Michael R. Tregle, Jr. is a U.S. Army judge advocate officer currently assigned as the Brigade Judge Advocate for the 101st Airborne Division Artillery (DIVARTY). A former enlisted infantryman, he has served at almost every level of command, from the infantry squad to an Army Service Component Command, and overseas in Afghanistan and the Pacific Theater. He tweets @shockandlawblog and writes at www.medium.com/@shock_and_law. Divergent Options’ content does not contain information of an official nature nor does the content represent the official position of any government, any organization, or any group.
National Security Situation: On January 31, 2017, the United Nations (U.N.) Panel of Experts on Yemen issued a report concluding that widespread violations of International Humanitarian Law (IHL) had occurred in the Yemeni armed conflict. Noting numerous violations throughout 2016 alone, including targeting civilian persons and objects, excessive collateral damage, deprivation of liberty, and torture, the Panel concluded that some of these violations amounted to war crimes. The U.S. provided billions of dollars in logistical support, munitions, and intelligence sharing to the Saudi-led coalition that was responsible for the IHL violations. Such support could render the United States liable for Saudi violations under the law of state responsibility or as an aider and abettor.
Date Originally Written: May 19, 2017.
Date Originally Published: June 29, 2017.
Author and / or Article Point of View: The author is an active duty officer in the U.S. Army. This article is written from the point of view of the United States toward continued support of the Saudi-led coalition in the Yemeni war in light of war crimes allegations made by the U.N. Panel of Experts on Yemen.
Background: Until October 2016, U.S. support to the Saudi-led coalition fighting Houthi rebels in Yemen included the provision of munitions, including weapons and precision guidance kits, refueling capability, and other logistical support. Following a coalition attack on a funeral in Sana’a that killed 132 civilians and injured nearly 700, which was carried out with a U.S.-supplied GBU-12 precision guided bomb, the United States denounced the attack and suspended further arms sales to Saudi Arabia. The Trump Administration recently announced the resumption of over $100 billion in arms sales to the Saudis, much of which is likely to be used in Yemen. More recently, another key coalition ally, the United Arab Emirates (UAE), was accused of detainee abuse and disappearances, though the link between U.S. support and these accusations is less clear.
Significance: Once the U.S. became aware of the violations, continued support to a Saudi coalition responsible for war crimes could render the U.S. vicariously liable for those crimes. The principle of state responsibility renders states legally responsible for the wrongful acts of others when the state aids or assists in the wrongful act and knows of the circumstances making that act wrongful. Similarly, aider and abettor liability could render the U.S. liable if it knew, or should have known, that the aid it provided could result in war crimes. U.S. liability could take many forms, ranging from international condemnation to the indictment of key U.S. arms-sale decision makers in the International Criminal Court as principles to war crimes. If nothing else, continued support of the Saudi-led coalition in light of the U.N. allegations would erode U.S. credibility as an advocate for human rights and the rule of law and empower other states to ignore international norms protecting civilians in conflict.
Option #1: The U.S. ceases all arms sales and other support to the Saudi-led coalition until the coalition demonstrates improved compliance with IHL and greater protection of civilians in Yemen. Such compliance can be ensured through neutral observers, assurances from coalition members, and the provision of U.S. trainers and advisors to improve coalition targeting procedures and detention and interrogation practices.
Risk: This option risks damaging the longstanding security relationship with Saudi Arabia and the UAE, key allies in the region. Furthermore, cutting off all support may well strengthen the Houthi opposition in Yemen and foster still worse humanitarian conditions on the ground. If the U.S. fully absolves itself of supporting the Saudis in Yemen, very little international leverage to compel coalition compliance with IHL will remain, possibly leading to even more violations.
Gain: This option seeks to maintain U.S. credibility as a world leader in protecting the victims of conflict and demonstrates a willingness to hold even its closest friends accountable for violations. It further ensures that the U.S. will not be complicit in any way in continued war crimes or other IHL violations in Yemen, thereby avoiding international condemnation or legal liability.
Option #2: The U.S. continues arms sales and logistical support to the Saudi-led coalition regardless of its compliance with international law. This option represents maintaining the status quo, and has been implicitly endorsed by the Trump administration.
Risk: As a result of this option, the U.S. will certainly face international condemnation and potential legal liability for supporting a Saudi regime that the U.S. knows is engaged in widespread IHL violations and potential war crimes. At best, the U.S. reputation as a leader in upholding IHL and human rights norms will be damaged. At worst, senior U.S. officials could be indicted as principles to war crimes under theories of state responsibility or aiding and abetting the coalition’s conduct.
Gain: The U.S. cements its relationship with Saudi Arabia as a key ally in the region and makes clear that defeating the Houthi rebellion, and by extension denying Iranian influence in the region, is of greater import than compliance with IHL. This option signals to coalition allies that they have U.S. support in imposing their will on Yemen, whatever the cost.
Other Comments: None.
 International Humanitarian law refers to the international law of war or law of armed conflict. The three terms are synonymous.
 See also Ryan Goodman & Miles Jackson, State Responsibility for Assistance to Foreign Forces (aka How to Assess US-UK Support for Saudi Ops in Yemen), Just Security, Aug. 31, 2016, https://www.justsecurity.org/32628/state-responsibility-assistance-foreign-forces-a-k-a-assess-us-uk-support-saudi-military-ops-yemen/; Ryan Goodman, Jared Kushner, the Arms Deal, and Alleged Saudi War Crimes, Just Security, May 20, 2017, https://www.justsecurity.org/41221/jared-kushner-arms-deal-alleged-saudi-war-crimes/.
 Phil Stewart & Warren Strobel, U.S. to Halt Some Arms Sales to Saudi, Citing Civilian Deaths in Yemen Campaign, Reuters, Dec. 13, 2016, http://www.reuters.com/article/us-usa-saudiarabia-yemen-exclusive-idUSKBN1421UK.
 Jared Malsin, The Big Problem with President Trump’s Record Arms Deal with Saudi Arabia, Time, May 22, 2017, http://time.com/4787797/donald-trump-yemen-saudi-arabia-arms-deal/?xid=homepage.
 Ryan Goodman & Alex Moorehead, UAE, a Key U.S. Partner in Yemen, Implicated in Detainee Abuse, Just Security, May 15, 2017, https://www.justsecurity.org/40978/uae-key-partner-yemen-implicated-detainee-abuse/.
 Aiding and Abetting liability is described in U.S. Dep’t of Def., DoD Law of War Manual para. 18.23.4 (May 2016). For a more detailed explanation, see Ryan Goodman, The Law of Aiding and Abetting (Alleged) War Crimes: How to Assess US and UK Support for Saudi Strikes in Yemen, Just Security, Sep. 1, 2016, https://www.justsecurity.org/32656/law-aiding-abetting-alleged-war-crimes-assess-uk-support-saudi-strikes-yemen/; Ryan Goodman, Jared Kushner, the Arms Deal, and Alleged Saudi War Crimes, Just Security, May 20, 2017, https://www.justsecurity.org/41221/jared-kushner-arms-deal-alleged-saudi-war-crimes/.
 See Malsin, supra note 3.