. Instead, they behaved like improvised fragmentation grenades and violently dispersed fragmentation. Id. at 356-57. At trial, the expert who tested Charles’s devices opined that they were not noisemakers but in fact improvised explosive grenades. Id. Just as “one would hardly be surprised to learn that possession of hand grenades is not an innocent act,” Charles was found guilty for possessing improvised pipe bombs that actually worked like grenades. United States v. Freed, 401 U.S. 601, 609, 91 S. Ct. 1112, 1118 (1971) (finding that there was no excuse for possessing a grenade given its obvious nature as a likely regulated instrument of war). Similarly, in United States v. Spoerke, the defendant was prosecuted for possessing plastic pipes filled with explosives. 568 F.3d at 1248. He had admitted to police that the devices were illegal but claimed he had produced them for entertainment purposes. The pipe bombs, he testified, would sink when thrown into water, produce a flash, and create a concussive effect on observers. To rebut this description, the government constructed identical devices and detonated them in the water and on land. Contrary to Spoerke’s testimony, the devices did not sink, they floated. Id. at 1243. Further, when exploded they sent plastic fragments flying. Id. In fact, when attached to a watermelon or placed within a toolbox, the bombs’ detonation would obliterate the attached object and disperse fragments up to 200 feet away. Id. As the court explained, given this and other evidence, the conviction easily withstood a sufficiency challenge. The Spoerke court also explained significant distinctions between that case and an earlier case in which a different explosive device was held not to be proscribed by the NFA. Id. at 1246-47 (discussing United States v. Hammond, 371 F.3d 776 (11th Cir. 2004)). The court made clear that a device is not illegal simply because it explodes; it must also be designed for use as a weapon. Hammond, 371 F.3d at 780. The government’s expert in Hammond testified only that the paper-encased explosive device there could explode and cause damage. Id. Spoerke’s devices, however, could be deemed to be designed as weapons because they had “design features that eliminate any claimed entertainment or other benign value ” Spoerke, 568 F.3d at 1247 (quoting Hammond, 371 F.3d at 781). In this case, the government’s only evidence challenging Harbarger’s testimony that his bamboo stick device was used to scare beavers and destroy their dams (and wasn’t very good even at that) was the conclusional testimony of an ATF expert.[7] The expert’s opinion, however, consisted of his saying that the device would fragment on being ignited, and the eruption of two pennies and a plastic bottle cap, along with the bamboo, could destroy property. Because the device had no “commercial application,” he testified, it must be illegal. But breaking up a beaver dam cannot alone sustain a finding that a flimsy explosive device is designed as a weapon, and these fragments do not resemble in dangerousness the relevant fragmentation in other cases.[8] The deficiency of proof in this case resembles that in Hammond and cannot compare with the evidence offered in Spoerke and Charles. Here, a government agent merely burned off an unknown amount of the powder contained in the bamboo stick. The government did not test the device beyond ascertaining that it contained pyrodex; the government did not create replicas and test those devices; nor did it provide any other meaningful evidence from which the design to create weaponry could be inferred. For example, the government did not establish the amount of powder in the device, the thickness of the bamboo’s bore, the thickness of its wall, testimony of personal experience with other similar bamboo devices, expert testimony describing reports regarding similar bamboo devices, or Harbarger’s knowledge of any of the above information. The government accordingly failed to provide proof that the device was “suited only for a proscribed purpose” or contradicting Harbarger’s expressed “intent of the possessor.” Johnson, 152 F.3d at 627.[9] In light of the government’s wholly conclusionary case that the bamboo device was designed as a weapon or that it had no benign or social value, the conviction cannot stand. The evidence was insufficient to prove that the bamboo stick was an illegal explosive device “designed” as a weapon. Unlike cases involving Molotov cocktails or improvised grenades (e.g. metal, PVC, or ceramic pipe bombs designed to fragment and violently disperse shrapnel or metal fragmentation), no published case has held that a small bamboo device like the one at issue here is prima facie a proscribed destructive device. Accordingly, the judgment of conviction is REVERSED.
