The Law of Gravity: A Newtonian Proposal for Public International Law

[Rachel López is an associate professor of law at Drexel University’s Kline School of Law and a fellow at the Carr Center for Human Rights Policy at Harvard Kennedy School. She is also a former Fulbright Scholar and fellow at the Schell Center for International Human Rights at Yale Law School.]

Gravity is a concept that is frequently invoked in international spaces, but seldom defined. By way of example, torture by U.S. Soldiers in Afghanistan, requiring employers to provide insurance that covers contraception, and the death penalty have all been described as grave violations of international law. Gravity is a central feature of public international law across international criminal law, international human rights law, and international humanitarian law. It is referenced in treaties, judgments by international and regional bodies, human rights reports, and the resolutions of the United Nations. These documents often refer to violations of international law, interchangeably, as “gross,” “serious,” and “grave.”  Yet, what makes a violation particularly grave is often unclear. Is it the extreme harm to the victim, the type of rights involved, who committed the violation, or rather the intent of the wrongdoer? My most recent law review article, The Law of Gravity (forthcoming in the Columbia Journal of Transnational Law), aims to bring more grounding to this concept by conducting a near exhaustive analysis of the circumstances that make violations of international law grave.

Skeptics might question why I would devote so much time and effort to defining concept so ingrained in our lexicon that its use sometimes feels intuitive. In part, my interest was sparked by the realization that gravity drives so much in the international sphere. Its effects are more than simply rhetorical. Classifying a violation as grave has significant legal consequences under international law. At times, gravity operates as a filter, determining whether international courts have jurisdiction to prosecute a crime or when treaty monitoring bodies can take up an issue. Gravity can also limit State action. For example, under the Arms Trade Treaty (ATT), States are prohibited from selling arms to other States if they commit grave violations of human rights or humanitarian law. Alternatively, gravity has also been used to justify military intervention or punishing a State more harshly for its wrongful acts. In this way, gravity acts as counterweight to sovereignty.

At the same time, gravity as a legal concept is underexplained and undertheorized. Grave violations have become the “I know it when I see it” of international law. Studies show that most people think that they can identify “the worst of the worst” violations. We all assume our deeply held beliefs about fundamental questions of right and wrong are shared by everyone else. But, as the above examples show, our beliefs are based on social constructs that are in turn shaped by cultural norms. They depend on our nationality, race, class, political orientation, and gender—to name a few.

International actors are no different. Unconstrained by law, they are equally inept at controlling their biases, particularly if laced with political motives. Since the gravity of a violation can justify international intervention into otherwise sovereign matters, the risk of manipulation is heightened. And so are the costs to the legitimacy. Indeed, gravity has become an Achilles hell for some international institutions, exposing them to allegations that they are using gravity determinations to shield powerful states from accountability for atrocious acts. Thanks to the compelling work of Margaret deGuzman who just released a new book on the subject, the most well-known example is the International Criminal Court (ICC).  There, the dismissal of a number of high-profile cases involving powerful States like the United States, the United Kingdom, and Israel on the basis of gravity raised concerns about bias and threatened the ICC’s legitimacy. A perhaps lesser known example is the UN Commission on Human Rights, the precursor to the UN Human Rights Council. This Commission could only investigate human rights abuses when there was “a consistent pattern of gross and reliably attested violations of human rights and fundamental freedoms.” Over time, it developed a reputation for basing its investigative decisions on political concerns rather than legal criteria, thereby failing to address to the gravest violations of human rights across the globe. 

The central goal of my research is to reify gravity, hoping that doing so will constrain biases and reduce the legitimacy deficit in public international law. By examining all the primary sources, ranging from treaties to decisions by international courts, that grapple with gravity across international criminal law, human rights law, and international humanitarian law, I identified a common set of considerations that denote gravity. Namely, violations are typically deemed grave, when all of the following primary determinants are present:

(1) they are universally condemned as grave,

(2) done deliberately, and

(3) either acutely harm a limited number of individuals or are so widespread and systematic that the cumulative harm is severe.

So, while the extrajudicial killing of journalist Jamal Ahmad Khashoggi is a grave violation of international law, so is the pillage of villages in South Sudan.

What is the legal significance of these primary determinants? I contend that their presence triggers obligations erga omnes. These are duties owed “to the international community as a whole,” because they involve issues that concern all States, such as the maintenance of peace and security. Due to their importance, all States have a legal interest in their protection. However, since the International Court of Justice (ICJ) invoked them in Barcelona Traction in 1970, what implicates erga omnes obligations has been murky. While these obligations are often tied to violations of jus cogens, or preemptory norms, as other scholars have concluded, they are broader. In the Bosnian Genocide Case, for instance, the ICJ noted an additional category that trigger these duties: violations of norms “which protect essential humanitarian values.”  

Gravity illuminates the full scope of erga omnes obligations, above and beyond violations of jus cogens norms. Like erga omnes obligations, grave violations are often said to concern all States. Just a few examples: The Charter for the Nuremberg Tribunal identified war crimes, crimes against humanity, and crimes against peace, as being “so grave as to concern the international community as a whole.” Similarly, the Rome Statute provides the International Criminal Court with “jurisdiction over the most serious crimes of concern to the international community as a whole.” This also subtly links to the first of the primary determinants: When the international community universally condemns a violation as grave, then, by its nature, the violation concerns to all States. There is also a salient link between obligations erga omnes and the second determinant. Namely, in Barcelona Traction, the ICJ found that certain violations of “the basic rights of the human person” conjure erga omnes obligations. When violations cause harm that is either particularly acute for a limited number of people or so widespread that the cumulative harm is severe, “the basic rights of the human person” are infringed. Consequently, such violations conjure obligations erga omnes.

Not buying my argument yet, consider this: the duties of States following a grave violation of international law (as articulated by the International Law Commission) are the mirror image of obligations erga omnes (as articulated by the International Court of Justice). More precisely, in both cases, all States have a duty of abstention, which is comprised of two obligations. First, States cannot recognize the situation resulting from the breach. Second, they cannot render aid or assistance in maintaining that situation. All States must also to cooperate in bringing an end to the violation.

In addition to the aforementioned primary determinants, there are also a set of aggravating factors. Specifically, a grave violation is considered worse when it:

1. involves an abuse of authority, particularly by State actors
2. injures populations that are particularly vulnerable, like children, or
3. occurs over an extended period of time. 

While these factors are not uniformly required, when present, they increase the gravity of a violation of international law and therefore merit harsher consequences. In other words, once the first gravity threshold is met, these aggravating factors determine what actions can be taken to correct a violation of international law as well as the level of intensity of those corrective actions. This is in line with the well-established principle that any countermeasures undertaken to ensure compliance with international law must be proportionate to the degree of the breach.

Still this analysis begs the question, does public international law need universal criteria across all these legal regimes? If the problem is legal certainty, couldn’t we get there by simply concretizing gravity criteria in each regime? Such questions to my mind lose sight of the common purpose of all three legal regimes: to prevent human beings from suffering harm caused by acts considered to be the worst of the worst across the globe. Whether it entails prosecuting a war criminal or economic sanctions aimed at a State, the goal is the same, nonetheless. In my view, the divergence across the various enforcement bodies should be a question of degree of punishment, rather than the need for varying definitions of gravity across the different arenas of public international law.

Admittedly, the malleability of gravity can be useful when dealing across contexts that vary significantly, but the costs of this ambiguity are too high. As I have outlined here, the lack of transparency about what constitutes a grave violation has thrown into question the credibility of international institutions meant to punish those acts considered to be the worst of the worst.  The fragmentation of public international law has further aggravated the international community’s efforts to consistently punish grave violations. The elucidation of and stricter adherence to the concrete gravity considerations laid out here will permit international law not only to escape from the rigidity of hard definitions of gravity, but also to benefit from more consistency across legal regimes. As these legal regimes become increasingly interconnected, more dependable and transparent understandings of the gravity will result in more uniform and cohesive accountability for those violations that are of most concern to humankind. A law of gravity is required to fully realize such high aspirations.