Hamas’ attacks and the Israeli bombing campaign in Gaza that followed have rightly drawn critical attention to the applicable international humanitarian law standards governing the conduct of hostilities. As U.S. weapons transfers to Israel increase, and in light of the unparalleled U.S. security assistance and arms sales relationship with Israel, relevant U.S. policies and laws that apply to arms transfers merit similar attention. We hope this guide will assist lawmakers, policymakers, media, civil society, and the interested public.

An Overview of U.S. Military Assistance to Israel 

Israel is the largest cumulative recipient of U.S. military assistance since World War II, amounting to over $124 billion, not adjusted for inflation. U.S. aid to Israel is outlined in a unique 10-year memorandum of understanding (MOU) that pledges the United States will provide billions of dollars of military aid per year, years in advance. The most recent MOU was signed in 2016 and pledged $38 billion through 2028. While the MOU is not legally binding, Congress has consistently endorsed and abided by the arrangements, including through affirming legislation.

The majority of U.S. assistance to Israel is provided through Foreign Military Financing (FMF), which are grants that allow recipients to purchase U.S. defense articles and services. U.S. FMF alone represents approximately 16 percent of Israel’s defense budget. The government of Israel is also uniquely permitted to use FMF funding to develop and purchase arms from its own domestic industry, called offshore procurement. For Fiscal Year 2023, Israel was allowed to use $775 million of the $3.3 billion in FMF for offshore procurement. While this practice is being phased out under the current MOU, it has historically infused billions of U.S. dollars into Israel’s domestic defense industry.

Israel receives its FMF in a lump sum within 30 days of the funds being appropriated. The funds are held in a U.S. interest-bearing bank account, allowing the government of Israel, rather than U.S. taxpayers, to benefit from the interest gained. Israel is also one of a few countries permitted to use FMF to buy U.S. weapons directly from U.S. arms manufacturers through the Direct Commercial Sales (DSC) process rather than the normal government-to-government Foreign Military Sales (FMS) process. Unlike government-to-government sales, congressional notifications for proposed DCS packages are not made public and are seen by only a small handful of legislators and their aides. Moreover, post-transfer reporting on DCS is increasingly opaque, with highly aggregated data that provides only U.S. munitions list category (i.e. groups of articles, services, and technologies the export of which is governed by the International Traffic in Arms Regulations) totals for the previous fiscal year.

Conventional Arms Transfer Policy

The Biden administration issued a Conventional Arms Transfer (CAT) policy in February 2023 to guide the United States’ arms export decisions. Most of the CAT policy focuses on lists of considerations and objectives for arms exports. However, one section of the policy commits to a clear red line: the United States will not transfer weapons when it is “more likely than not” that those weapons will be used to commit, facilitate the commission of, or aggravate the risk of specified violations. Those violations include “grave breaches of the Geneva Conventions of 1949, including attacks intentionally directed against civilian objects or civilians protected as such,” and “other serious violations of international humanitarian or human rights law.” The Biden administration received praise for strengthening the standard relative to the Obama and Trump policies, but experts and some members of Congress emphasized that the true impact of the provision would depend on its implementation.

When it comes to current arms transfers to Israel, the implementation of the “more likely than not” standard deserves scrutiny. Josh Paul, who served as the chief liaison between the State Department’s political-military affairs bureau to Congress and the public, resigned in protest of U.S. arms transfers to Israel and insisted in a PBS interview that the United States is “certainly not acting within the Conventional Arms Transfer policy.”

The Biden administration is supposed to faithfully apply the CAT Policy for all recipients of U.S. weapons – including Israel. Amid growing evidence of possible violations of international humanitarian law during the current war in Gaza, the CAT Policy requires the administration to assess whether its current arms transfers to Israel are “more likely than not” to facilitate future IHL or human rights violations. Congress could also exercise oversight of the administration’s implementation of the CAT policy to ensure it is applied properly and universally.

Aside: Because a future administration could revoke the Biden administration’s CAT policy, we have recommended that Congress consider enshrining the CAT policy requirements in legislation to more consistently guide future administrations.

Weapons Tracking Programs: End-Use Monitoring and the Civilian Harm Incident Response Guidance

U.S. law requires the government to monitor U.S. weapons transferred to other countries to ensure compliance with the agreed terms surrounding their use, custodianship, and physical security. In practice, end-use monitoring programs are focused almost exclusively on protecting U.S. technology and preventing weapons from being transferred to third parties. These programs do not track whether U.S. weapons are used to harm civilians or violate international law.

Following congressional pressure around the Saudi-led coalition’s use of U.S. weapons in a manner that harmed civilians in Yemen, the State Department developed the Civilian Harm Incident Response Guidance (CHIRG). The Washington Post reported that the Guidance, issued in August, outlined a framework “under which officials will investigate reports of civilian harm by partner governments suspected of using U.S. weapons and recommend actions that could include suspension of arms sales.”

The war in Gaza presents one of the first major tests of the new guidance. Many weapons that Israel has used in Gaza thus far are likely from the United States. However, the details of CHIRG implementation remain obscure – in fact, the former State Department official referenced above, Josh Paul, wrote that a planned publication on the CHIRG was canceled because “the department was so adamant to avoid any debate” on civilian harm risks in Gaza from U.S. weapons transfers to Israel.

Political Declaration on Explosive Weapons in Populated Areas

When explosive weapons are used in populated areas, on average, 90 percent of victims are civilians, according to the United Nations. In November 2022, the United States joined 82 other states in endorsing the Political Declaration on Strengthening the Protection of Civilians from the Humanitarian Consequences Arising from the Use of Explosive Weapons in Populated Areas (EWIPA). Israel has not endorsed the Declaration. Although the Declaration is not legally binding, it does represent a high-level commitment from the United States to implement policies designed to avoid and address civilian harm from the use of explosive weapons in populated areas. The Declaration also commits signatories to actively promote the Declaration, pursue its adoption and implementation by additional states, and seek adherence to its commitments by all parties to armed conflict.

Much of the harm to civilians in Gaza thus far appears to derive from the Israeli military’s use of explosive weapons in densely populated urban areas. Despite the United States’ commitments around EWIPA, the United States has continued transferring explosive weapons to Israel without any conditions around their use, according to repeated official statements including from Vice President Harris, Secretary of Defense Lloyd Austin, Pentagon Spokesperson John Kirby, and Deputy Pentagon Press Secretary Sabrina Singh. The International Network on Explosive Weapons raised concerns around the Israeli military’s use of explosive weapons in Gaza in an open letter to the Declaration’s endorsing states. A recent report from Oxfam specifically recommends halting the transfer of 155mm artillery shells, concluding that “Israel’s use of this munition in past conflicts demonstrates that its use [in Gaza] would be virtually assured to be indiscriminate, unlawful, and devastating to civilians.”

Civilian Harm Mitigation and Response Action Plan

In January 2022, Defense Secretary Austin released the Civilian Harm Mitigation and Response Action Plan (CHMR-AP), which marked an unprecedented commitment to overhaul the Department of Defense’s approach to civilian harm from U.S. and partner military operations. Objective 9 of the CHMR-AP focuses on addressing the risks of civilian harm in security cooperation relationships, such as the U.S.-Israel relationship.

Senior-level statements from the Department of Defense in recent weeks have struck a stark contrast with Secretary Austin’s commitments in the CHMR-AP and his prioritization of overhauling the U.S. approach to civilian harm. To maintain the credibility of CHMR-AP efforts, the Department should ensure that CHMR-AP commitments are applied to all partners and are informing ongoing, interagency considerations and evaluations of U.S. security assistance to Israel as well as other countries.

Leahy Law

The twenty-six-year-old Leahy Law, among the most important laws regarding military aid and human rights, bars the United States from providing assistance to foreign military units that have committed gross violations of human rights such as torture, enforced disappearances, extrajudicial killing, or rape. Under this law, the State Department vets recipients of U.S. security assistance and prohibits assistance to any foreign military units when there is credible evidence that the unit has committed a gross human rights violation. But over the years, it has been poorly enforced for U.S. military aid to Israel.

Several factors have historically limited the application of the Leahy Law to Israeli units. Most assistance to Israel has historically not been subject to vetting due to a longstanding loophole, which allowed assistance to be provided without unit vetting if the State Department determined it could not identify the end-user unit at the time of transfer – the case for the majority of U.S. assistance provided to Israel. Due to a recent change in the law and under the terms of a congressionally mandated 2021 agreement with Israel, the State Department should be providing Israel with a list of units ineligible to receive U.S. military aid, if any. (For an in-depth discussion of the Leahy Law’s application to Israel, see Sarah Harrison and Mairav Zonszein’s previous analysis for Just Security.)

In interviews following his resignation, Josh Paul revealed that State Department officials responsible for Leahy Law vetting had, in fact, expressed concern that Israeli units had potentially engaged in gross human rights violations, but the State Department has been unable to actually “come to a conclusion, which requires senior-level sign-off.” Paul reports that he repeatedly brought concerns to senior State Department officials, but his concerns were never addressed. He described the Leahy vetting process for Israel as a “broken system.” Public releases indicate that no Israeli unit has ever been listed as prohibited under the Leahy Law.

The State Department could find the Leahy Law inapplicable to some potential violations in Gaza because the U.S. government requires that, for wartime conduct, gross violations of human rights must also be violations of international humanitarian law to trigger the Leahy Law’s restriction, and U.S. government officials have stated on several occasions that the U.S. government is not currently evaluating Israeli compliance with IHL. Ongoing and escalating abuses in the West Bank could more easily trigger Leahy Law restrictions.

The Leahy Law can be a powerful tool to ensure U.S. security assistance is not supporting violations of international law. Failures to properly implement the law have rendered it an unlikely tool for meaningful oversight when it comes to U.S. aid to Israel.

Section 502B of the Foreign Assistance Act

Section 502B of the Foreign Assistance Act includes both a prohibition on security assistance to countries where the government engages in a “consistent pattern of gross violations of internationally recognized human rights” and a process for Congress to require a State Department report on human rights conditions and possibly restrict security assistance to the country in question.

Congress could use the process laid out in Section 502B(c) to scrutinize the Biden administration’s approach to arms transfers to Israel. Under Section 502B(c), either chamber of Congress can pass a simple resolution, privileged in the Senate, to require a State Department report on a country’s human rights practices. The State Department must provide the requested report within thirty days – if it does not, no security assistance, including arms sales, may be delivered until the report is provided. Upon receiving the report, any member of Congress may introduce a joint resolution of disapproval to continue, condition, restrict, or terminate further security assistance. Congress last required a report under Section 502B(c) in 1976 and used methods outside of the section’s joint resolution process to restrict security assistance to at least one country covered in the report. Representative Bowman (D-N.Y.) included a Section 502B(c) request in a proposed amendment to the House of Representatives’ Israel appropriations supplemental that the House passed on November 2 and that remains under consideration in the Senate.

Arms Export Control Act Joint Resolutions of Disapproval

The Arms Export Control Act (AECA) requires the State Department to notify Congress of certain major arms sales, at which point Congress has the opportunity to block the sale in question if it can enact a joint resolution of disapproval within a specified timeframe. Congress has never successfully done so for any country, due in part to the need to overcome a likely presidential veto. For Israel, which along with NATO and other “major non-NATO allies” enjoys a special status in the AECA, the dollar threshold for notification can be as high as $100 million and with a truncated window for congressional action of just 15 days.

Due to peculiarities around how the United States is supplying Israel with arms, the State Department has not publicly notified Congress of any new arms sales to Israel since October 7, although it has reportedly transmitted private notifications. Some weapons transfers to Israel have come from the War Reserves Stock Allies – Israel (WRSA-I), which is not subject to the waiting period and joint resolution of disapproval laid out in the AECA. Some weapons transferred since October 7 were subject to notification in 2021, when Senator Sanders and Representative Ocasio-Cortez introduced companion joint resolutions of disapproval that did not receive floor votes. Still other transfers may be taking place below the notification threshold, meaning they occur out of the public eye and without official notification to Congress. In the absence of notifications, members of Congress can demand transparency regarding the weapons the United States is providing to Israel. Where new transfers are notified to Congress, and where Congress has concerns about the high risks of civilian harm from such weapons transfers, the AECA’s privileged procedures provide a tool to force a debate and vote on the Senate floor.

Notably, the White House’s supplemental request – a $100-billion package covering military aid to both Ukraine and Israel – would create a waiver to exempt assistance to Israel from congressional notification and review. Specifically, the waiver is attached to the administration’s request for an additional $3.5 billion in FMF to Israel. While the funds in the package would be available until September 30, 2025, there is no time limitation on the waiver. The House’s Israel-only version of the supplemental includes this notification waiver. As a matter of congressional oversight and transparency, the authors strongly oppose the inclusion of such a waiver, for Israel or any other country.

IMAGE: US President Joe Biden (L) listens to Israel’s Prime Minister Benjamin Netanyahu as he joins a meeting of the Israeli war cabinet in Tel Aviv on October 18, 2023, amid the ongoing battles between Israel and the Palestinian group Hamas. (Photo by BRENDAN SMIALOWSKI/AFP via Getty Images)