

 
 Legal Sidebari 
 
Arms Transfers and International Law 
July 29, 2024 
The ongoing conflicts between Russia and Ukraine and between Israel and Hamas have prompted 
questions about the international legal obligations of states that provide arms to parties to a conflict. 
Several cases, for example, have been brought in international and domestic courts (including one in a 
U.S. district court) alleging that countries’ provision of arms to Israel since it launched its military 
campaign in Gaza in response to the October 7, 2023, Hamas terrorist attack violates those countries’ 
obligations under the Convention on the Prevention and Punishment of the Crime of Genocide (Genocide 
Convention) and the Geneva Conventions. The questions raised about the extent to which these 
international law obligations apply to arms transfers may be of interest to Congress because of its roles in 
determining whether and how the United States implements its international legal obligations and in 
authorizing, restricting, and overseeing executive branch decisions regarding the provision of U.S. arms 
to foreign states. This Legal Sidebar (1) discusses the obligations under the Genocide and Geneva 
Conventions that may be relevant to arms transfers, (2) explicates the extent to which these obligations 
are incorporated into the U.S. legal and policy framework governing the process of providing U.S. 
weapons to foreign states, and (3) highlights some issues raised by the foregoing of relevance for 
Congress in light of its legislative and oversight authorities regarding the provision of U.S. weapons to 
foreign states.  
International Law Obligations and Arms Transfers: The 
Geneva and Genocide Conventions 
International humanitarian law (IHL) is the body of treaties and customary international law that govern 
states’ conduct during armed conflicts. The four Geneva Conventions, which are among the major 
components of IHL, provide various protections for civilians and others not actively participating in 
hostilities. The United States is a party to all four Geneva Conventions. The Conventions direct parties to 
criminalize certain violations of Convention requirements listed as “grave breaches.” Congress 
implemented this obligation through the War Crimes Act of 1996 (codified as amended at 18 U.S.C. 
§ 2441). The Act also criminalizes additional IHL violations that may be applicable both to conflicts 
between states and to conflicts involving both state and non-state actors. 
Common Article 1 of the four Geneva Conventions obligates states parties “to respect and to ensure 
respect for the present Convention in all circumstances.” Recent conflicts have prompted questions 
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among commentators about how common Article 1 obligations apply to states that are not parties to an 
armed conflict, particularly those third-party states that are providing arms to states that are engaged in 
the conflict. More specifically, questions have arisen as to the extent to which states are obligated to 
assess whether there is a risk that the arms will be used in violation of the Conventions and, if so, whether 
states are obligated to refrain from or otherwise restrict transfers. The International Committee of the Red 
Cross, for example, has taken the position that Common Article 1’s obligation to “ensure respect” for the 
Conventions requires that “arms-transferring State[s] . . . assess whether the recipient is likely to use the 
weapons to commit IHL violations,” and, “[i]f there is an expectation that this will happen, based on facts 
or knowledge of past patterns . . . refrain from transferring the weapons.”  
While the Geneva Conventions apply only in the context of armed conflict, the Genocide Convention’s 
obligations apply at all times. The Genocide Convention defines genocide as the committing of certain 
acts “with intent to destroy, in whole or in part, a national, ethnical, racial or religious group, as such,” 
including killing members of or causing serious bodily or mental harm to members of the group and 
deliberately inflicting on the group conditions of life calculated to bring about its physical destruction in 
whole or in part. The United States ratified the Genocide Convention in 1988, and Congress passed 
legislation implementing the treaty’s requirements to criminalize genocide offenses that same year. 
Codified in 18 U.S.C. § 1091, the Genocide Convention Implementation Act draws on the language of the 
Convention to criminalize genocide by reference to the two essential elements of genocide under the 
Convention—a specific mental state and an act.  
In addition to prohibiting the commission of genocide, the Genocide Convention prohibits complicity in 
genocide and requires states “to prevent” genocide. The International Court of Justice (ICJ) has held that 
a “State’s obligation to prevent, and the corresponding duty to act, arise at the instant that the State learns 
of, or should normally have learned of, the existence of a serious risk that genocide will be committed” 
(emphasis added). Once a state knows or should know of a serious risk that genocide will be committed, 
its duty to prevent it requires that, if a state “has available to it means likely to have a deterrent effect on” 
the suspected potential offender, “it is under a duty to make such use of these means as the circumstances 
permit.” 
A recent case brought before the ICJ could eventually lead that tribunal to issue an opinion addressing 
states’ obligations under the Genocide and Geneva Conventions when providing arms to other states. In 
April 2024, Nicaragua filed a case against Germany alleging that Germany’s provision of arms to Israel 
for use in its military campaign in Gaza violated the Genocide Convention and IHL as codified in the 
Geneva Conventions. In support of its allegations, Nicaragua argued that Germany “continues to provide 
political, financial and military support to Israel with full knowledge of the ongoing plausible commission 
by Israel of serious breaches of international law facilitated by that support.” In response, Germany 
argued that it had a “robust legal framework that assesses export licensing requests on a case-by-case 
basis, and that ensures compliance with . . . Germany’s international obligations.” Germany further 
maintained that its provision of “war weapons” to Israel had decreased since Israel began its military 
operations in Gaza on October 7.  
The ICJ denied Nicaragua’s request for a preliminary order requiring Germany to stop transferring 
weapons, observing that, before exporting weapons, the German government conducts “an assessment . . . 
to ascertain whether there is a clear risk that the particular item . . . would be used in the commission of 
genocide, crimes against humanity or grave breaches of the four Geneva Conventions,” and that “there 
has been a significant decrease since November 2023 in the value of material for which . . . licences were 
granted” to Israel. The ICJ further stated that it “considers it particularly important to remind all States of 
their international obligations relating to the transfer of arms to parties to an armed conflict, in order to 
avoid the risk that such arms might be used to violate the [Genocide or Geneva] Conventions.” The case 
remains pending on the ICJ’s docket. 
  
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The ICJ’s decisions are binding only on the parties to a given case, and thus in that sense Nicaragua v. 
Germany does not have direct implications for the United States. The ICJ’s decisions are, however, 
considered to be highly authoritative and thus can contribute to the interpretation and development of 
international law. The ICJ’s decisions in Nicaragua v. Germany thus may impact the United States in the 
sense that they may provide the ICJ’s interpretation of international legal obligations that are binding on 
the United States as a party to the Genocide and Geneva Conventions and as a matter of customary 
international law. 
The U.S. Legal Framework Governing the Provision of 
U.S. Arms to Foreign States 
The U.S. domestic statutes governing arms transfers provide the executive branch with broad discretion in 
making arms-transfer decisions and do not explicitly require consideration of whether recipient countries 
are or may be in violation of IHL or genocide prohibitions. The two principal statutes governing the 
executive branch’s provision of arms to foreign states are the Arms Export Control Act (AECA) and part 
of the Foreign Assistance Act (FAA). The AECA provides the President with broad authority to exercise 
discretion in making decisions about U.S. arms exports within the general guidelines specified in the Act. 
Although some of those guidelines arguably address human-rights-related concerns, none include 
consideration of recipient countries’ compliance with international law. The FAA does, however, restrict 
the arms-provision authorities granted to the President in the AECA by prohibiting the provision of 
weapons to “any country the government of which engages in a consistent pattern of gross violations of 
internationally recognized human rights” (Subsection 502(a), codified at 22 U.S.C. § 2304(a)). This 
prohibition is qualified by permitting the President to waive it by providing Congress with a certification 
“that extraordinary circumstances exist warranting provision of such assistance.” 
Both the AECA and the FAA also establish mechanisms for facilitating congressional oversight of the 
executive branch’s implementation of these statutory arms-provision authorities and restrictions in the 
form of notification and reporting requirements coupled with expedited procedures for congressional 
actions. The AECA requires the President to notify Congress of proposed weapons sales above certain 
values and establishes expedited procedures for congressional consideration of joint resolutions 
prohibiting a given proposed arms sale before the time at which the President is authorized to go forward 
with the transaction after notification (15 days for NATO and major non-NATO allies and 30 days for all 
other countries).  
The FAA’s mechanisms for enforcing its prohibition of arms transfers to countries that are in gross 
violation of international human rights law include a requirement that the Secretary of State submit an 
annual report to Congress on the human rights compliance of countries proposed as recipients of U.S. 
security assistance, which “shall include [any] information regarding the commission of war crimes, 
crimes against humanity, and evidence of acts that may constitute genocide” (in Subsection 502B(b) of 
the FAA, found at 22 U.S.C. § 2304(b)). Additionally, Subsection 502B(c) provides for more targeted 
reporting by requiring the Secretary of State to submit a report on a specific recipient country’s 
international human rights compliance if directed to do so by a simple resolution of either house or by 
request from the House Foreign Affairs Committee (HFAC) or Senate Foreign Relations Committee 
(SFRC), and prohibits delivery of the security assistance until the Secretary submits the report. President 
George H.W. Bush claimed that this provision is unconstitutional in light of INS v. Chadha, a 1983 
Supreme Court decision invalidating a statutory provision in an unrelated statute that allowed one 
chamber to invalidate an agency’s action by majority vote on the ground that it was “legislative in its 
character and effect,” and thus subject to the bicameralism and presentment requirements of Article I. 
Some commentators have maintained, however, that Subsection 502B(c) is not impacted by Chadha 
because the statute’s prohibition of arms sales is automatically triggered by the failure of the Secretary to 
  
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submit a report, rather than any specific action by one chamber or committee. Notwithstanding any 
disagreement about Chadha’s applicability, however, the circumstances where such a dispute would be 
justiciable are unclear. Finally, Subsection 502B(c) also establishes expedited procedures for 
congressional consideration both of a simple resolution requiring the report and of a joint resolution 
terminating, restricting, or continuing assistance after a report is submitted.  
Although the FAA requires that annual recipient country human-rights reports include information on the 
commission of war crimes and genocide, there are no explicit prohibitions or other restrictions in the FAA 
related to the provision of U.S. arms to foreign states that are or may be committing war crimes in 
violation of the Geneva Conventions or that are or may be perpetrating genocide or crimes against 
humanity. Accordingly, current law grants the executive branch broad discretion in determining whether 
to consider actual or potential violations of the Geneva and Genocide Conventions in making arms-
transfer decisions and, if it does consider such violations, how much weight to give them. The Biden 
Administration has, to some extent, incorporated such considerations into its nonbinding policy-guidance 
documents, which a subsequent administration would be free to revoke or otherwise change to reflect its 
policy priorities. 
Congressional Considerations 
Like many treaties, the Geneva and Genocide Conventions require parties to enact legislation to fulfill 
certain obligations. As a matter of U.S. law, the Supreme Court has recognized that Congress may pass 
legislation implementing U.S. treaty obligations as well as legislation that modifies or is contrary to those 
obligations, which if enacted would be the governing domestic law even if in conflict with the treaty 
(although another treaty party may have a valid claim under international law in the event that the United 
States breached its treaty obligations). As noted, Congress has implemented U.S. obligations under the 
Geneva and Genocide Conventions to criminalize certain violations of their prohibitions. In determining 
whether and how to exercise its legislative and oversight authorities in relation to the executive branch’s 
decisions about the provision of arms and any relevant U.S. obligations under international law, including 
under the Geneva and Genocide Conventions, Congress could consider, for example, 
•  restricting or broadening the executive’s branch’s discretion to provide arms to countries 
that are or are likely engaging in violations of international law, including by explicitly 
including or excluding bodies of international law such as IHL or obligations related to 
genocide (as some recent bills would do), or by removing, limiting, or expanding the 
President’s waiver authority;  
•  adding or removing reporting requirements on recipient countries’ compliance with 
international law;  
•  amending Subsection 502B(c) of the FAA to also provide expedited procedures for 
consideration of a joint resolution requiring a targeted report and prohibiting arms 
transfers until it is submitted and/or for a joint resolution terminating, restricting, or 
continuing assistance to a country if the Secretary of State does not provide a requested 
report in light of the constitutional questions raised by Chadha; or 
•  by engaging in further oversight of the executive branch implementation of arms-
provision laws. 
 
  
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Author Information 
 
Karen Sokol 
   
Legislative Attorney 
 
 
 
 
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