It is difficult to overstate the importance of the 1949 Geneva Conventions. Nearly synonymous with the law of war itself, the universally ratified 1949 Conventions are not merely a source of elaborate rules of conduct — they are critical and ubiquitous proof of the power of humanitarian interests to persist even during hostilities. Their universality has been a function, however, of their ambiguity. Even at their drafting, consensus required concessions to a vagueness that papered over persistent differences regarding the balance between humanity, military necessity, and sovereignty.

Immediately after they entered force, the Conventions inspired States and delegates present at their drafting to publish supplemental, secondary sources — instructions and commentaries on how to put the Conventions into practice. Yet even these early sources parted ways in significant respects. Some, such as the 1956 US Army Field Manual on the Law of Land Warfare, seemed content with the Conventions’ ambiguities. For the most part, the Field Manual let the Conventions speak for themselves, simply reproducing them verbatim in many cases with minimal elaboration.

Other sources, such as the 1952–1960 Commentaries, produced under the auspices of the ICRC, put a much finer point on the Conventions. In many cases, the authors of the Commentaries viewed it their task to pick up where the Conventions fell short, resolving ambiguities by resort to history, logic, and most often humanitarian impulse. The Commentaries became an occasional source for practitioners, but a frequent one for scholars and jurists not content or not permitted by their analytical responsibilities to allow the Conventions’ ambiguities to stand.

In this way, law of war development involved a decades-long contest for not only what the Conventions said, but more fundamentally, for how best to read them. Whether the Conventions’ silences and ambiguities were bargains to be valued or voids to be filled was a debate that roiled, often unappreciated, beneath many of the most charged battles over the content and meaning of the Conventions.

That interpretive contest continues today in the recently released Updated Commentary on the First Geneva Convention of 1949 and U.S. Department of Defense Law of War Manual. Each publication deserves careful attention for its arguments — explicit and implicit — about how best to read and understand the law of war.

This series of three posts identifies the wide range of interpretive approaches employed by the Updated Commentary, compares them in select instances to those of the new DOD Manual, and offers thoughts on what these new publications and their interpretive choices might signify for law of war development. These posts identify in particular some of the roles that humanitarian logic, operational reality, and sovereignty play in addressing the Convention’s many ambiguities and how each source markets its vision of a more perfect law of war. 

It is first helpful to consider what unites the Updated Commentary and the DOD Manual. Published mere months apart, each replaces an esteemed predecessor that had endured for over 60 years. Although the ICRC disclaimed the Updated Commentary’s predecessor as the personal work of it authors, that 1952 Commentary came to be viewed by many as an authoritative institutional product. So much so that by 2006, the US Supreme Court misidentified it as “the official commentary” on the Conventions.

For better or worse, each publication greatly surpasses the size of its predecessor. The new DOD Manual exceeds the 1956 Field Manual by more than a thousand pages. It is still difficult to evaluate the Updated Commentary in this respect — it is currently unavailable as a single file or printed document. But its commentary on Article 3 alone grew from approximately 9,100 words in the 1952 edition to over 65,000 words in the Updated Commentary (not including a massive bibliography and over 900 footnotes on Article 3 alone).

And finally, the institutional sponsor of each lays an extraordinarily strong claim to comment convincingly on the law of war. In abstract, the qualifications of the US Defense Department to comment authentically on the law of war are exceptional. No State dedicates as many resources to preparing for and conducting armed conflict in accordance with the law of war as does the United States. As the foreword to the 1952 Commentary conceded, “only the participant States are qualified, through consultation between themselves, to give an official and, as it were, authentic interpretation of an intergovernmental treaty.” For its part, the ICRC’s deep field experience facilitating implementation of the Convention and its reputedly vast collection of confidential State practice lend its opinions, especially with respect to suggestions for legal evolution, special relevance.

Still, and as most would expect, the Updated Commentary and the DOD Manual differ in significant respects. To begin, it is important to acknowledge the distinct nature of each publication. The Updated Commentary analyzes a single law of war treaty from a single law of war treaty regime. The DOD Manual is a comprehensive examination of the jus in bello (regulation of the conduct of hostilities) and even includes sporadic treatment of the jus ad bellum (regulation of the resort to hostilities).

Additionally, the two sources differ with respect to authorship. The Updated Commentary is in significant respects a pluralistic product. It was largely assembled by a small team of ICRC legal staff. An Editorial Committee comprised of two ICRC staff members and two scholars with close relationships to the ICRC provided editorial supervision. A diverse Reading Committee — disclosure, I’m a member — carefully reviewed drafts. And a peer-review group of over 60 law of war specialists drawn from 48 States and three non-governmental organizations also reviewed and commented on the entire work.

The DOD Manual is, by comparison, an insular document. Although reportedly reviewed by officials or scholars affiliated with four close US allies, its authorship is well known to have been limited to a small cadre of lawyers in the DOD General Counsel’s Office, and for most of its development, a single lawyer. Interagency review by the US State and Justice Departments purportedly influenced (and delayed) the DOD Manual’s publication as well. Yet neither agency endorses it and in fact the Manual curiously disclaims representing those agencies’, or for that matter, the US Government’s views on the law of war. It should, however, be mentioned that the DOD Manual’s preface solicits outside input (send your recommendations here) and that the Office of General Counsel has attended numerous review events to gather reactions to the manual.

Focused on a single convention, and the First Geneva Convention at that, this first volume of the Updated Commentary enjoys an advantage over the DOD Manual in terms of its narrow and relatively straightforward subject matter. Compared to most law of war subjects, including the Third and Fourth Conventions of 1949 and especially the First Additional Protocol of 1977, the First Convention has not been a source of significant controversy.

All the same, this Updated Commentary proves quite provocative. In particular, its analyses of common Articles 2 and 3 of all four 1949 Conventions warrant careful attention, as each article has recently proved to be a controversial and dynamic provision of the Conventions. A brief examination reveals illustrative gaps between the Updated Commentary and the DOD Manual.

Consistent with the approach of the 1952 Commentary, the Updated Commentary grasps common Article 2 of the Convention as an exceptionally low threshold of application. The Updated Commentary reaffirms that intensity of hostilities forms no part of the determination whether a situation of international armed conflict (known as IAC and commonly understood as a war between two states) exists between State Parties (para. 221). However, with respect to the phenomenon of non-international armed conflicts (known as NIACs and understood to involve conflicts between private armed groups or between such groups and States) that spillover to neighboring States, its conclusion may prove more controversial. Relying on the ICJ’s Armed Activities case, the Updated Commentary asserts in paragraph 261 that:

In some cases, the intervening State may claim that … violence is not directed against the government or the State’s infrastructure but, for instance, only at another Party it is fighting within the framework of a transnational, cross-border or spillover non-international armed conflict. Even in such cases, however, that intervention constitutes an unconsented-to armed intrusion into the territorial State’s sphere of sovereignty, amounting to an international armed conflict within the meaning of common Article 2(1)

The practical consequences of this understanding seem both daunting in the abstract and unlikely to materialize in reality. For instance, it is difficult to imagine States actually instituting the Fourth Convention’s elaborate protected person regime for civilians of supposed enemy nationality in its territory following de minimus cross-border incursions. Even more difficult to envision under such circumstances is implementation of the duties of neutrality attendant to conditions of international armed conflict. Indeed, the Updated Commentary’s succeeding paragraph acknowledges an opposing view (an approach taken frequently throughout).

While it shares the Updated Commentary’s low international armed conflict threshold generally, the DOD Manual discerns from common Article 2 an element of intent in addition to de facto hostilities (paras. 3.4.1 & 3.4.2). That is, a Party must have intended to engage another State Party in hostilities to establish international armed conflict sufficient to activate the Convention. The requirement of intent to engage in hostilities with another State seems to preclude a conclusion that international armed conflict results from situations of mere non-international armed conflict cross-border spillover.

A further significant distinction between the two publications concerns sourcing. The Updated Commentary, especially compared to the DOD Manual, presents an enormously diverse collection of cited works. If it might be said no historical practice (and especially no US practice) is too obscure, dated, or insular for the DOD Manual, it might be said that no private author’s view or tribunal’s decision is too fanciful or outré for the Updated Commentary. It is likely some readers (and States) may find themselves somewhat alienated by instances where the Updated Commentary sides with academic commentary over positions of States. For instance, on both termination of belligerent occupation and applicability of the law of belligerent occupation to non-State territory, the Updated Commentary appears to weigh academic work and an advisory ICJ opinion over positions taken by States (paras. 307–13 & 232–24). Similarly academic authors’ conclusions with respect to armlets marked in miniature worn by auxiliary medical personnel pursuant to Article 41 appear to win out over three States’ military manuals (para. 2629, n. 11).

The Updated Commentary’s treatment of emerging technology also illustrates the great weight accorded to scholarly work. Addressing the question whether cyber operations alone are sufficient to constitute an international armed conflict for purposes of application of the Convention, the Updated Commentary cites the work of four prominent legal scholars. The cited scholars’ work offers cogent analyses concluding that cyber operations’ producing effects analogous to kinetic military operations could amount to international armed conflict. The footnote that supports adoption of these scholars’ work concedes, however, an important contraindication. When convened to address the same questions, a UN Group Governmental Experts could only muster the following:

The application of norms derived from existing international law relevant to the use of [information and communication technologies (ICTs)] by States is an essential measure to reduce risks to international peace, security and stability. Common understandings on how such norms shall apply to State behaviour and the use of ICTs by States requires further study. Given the unique attributes of ICTs, additional norms could be developed over time. (Para. 255, n. 95)

Confronted with the task of generating a consensus statement on the applicability of international law to cyber operations, the collected States said little more than that the issue was unclear to them. That the Governmental Experts’ statement is relegated to a cited contraindication is all the more surprising given that it postdates the scholars’ analyses. The government representatives were seemingly unable at that point to achieve consensus to adopt the scholars’ position. Yet these scholars’ analyses still manage to take pride of place in the Updated Commentary.

Both works are guilty, of providing somewhat bootstrapped support. The Updated Commentary relies frequently, and for some points exclusively, on the ICRC’s own publications and studies. For instance, ICRC products are the sole sources in many footnotes to the commentary on common Article 3. To be fair, many of these ICRC sources rely on outside evidence to make the points cited by the Updated Commentary. However, the ICRC’s Study on Customary International Law is among the ICRC sources most frequently cited and was criticized for bootstrapping as well. Meanwhile, although the DOD Manual does the same or more, bootstrapping seems of comparatively less (though is not without) concern in international law when conducted by a State rather than a private actor. Still the highly selective citations of the DOD Manual have already alienated a number of readers (see, e.g., here and here).

On occasion, the Updated Commentary seems to say too much. For instance, noting that special agreements between Parties may not be used to avoid the Convention’s obligations, the Updated Commentary observes:

This ‘non-derogability’ of international humanitarian law is nowadays widely accepted and may be seen as an indication of the jus cogens character of its rules. (Para. 978.)

The latter proposition is strange in light of the Convention’s Article 63 withdrawal provisions. Article 63 provides in relevant part, “Each of the High Contracting Parties shall be at liberty to denounce the present Convention.” If, as the Updated Commentary asserts, the Conventions’ obligations reflect law that preempts all other legal obligations, even subsequent attempts at withdrawal, abandonment, or disavowal, then the Conventions’ own provisions for such denunciation are reduced to surplusage. The observation seems to overreach and was certainly unnecessary to even the most thorough explanation of Article 6 special agreements.

Likewise, a comment on the common Article 3 obligation to resort only to “regularly constituted courts,” observes “Judges must have the security of tenure” (para. 680). The paragraph’s only citation not derived from a human rights instrument or an ICRC source is the US Supreme Court’s Hamdan v. Rumsfeld plurality opinion. Yet on examination, the cited passage from Hamdan provides for nothing of the sort. In fact, the Hamdan Court observes with respect to regularly constituted courts that “Common Article 3 obviously tolerates a great degree of flexibility in trying individuals captured in armed conflicts; its requirements are general ones, crafted to accommodate a wide variety of legal systems” (at para. 635).

Similarly with respect to offers of humanitarian aid the Updated Commentary provides:

Unlike humanitarian law applicable to international armed conflicts, no treaty-based rules specifically address whether High Contracting Parties, other than those which are party to a non-international armed conflict, have an obligation to allow and facilitate the rapid and unimpeded passage of relief consignments, equipment and personnel.[790] It could be argued, at least tentatively, that this may be considered to be compulsory on the basis of the due diligence component enshrined in common Article 1 (‘ensure respect’). (Para. 840.)

The argument is one that is sure be taken up by advocates and perhaps even reinforced to the satisfaction of a tribunal by its inclusion in the Updated Commentary. Yet to imply such an obligation from the scant text of common Article 3 seems to render the Additional Protocol I, Article 70 specific obligations in this regard superfluous. The Updated Commentary might simply be better without such suggestions at all.