When Is a Drug a Weapon? The Legal Puzzles of Designating Fentanyl a ‘Weapon of Mass Destruction’

On Dec. 15, 2025, President Trump issued an executive order designating illicit fentanyl and its core precursor chemicals as “weapons of mass destruction.” The order’s central claim—that “illicit fentanyl is closer to a chemical weapon than a narcotic”—rests on fentanyl’s extraordinary toxicity: 2 milligrams, an amount equivalent to a few grains of salt, constitutes a potentially lethal dose. The order directs various agencies to take action against fentanyl trafficking using “the full array of appropriate counter-fentanyl tools,” including relevant weapons of mass destruction (WMDs) authorities.

The designation is not purely symbolic. It invokes specific statutory frameworks—most prominently, 10 U.S.C. § 282, which authorizes federal military assistance in domestic “emergency situations involving weapons of mass destruction.” But it also raises questions about whether fentanyl could fit the legal definitions of WMDs scattered across federal law—and what consequences might flow from the executive branch treating it as such.

The Statutory Landscape 

Federal law contains no unified definition of “weapons of mass destruction.” Instead, Congress has enacted at least four distinct statutory definitions across different titles of the U.S. Code. Of note, the executive order does not specify which definition it invokes, although it references several of the defining statutes indirectly.

The core tension runs between two approaches. Some statutes define WMDs by type—essentially listing categories of weapons without requiring any particular scale of harm. Others define WMDs by effect—requiring that a weapon be capable of causing mass casualties or destruction, regardless of its type. This distinction is critical: A definition focused on weapon type might encompass fentanyl as a toxic chemical, while a definition focused on effects would ask whether fentanyl is actually being used in a manner capable of mass harm. Furthermore, the statutory definitions of WMD offenses incorporate different knowledge and intent requirements. Some demand specific intent to cause particular harms, while others require only knowing possession or use of prohibited materials. 

The broadest WMD definition appears in the criminal code at 18 U.S.C. § 2332a(c)(2), which prohibits the “use of weapons of mass destruction.” The statute covers four categories: (A) destructive explosive devices like bombs and grenades; (B) using weapons “designed or intended to cause death or serious bodily injury through the release, dissemination, or impact of toxic or poisonous chemicals or their precursors;” (C) biological agents; and (D) radiological weapons. Crucially, this definition has no threshold for the scale of harm. In this way, the statute focuses on the type of weapon, not the magnitude of its effects, though it does require that a weapon is “designed or intended to cause death.” Prosecutors charged Timothy McVeigh with using a WMD under this statute in the Oklahoma City bombing, and courts have applied the same provision to defendants possessing pipe bombs. 

Other statutes take a narrower view. The Defense Against Weapons of Mass Destruction Act (50 U.S.C. § 2302) and Foreign Intelligence Surveillance Act (50 U.S.C. § 1801(p)) both require that a weapon “is intended” or have “the capability to cause death or serious bodily injury to a significant number of people.” These statutes would exclude a small-scale poisoning from the WMD category—a conceptually coherent limitation, though Congress never defined “a significant number”. The statutory framework outlining the Proliferation Security Initiative (50 U.S.C. § 2902(2)) takes yet another approach, defining WMDs simply as “chemical, biological, and nuclear weapons” and their precursor materials, without reference to either scale or intent. 

Most significantly for the executive order, the statute it expressly invokes—10 U.S.C. § 282, authorizing military assistance in “emergency situations involving weapons of mass destruction”—contains no definition of WMDs at all. The term “weapons of mass destruction” appears in the section heading and text but is left entirely undefined. Although the statute also fails to provide any reference to a WMD definition in another portion of the code, it does refer to the prohibition on the “use of weapons of mass destruction” in 18 U.S.C. § 2332a—suggesting that 10 U.S.C. § 282 would adopt the same WMD definitional framework as 18 U.S.C. § 2332a. 

This fragmented landscape reflects Congress’s ad hoc approach to WMDs legislation over several decades. The practical consequence is that the same substance might qualify as a WMD for some statutory purposes but not others—leaving agencies, courts, and prosecutors to puzzle out whether fentanyl fits each statute’s particular criteria.

Does Fentanyl Fit the Statutes?

The executive order’s framing—that fentanyl is “closer to a chemical weapon than a narcotic”—points toward the chemical-weapons prong of the various WMD definitions. The argument has merit. Fentanyl is approximately 100 times more potent than morphine, and its lethal dose is comparable in scale to traditional nerve agents. Carfentanil, a fentanyl analogue, is approximately 10,000 times more potent than morphine and has been characterized by the U.S. Army’s chemical defense experts as a potential chemical warfare agent.

Nor is this a purely theoretical concern. In 2002, Russian forces deployed an aerosolized fentanyl derivative against Chechen terrorists holding hostages in a Moscow theater; the gas incapacitated the attackers but also killed over 110 hostages through respiratory failure. Though this form is not what is currently trafficked, the incident demonstrated that derivatives can be weaponized for mass-casualty attacks. Further, the congressionally mandated Commission on Combating Synthetic Opioid Trafficking assessed in February 2022 that “illicit synthetic opioids have the effect of a slow-motion weapon of mass destruction.”

The most plausible existing statutory hook is 18 U.S.C. § 2332a(c)(2)(B), which covers “any weapon that is designed or intended to cause death or serious bodily injury through the release, dissemination, or impact of toxic or poisonous chemicals, or their precursors.” Fentanyl has previously been considered a type of chemical agent, with a lethal dose comparable to traditional nerve agents banned by the Chemical Weapons Convention. The executive order’s reference to fentanyl’s “core precursor chemicals” maps directly onto the statute’s “precursors” language. And the statute imposes no minimum-casualty threshold—if a pipe bomb qualifies, why not fentanyl?

The statutory text, however, requires more than mere toxicity. It requires a “weapon that is designed or intended to cause death.” This language presents three distinct obstacles. 

First, fentanyl is not designed or sold as a weapon. It is a pharmaceutical developed and commonly prescribed in the United States since 1968 for legitimate medical use as an analgesic (pain reliever). And even illicit fentanyl is manufactured and distributed as a drug—something users intend to consume for its psychoactive effects, not as an instrument of harm against others. The deaths fentanyl causes are predominantly overdoses among users, not attacks by traffickers against victims.

Second, traffickers do not intend to kill their customers. Drug dealers have obvious economic incentives to keep their clientele alive. While they may be reckless or indifferent to the risk of overdose deaths, this falls short of the specific intent to “cause death or serious bodily injury” that § 2332a contemplates. The statute historically has been applied to terrorist plots and attacks, not commercial transactions with tragic consequences.

Third, the “release, dissemination, or impact” language connotes a mode of delivery characteristic of chemical weapons: dispersal into an environment to affect those present, rather than the voluntary consumption model of drug transactions. For example, sarin is “released” into a subway; fentanyl pills are sold to willing buyers.

The definitions requiring harm to a “significant number of people” or a “mass casualty incident” present additional difficulties for qualification under 50 U.S.C. §§ 1801(p) and 2302(1). Granted, the aggregate death toll from fentanyl is staggering, with the Centers for Disease Control and Prevention estimating that synthetic opioids—primarily fentanyl—caused approximately 72,776 overdose deaths in 2023. From 2021 to 2023, synthetic opioids claimed almost a quarter of a million American lives. These numbers dwarf American combat deaths in any war since Vietnam.

But these deaths result from millions of discrete transactions, each involving quantities intended for individual consumption. No single fentanyl sale causes mass casualties in the way a bomb or nerve agent attack would. Handguns contribute to tens of thousands of annual homicides without becoming a WMD; the same logic would seem to apply to individual drug doses.

The counterargument is that large fentanyl shipments, if released or dispersed, could cause mass casualties—and some statutes ask about capability (as is the case with both 50 U.S.C. §§ 1801(p) and 2302(1)), not actual use. One kilogram of fentanyl contains approximately 500,000 lethal doses. Under this reading, large-scale trafficking in fentanyl involves quantities that have “the capability to cause death or serious bodily injury to a significant number of people,” even if that capability is never realized in a single incident.

The Executive Order’s Weight and Effect

So, what effect does President Trump’s executive order have by declaring fentanyl a WMD? The answer depends on what the designation is supposed to accomplish, ultimately raising fundamental separation of powers and statutory interpretation questions.

An executive order cannot amend a statute or create new law. As Justice Hugo Black wrote in Youngstown Sheet & Tube Co. v. Sawyer, “The President’s power to see that the laws are faithfully executed refutes the idea that he is to be a lawmaker.” Thus, an executive order cannot impose new legal obligations without congressional authorization, and it cannot override statutory definitions that Congress has enacted. Rep. Lauren Boebert’s (R-Colo.) introduction of H.R.128 into the House of Representatives this year, seeking to define fentanyl as a WMD for the purposes of the Homeland Security Act, further bolsters this fact.

This means Trump’s executive order cannot make fentanyl a WMD for purposes of criminal prosecution under § 2332a if the statutory definition does not encompass it. Federal prosecutors would still need to prove that fentanyl meets the statutory elements—and defendants could challenge whether the “designed or intended” and “toxic or poisonous chemicals” language extends to drug trafficking. The order does not, and cannot, resolve that interpretive question.

What the executive order can do is direct executive agencies to treat fentanyl as a WMD for purposes of their internal operations, resource allocation, and enforcement priorities. Whether this designation unlocks new statutory authorities depends on whether fentanyl can fit within existing statutory definitions of WMDs, a question that could ultimately end up in court. 

Section 2(a) of the order directs the attorney general to “pursue investigations and prosecutions into fentanyl trafficking, including through criminal charges as appropriate, sentencing enhancements, and sentencing variances.” This is largely hortatory—the attorney general already possesses the authority to prioritize certain prosecutions. The reference to “sentencing enhancements” likely contemplates 21 U.S.C. § 841, which already imposes heightened penalties for fentanyl trafficking resulting in death.

Whether prosecutors will attempt to bring § 2332a charges against traffickers remains to be seen; as discussed above, such prosecutions would face significant legal hurdles. If § 2332a becomes a viable path for prosecutors, the WMD designation could make it easier to prosecute material support to terrorism under 18 U.S.C. § 2339A, which prohibits providing material support knowing or intending it will be used to violate specific statutes, including § 2332a’s prohibition on weapons of mass destruction. By contrast, the designation likely adds little to prosecutions under the material support statute often used in connection with foreign terrorist organizations (FTOs), 18 U.S.C. § 2339B, as drug trafficking that financially supports the designated FTOs likely already constitutes prohibited material support regardless of whether the drugs are classified as WMDs. 

Section 2(b) directs the secretaries of state and treasury to “pursue appropriate actions against relevant assets and financial institutions” involved in fentanyl trafficking. This provision gestures toward Executive Order 12938, which declared a national emergency regarding WMDs proliferation and authorized sanctions by the Office of Foreign Assets Control against foreign persons contributing to WMDs proliferation. If fentanyl qualifies as a WMD, traffickers could potentially be designated under the Weapons of Mass Destruction Proliferators Sanctions Regulations. However, the administration already possesses extensive sanctions authority against drug traffickers under Executive Order 14059, which President Biden issued in 2021, specifically targeting the illicit drug trade. The marginal benefit of WMD-related sanctions authority is unclear.

But the more significant implication may involve asset forfeiture rather than sanctions. The administration already possesses the authority to freeze assets of drug traffickers through Executive Order 14059’s invocation of the IEEPA. However, the IEEPA authorizes only asset freezing—a temporary measure that restricts access to property without transferring ownership to the government. Forfeiture, by contrast, permanently confiscates assets.

Here, the WMD designation could unlock more powerful tools. 18 U.S.C. § 981(a)(1)(G) authorizes civil forfeiture of property “derived from, involved in, or used or intended to be used to commit any Federal crime of terrorism”—and § 2332b(g)(5) defines “Federal crime of terrorism” to include violations of 18 U.S.C. § 832(d)(2) and § 2332a. If prosecutors can establish that fentanyl trafficking constitutes a WMD offense, they could pursue permanent seizure of assets under civil forfeiture procedures, which require only a preponderance of evidence rather than proof beyond a reasonable doubt. This represents a meaningful upgrade over the IEEPA’s freezing authority, though it still depends on courts accepting that fentanyl meets the relevant statutory definition for weapons of mass destruction.

Section 2(c) directs the defense secretary and attorney general to determine whether the threats posed by illicit fentanyl warrant the Department of Defense’s provision of resources to the Justice Department as necessary during a domestic emergency involving a weapon of mass destruction pursuant to 10 U.S.C. § 282. Notably, this could provide a possible pathway around the Posse Comitatus Act and the general prohibition against federal military intervention in domestic law enforcement. 10 U.S.C. § 282 authorizes the federal military to respond to “an emergency situation involving a weapon of mass destruction” and engage in typical law enforcement activities when “the action is considered necessary for the immediate protection of human life” and “civilian law enforcement officials are not capable of taking the action.” By tasking agency officials with incorporating fentanyl into the WMDs emergency response framework, the order potentially opens the door to military involvement targeting drug networks on American soil.

Additionally, following 9/11, the Patriot Act broadened the Department of Defense’s authority to support law enforcement during weapons of mass destruction emergencies. Under 18 U.S.C. § 2332e, the attorney general may independently request assistance from the Pentagon in responding to WMDs emergencies.

Section 2(d) directs the defense secretary, in consultation with the homeland security secretary, to update all directives regarding the armed forces’ response to chemical incidents in the homeland to include illicit fentanyl. The Pentagon houses a joint service chemical and biological rapid response team (CB-RRT) designed to assist local law enforcement in responding to emergencies. Updating their chemical incident response-related directives to include fentanyl could potentially broaden the scenarios in which CB-RRT deploys and any corresponding domestic collaboration between the Department of Defense and the Justice Department.

Section 2(e) directs the secretary of homeland security to “identify threat networks related to fentanyl smuggling using WMD- and nonproliferation-related threat intelligence.” This provision aims to leverage the Department of Homeland Security’s Countering Weapons of Mass Destruction Office (CWMD)—the same office that advocated for this approach in a 2019 memo, noting CWMD could apply its “assets and capabilities to the fentanyl problem through the lens of WMD.” However, the Homeland Security Act of 2002, which established CWMD, contains no explicit provision authorizing its application to fentanyl. This is precisely why Rep. Boebert introduced H.R. 128—to legislatively require CWMD to treat fentanyl as a WMD. Until Congress acts, the office’s authority to redirect WMD-specific resources toward fentanyl interdiction remains legally uncertain.

Other Possible Implications of the Executive Order

In 2018, the executive cited the threat of chemical WMDs to justify the use of force in Syria without congressional approval, relying on its inherent Article II power for airstrikes on Assad regime-controlled facilities “because [it] … would be in the national interest and … the anticipated hostilities would not rise to the level of a war in the constitutional sense.” If the president attempted to use the fentanyl WMD designation to invoke the same theory of inherent Article II power, notwithstanding the fentanyl distributors’ lack of intent to harm, it could potentially serve as a rationale for using force abroad without congressional approval.

Additionally, in the international law context, the administration has argued that the existence of an “armed conflict” with cartels involved in drug distribution justifies the use of military force against alleged drug traffickers. Lethal strikes outside of an “armed conflict” or in the absence of an “armed attack” are illegal under international law, and trafficking drugs into a country does not alone establish an armed attack warranting the right to self-defense.

The order states that cartels “engage in armed conflict over territory and to protect their operations” that goes “beyond the immediate threat of fentanyl itself.” If this alleged “armed conflict” reaches American cities or engages Americans abroad, it could be used in an attempt to further justify the use of military force against cartels. 

Conclusion

This new order leaves many open questions about how fentanyl could fit into the existing WMDs statutory framework and what additional executive authority such a finding would unlock. The practical stakes are significant: expanded prosecutorial tools, enhanced financial forfeiture powers, and possible legal justification for increased federal military intervention in domestic and international affairs. The order tests the boundaries of these authorities and highlights tensions between executive policy priorities and statutory constraints that could produce litigation refining the boundaries of presidential power and the statutory expression of weapons of mass destruction.