GC IV Commentary Series – Individualization in Civilian Internment Decisions
Editors’ note: The following series considers ICRC’s 2025 updated Commentary on the Fourth Geneva Convention. Rosa-Lena Lauterbach, Liisi Adamson, and Sean Watts’s introduction to the series is available here.
The Fourth Geneva Convention of 1949 regulates the treatment of civilians in international armed conflict and occupation. Among its most consequential rules are those that permit States, in limited circumstances, to intern civilian protected persons. Civilian internment is not punishment, but rather a preventive security measure. Nonetheless, it is one of the most severe measures of control the Convention allows a belligerent to impose on a protected civilian.
This post examines the rules establishing when States may intern civilian protected persons under the Convention. Motivating our inquiry is the ICRC’s recently published updated Commentary to the Fourth Geneva Convention. The updated Commentary reaffirms the Convention’s protective purpose and offers a contemporary account of how its rules, including those relating to internment, should be understood in light of State practice, jurisprudence, scholarship, and operational experience.
In particular, we focus on the notion of individualization of internment decisions. In its updated Commentary, the ICRC endorses the view that initial internment decisions must be made on an individual, case-by-case basis. In this post, we examine what individualization means, whether States accept it as a requirement, and what its operational implications are for civilian internment decisions during international armed conflict.
We propose distinguishing between two legal forms of individualization: procedural individualization, which requires States to afford distinct decision procedures to each potential civilian internee; and substantive individualization, which requires States to determine that a civilian candidate for internment constitutes a sufficient threat to security to justify internment. These two forms of individualization serve different purposes. Distinguishing between them clarifies the legal analysis. We argue that States should be deliberate and particular in adopting legal positions with respect to each form. In this post, we focus on procedural individualization, which is the form the ICRC endorses with respect to internment decisions under the Fourth Convention.
Measures of Control Under the Convention
The Fourth Geneva Convention protects “civilian persons in time of war.” But its protections do not apply to all civilians in the same way. For example, the Convention distinguishes between general protections that apply to “the whole of the populations of the countries in conflict” (Part II), and protections that cover only “protected persons” as defined in Article 4 (Part III). Additionally, Part III protections are further divided into those rules governing protected persons during international armed conflict (Part III, Section II), rules that apply during occupation (Part III, Section III), and rules that apply in either context (Part III, Section I).
Internment arises in the context of the Convention’s rules governing “protected persons” (Part III). Furthermore, internment must be understood as one of innumerable measures of control belligerents may take with respect to civilians. As Article 27 of the Convention notes, belligerents “may take such measures of control and security in regard to protected persons as may be necessary as a result of the war.”
The Convention does not provide a list of available measures of control. The 1958 Commentary to the Fourth Convention notes “a great many measures,” including “comparatively mild restrictions such as the duty of registering with and reporting periodically to the police authorities, the carrying of identity cards or special papers, or a ban on the carrying of arms,” as well as “harsher provisions such as a prohibition on any change in place of residence without permission, prohibition of access to certain areas, [and] restrictions of movement.” The updated Commentary adds the following measures to the list: “establishing checkpoints, searching property or persons[, and] interrogating protected persons,” as well as “digital forms of surveillance” and “restrictions on the property of protected persons” (para. 2352).
Assigned residence and internment are thus only two of the many available measures of control. That said, they are “the two most severe measures a belligerent may inflict on protected persons.” As a general rule, assigned residence is a less serious measure than internment. Although the Fourth Convention addresses internment and assigned residence together, for purposes of this post we will focus solely on internment.
The Legal Standard for Civilian Internment
For all its rules governing internment, the Convention does not define what internment is. The 1958 Commentary calls internment a “form of assigned residence, since internees are detained in a place other than their normal place of residence.” Furthermore, internment “implies an obligation to live in a camp with other internees.”
The updated Commentary further describes internment as “depriving a person of their liberty, typically at an internment camp or other place established for that purpose” (para. 2873). Internment refers to “non-criminal measures ordered against a protected person based on the serious threat that their activities pose to the security of the Detaining Power in the context of an armed conflict” (para. 2872). The ICRC further notes that internment and assigned residence are “both non-criminal and non-punitive in nature,” meaning that their “aim is not to establish responsibility for a crime or to punish an individual for it, but to ensure the security of the Detaining Power” (para. 2868).
Internment may occur in two contexts. The first is international armed conflict. In this context, internment decisions are governed by Articles 41-43 of the Fourth Convention. The second context is belligerent occupation. Here, internment decisions are governed by Article 78. Section IV of Part III goes on to impose a wide array of regulations for the treatment of internees.
Although internment decisions are distinguished in these two contexts, the legal standard is similar. According to Article 42(1), States may intern protected civilians “only if the security of the Detaining Power makes it absolutely necessary.” Article 78 allows internment of civilians when the occupying power deems it “necessary, for imperative reasons of security.”
The 1958 Commentary to Article 78 explains that the legal standard for internment during occupation is comparable to that for armed conflict contexts. Although the 1958 Commentary suggests that Article 78 contains a more stringent internment standard than Article 42(1), the updated Commentary concludes that “it is difficult to discern any substantive difference between the two provisions” (para. 4264). Although this is subject to debate, we will assume for purposes of this post that the two legal standards are similar, if not equivalent.
Individualization: Procedural and Substantive Forms
Although the Fourth Convention expressly provides for civilian internment, it is less clear on other questions, one of which is the matter of individualization of internment decisions. In the updated Commentary, the ICRC “endorses” the view that internment decisions must “be taken on an individual, case-by-case basis” (para. 2898). Before diving into the merits of this view, we want to first distinguish between two forms of individualization: procedural and substantive.
Procedural individualization refers to a requirement that States make distinct determinations for each individual civilian whom they are considering for internment. Procedural individualization is thus not focused on whether and the extent to which a civilian satisfies the requirement for internment (namely, “absolutely necessary” to protect the “security of the Detaining Power”). Rather, it addresses a process-orientated concern that the civilian should receive decision procedures tailored to his or her specific circumstances.
Substantive individualization, in contrast, is the idea that States must determine whether potential civilian internees sufficiently pose a security threat, making their internment “absolutely necessary.” This form of individualization is thus focused on whether a civilian’s internment is justified under the applicable legal standard. This will be a factual determination, accounting for matters such as the protected civilian’s membership and affiliation, beliefs, public speech, and personal conduct.
Distinguishing between these two forms of individualization brings into contrast different concerns about the internment decision process. For example, it may be controversial whether a civilian’s membership in a particular group that poses a threat to the State is sufficient to meet the “absolutely necessary” standard and thus justify the civilian’s internment. Furthermore, if membership alone is not sufficient, questions arise as to what acts or conduct may justify internment. For example, is advocacy for the group sufficient? Is performing administrative or logistical acts on behalf of the group enough?
Difficult as the questions above may be, it should be clear that they all concern matters of substantive individualization (not procedural individualization). The questions all concern the extent to which a civilian constitutes or contributes to a security threat justifying internment. Note that substantive individualization perhaps becomes thorniest in situations in which a group constitutes a security threat to the belligerent State. In such situations, difficult questions may arise about the character of group members’ respective contributions to the threat.
But these questions of substantive individualization would arise regardless of whether civilian candidates for internment are afforded discrete procedural assessments. In other words, regardless of whether procedural individualization is a legal requirement (as we will see, this is far from clear), these substantive issues will arise in an application of the Article 42(1) legal standard and will remain open to debate.
Likewise, conceding that Article 42(1) requires procedural individualization to potential internees does not absolve States from wrestling with the substantive questions, nor does it move any way toward resolving those issues.
Assessing The ICRC’s Endorsement of Procedural Individualization
As previously discussed, in the updated Commentary to the Fourth Convention, the ICRC “endorses” a legal requirement that internment decisions for civilians “be taken on an individual, case-by-case basis” (para. 2898). Here, we take the ICRC to be endorsing procedural individualization.
Is it true that Article 42(1) requires procedural individualization? The standard approach to treaty interpretation set forth in Article 31 of the Vienna Convention instructs States to interpret the treaty “in good faith” according to the “ordinary meaning to be given to the terms of the treaty in their context and in the light of its object and purpose.” The context of the treaty terms subject to interpretation includes the entirety of the treaty text. Additionally, treaty interpretation must account for “any subsequent practice in the application of the treaty which establishes the agreement of the parties” on the interpretive question.
Article 32 of the Vienna Convention allows recourse to a treaty’s “preparatory work” and the “circumstances of its conclusion” either to confirm the meaning resulting from the application of Article 31, or when the text subject to interpretation remains unclear. Article 32 thus provides a “supplementary” rule to the primary interpretive rule in Article 31.
Text and Context
We thus first turn to the text of the treaty itself. The text does not expressly address the question of individual or collective internment decisions. As the 1958 Commentary and the updated Commentary both explain, the omission was deliberate. At the Diplomatic Conference at which the Convention was drafted, an amendment to the treaty text asserting that internment decisions “should be taken individually” was rejected (more on this below).
Additionally, the text of Articles 41 and 42 of the Fourth Convention both speak of protected persons in the plural form when discussing internment and assigned residence. Notably, the second paragraph of Article 42, which discusses voluntary internment, switches to the singular form when discussing individuals who request such internment. (It is perhaps further noteworthy that the term protected persons is defined in the plural form in Article 4.)
Another distinction in the singular/plural usage occurs between Article 42(1) and Article 43, which governs subsequent review of internment decisions. In addressing the review procedures to which an interned protected person is entitled, Article 43 shifts to the singular form by stating that any “protected person” is entitled to have his or her internment reconsidered. The text further provides for review of “his or her case” by a court or administrative board.
This grammatical contrast may suggest that Article 42 permits initial internment decisions to be made through a collective determination procedure. Thus, the ICRC may be correct that procedural individualization is required, but incorrect as to the timing of the requirement. On this view, States are legally obligated to conduct individualized determinations only at the post-internment review phase.
It should be noted that, on the question of procedural individualization, the 1958 Commentary appears to distinguish the legal standards for internment during occupation and international armed conflict. With respect to occupation, the Commentary asserts “there can be no question of taking collective measures” and that “each case must be decided separately.” The Commentary adopts this view despite the fact that, similar to Article 42(1), Article 78 also uses the plural form when setting forth the civilian internment standard. (The updated Commentary does not address this distinction, as it supports individualized procedure under both Articles 42(1) and 78).
Object and Purpose
The rule of interpretation also requires consultation of the Convention’s object and purpose. Underlying any analysis is the general notion that the object and purpose of all law of armed conflict treaties, including the Geneva Conventions of 1949, reflect a balance between humanitarian considerations and military necessity. The object and purpose of the Fourth Geneva Convention specifically is to protect civilians during armed conflict while also defining the limits of permissible measures that may be implemented for the sake of the belligerent’s security and control (p. 66). It does this by authorizing the restriction of protected persons, while also setting limits on how belligerents implement those restrictions.
This understanding influences the interpretation as we consider the most significant permissible measure that may be taken, internment, and how to implement this measure of control in a manner that is consistent with the Convention’s object and purpose. In doing so, the implementation of internment must balance the humanitarian protections afforded to civilians with the legitimate security interests of the detaining power.
Negotiating History
Before moving on to State practice and doctrine, it is worth revisiting the Convention’s drafting history (travaux préparatoires) on the matter of procedural individualization. The 1958 Commentary noted States considered whether to require individual internment decisions. As the Commentary states, “the Diplomatic Conference discussed at great length whether the [assigned residence and internment] provision should be amended to state that any decision concerning assigned residence or internment ‘should be taken individually.’”
As the Commentary explains, “The proposal was rejected … on the ground that there might be situations—a threat of invasion for example—which would force a government to act without delay to prevent hostile acts, and to take measures against certain categories without always finding it possible to consider individual cases.” The Commentary also noted that the “safeguards provided in Article 43 seem adequate to reduce the risk of arbitrary decisions.” The treaty drafters’ consideration and rejection of an explicit individual decision requirement strongly suggests that the treaty was intended to allow flexibility in making initial internment determinations while preserving individualized review procedures under Article 43.
In the updated Commentary, the ICRC expounds on the discussion at the 1949 Conference (endnote 17). The updated Commentary describes discussions at the Diplomatic Conference as reflecting a concern “about the potential impracticality of requiring internment … to be ordered on an individual basis in certain circumstances of armed conflict.” The ICRC notes that the United States was one of the concerned States, considering “that excluding collective internment was impractical, as in times of emergency, such as when a country is threatened with invasion, ‘the government may feel compelled to act immediately to prevent potential hostile action by enemy aliens.’” Furthermore, the United States argued that “in cases of collective internment, subsequent review would guard against arbitrary detention.” The ICRC noted some States, including Italy and Austria, “argued in favour of wording that emphasized the exceptional nature of internment and mitigated against measures of collective internment.”
Subsequent State Practice
In the updated Commentary, the ICRC seems to argue that the law has changed since 1949, such that procedural individualization for internment decisions is required under Article 42 of the Convention. The ICRC’s support for its argument is set forth in an endnote, in which it cites the International Criminal Tribunal for former Yugoslavia (ICTY) Delalić case, the military manuals of Belgium, Denmark, and Norway, and four works of scholarship (n. 18). Given limitations of space, we will confine our analysis to the Danish Manual and the Delalić case. (We set aside issues concerning the precise methodological relevance of military manuals and case law in the context of interpreting subsequent State practice.)
At first glance, the 2016 Danish Military Manual does indeed appear to support procedural individualization for internment decisions. But some ambiguity arises upon closer examination. The Manual first requires an “individual assessment of whether the civilian in question poses a qualified security risk” (p. 488). It then provides that “[i]t is not permitted to intern civilians collectively on the ground of their nationality, religion, or other characteristics” (p. 488). The meaning of the phrase “other characteristics” is not explained, making the scope of the prohibition uncertain.
More importantly, the relationship between these two statements is not self-evident. This second qualifying sentence is difficult to reconcile with the first. If the Manual intends to require individualized procedures in every case, the second sentence may be unnecessary. Instead, by prohibiting collective internment only on specified grounds, the text arguably leaves open the possibility that collective determinations may be permissible in other circumstances.
This ambiguity also raises the possibility that the first sentence is directed more at the substantive, rather than procedural, aspects of individualization. Such an interpretation would also explain why the Manual expressly prohibits collective internment based on nationality, religion, or other characteristics, yet does not foreclose collective determinations involving groups defined by other criteria, such as affiliation with a non-State armed group. On this view, a civilian’s nationality or religion (or that of a group of civilians) could not serve as the substantive basis for internment, although perhaps other of the civilian’s affiliations could.
Similarly, the Delalić trial judgment in the ICTY appears to support procedural individualization. The judgment states that internment decisions should be made only after “careful consideration in each individual case” and that “such measures are never taken on a collective basis” (para. 578). But when read in context, the decision is less clear.
Before discussing the need for individual review, the judgment explains that the mere fact that a national is aligned with the enemy is never, by itself, a sufficient basis for internment (para. 577). Rather, internment must be based on an assessment of whether the civilian’s activities, knowledge, or qualifications present a threat to security. The decision also asserts that military age alone does not necessarily justify internment. These statements suggest that the emphasis on individualization is substantive. The judgment goes on to explain that the procedural safeguard is the individual review required by Article 43 (para. 583), which potentially further clouds the issue by failing to carefully distinguish pre- and post-internment procedural requirements.
It should be noted further that the trial court judgment ultimately based its factual findings on concerns about what appeared to be matters of substantive individualization. The focus of the Court’s analysis was not the defendants’ failure to afford individualized procedures, but rather the fact that internment appeared to constitute “a collective measures aimed at a specific group of persons, based mainly on their ethnic background” (para. 1134). Furthermore, in determining guilt for unlawful internment, the court relied heavily on the defendants’ failure to comply with post-internment review procedures required under Article 43 (paras. 1135-1141). These elements cast further doubt on the strength of the judgment’s support for a legal requirement of procedural individualization.
Even if the Belgian, Danish, and Norwegian manuals do in fact support the ICRC’s endorsement of procedural individualization as legally required under Article 42(1), this does not definitively establish the matter. The interpretive element focusing on subsequent State practice requires that such practice “establishes the agreement of the parties” to the Convention that procedural individualization is a legal rule. The positions of three States do not seem sufficient to meet this standard.
Most States do not adopt a public position on the matter of procedural individualization under Article 42(1). Other States offer a more equivocal view. Consider, for example, the position taken by the United Kingdom in its Joint Services Manual on the Law of Armed Conflict. The UK Manual initially refers to internment or assigned residence decisions of “protected persons,” allowing the possibility that collective determinations are possible (p. 229-30). It then shifts to the singular form only to clarify a substantive limitation, namely that “the mere fact that a person has enemy nationality and is of military age does not justify internment” (p. 230).
The U.S. Department of Defense Law of War Manual presents a similar view. Section 10.9.2 addresses separately the initial internment decision and the subsequent appeal and review procedures. On the former, the Manual mirrors the language of Article 42 by referring to “protected persons” in the collective sense (sec. 10.9.2.1). Then shift to the singular when prescribing the procedures governing the review of detention (sec. 10.9.2.3). This parallel structure reinforces the procedural distinction between collective internment determinations and individualized subsequent review.
We use these few examples not to demonstrate that these States have taken definitive stances with respect to procedural individualization as a legal requirement for initial civilian internment decisions. Rather, we more modestly claim that evidence is lacking that States have coalesced around a definitive position. Furthermore, we hope to have shown that closer attention to the procedural-substantive distinction for individualization reveals that greater clarity and precision may be helpful when States set forth their views about the law.
Conclusion
This post has examined the Fourth Geneva Convention’s rules establishing when States may intern protected persons under Article 42(1). The ICRC insists that initial internment decisions must be made on an individual, case-by-case basis. Having examined the text and context, object and purpose, drafting history, and subsequent State practice, we conclude that the legal standard for individualization in internment decisions remains unclear.
We suggest that this ambiguity might be resolved by understanding initial internment decisions as involving two distinct legal analyses: procedural; and substantive. Procedural individualization requires States to afford distinct decision procedures to each potential civilian internee while substantive individualization requires States to determine that a civilian candidate for internment constitutes a sufficient threat to security to justify internment. We argue that States should be deliberate in articulating legal positions with respect to each form. Greater clarity regarding the legal requirements for internment decisions would provide more meaningful guidance to those responsible for making and reviewing internment decisions in practice.
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LTC Christina Colclough is an assistant professor in the Department of Law and Philosophy at the United States Military Academy.
Robert Lawless is an Associate Professor in the Department of Law and Philosophy and Research Director of the Lieber Institute for Law and Warfare at the United States Military Academy, West Point.
The views expressed are those of the authors, and do not necessarily reflect the official position of the United States Military Academy, Department of the Army, or Department of Defense.
Articles of War is a forum for professionals to share opinions and cultivate ideas. Articles of War does not screen articles to fit a particular editorial agenda, nor endorse or advocate material that is published. Authorship does not indicate affiliation with Articles of War, the Lieber Institute, or the United States Military Academy West Point.
Photo credit: Nationaal Archief via Wikimedia Commons
