the denial theory

The idea that a capturing power may deny POW status to its own individuals when they have joined the enemy can be traced to medieval times,Footnote ³³ and it is no surprise that such a position was supported by classic scholars of international law such as Baltazar Ayala,Footnote ³⁴ Cornelius van Bynkershoek,Footnote ³⁵ Hugo Grotius,Footnote ³⁶ and Emmerich de Vattel.Footnote ³⁷ This theory remained very popular in the writings of scholars of the nineteenth and twentieth centuries, despite the adoption of international treaties regulating POW status. Among them one can list the opinions of Sherston Baker,Footnote ³⁸ Hannis Taylor,Footnote ³⁹ Paul Fauchille,Footnote ⁴⁰ Herbert Fooks,Footnote ⁴¹ William Flory,Footnote ⁴² Antonio Guerrero Burgos,Footnote ⁴³ Myres McDougal and Florentino Feliciano,Footnote ⁴⁴ Howard Levie,Footnote ⁴⁵ Rupa C. Hingorani,Footnote ⁴⁶ and Yoram Dinstein.Footnote ⁴⁷ Although the popularity of the theory seems to have decreased in the twenty-first century, authors defending it include Robert Kolb,Footnote ⁴⁸ Leslie Green,Footnote ⁴⁹ Dinstein (again),Footnote ⁵⁰ and Ebrahim Afsah.Footnote ⁵¹ Having said that, the most influential scholar taking this position was Oppenheim, whose opinion dates back to the beginning of the twentieth century. As his opinion is constantly referenced by other authors, and heavily relied upon in certain judicial decisions on the issue, it is important to reproduce it in full. According to him,

As can be perceived from the referenced opinions, despite a lack of in-depth argumentation, several scholars mention the existence of a duty of allegiance to the detaining state as a basis for denying POW status. This idea is further restated in the judicial decision that has become the seminal case and authoritative reference for the denial theory: the 1967 Privy Council decision in Public Prosecutor v Koi. This case arose from the armed conflict between Indonesia and Malaysia in the 1960s and refers specifically to the capture of fourteen individuals of undetermined nationality (described by the court as Chinese Malays). They parachuted into Johore as part of a paratrooper force comprising thirty-four Indonesian soldiers. All of the individuals were acting under the command of Indonesian air force officers and wearing camouflage uniforms, and each was carrying “fire-arm, ammunition, two hand grenades, food rations and other military equipment.”Footnote ⁵³ During the trial phase, all of the fourteen individuals were found guilty of illegal possession of firearms and ammunition and were sentenced to death under Malaysian criminal law. The defence team for one of the accused, Teo Boon Chai, objected to the court’s jurisdiction, arguing that the defendant was neither Malaysian nor Indonesian and should be treated as a POW, but the objection was rejected by the judge. On appeal, the Federal Court quashed the conviction of two of the accused, Oie Hee Koi and Ooi Wan Yui, considering that there had been a mistrial due to their potential POW status. The prosecution appealed to the Privy Council, arguing that “a national of a Detaining Power, being a person who owed a duty of allegiance but had gone over to the enemy, was not entitled to the privileges accorded by the Convention to protected prisoners of war; neither was a person who, though not such a national, owed a duty of allegiance to the Detaining Power.”Footnote ⁵⁴

In its judgment, the Privy Council analyzed whether the accused were entitled to be treated as POWs under the act that incorporated the Geneva Conventions. The Privy Council noted that the instrument did not indicate directly whether individuals owing allegiance to the capturing state were entitled to POW status. However, the Privy Council decided that POW status does not cover the captor state’s own nationals and individuals who owe it allegiance. The decision was founded upon a “strong inference” that Geneva Convention III is an instrument “concerned with the protection of the subjects of opposing States and the nationals of other Powers in the service of either of them, and not directed to protect all those whoever they may be who are engaged in conflict and captured.”Footnote ⁵⁵ This reading was based in part on what was labelled the underlying assumption of the convention — that is, that POWs are individuals who are neither nationals of the detaining power nor bound to it by any duty of allegiance. The court inferred this assumption from the references to allegiance made in Articles 87 and 100 of Geneva Convention III and concluded that “a person who owes this duty to a Detaining Power is not entitled to prisoner of war treatment.”Footnote ⁵⁶ Curiously, the members of the Privy Council themselves conceded the weakness of their argument by affirming that “[i]f the matter rested on inference from these articles alone, the argument might not be conclusive.”Footnote ⁵⁷ In order to overcome this weakness, the court argued that such an inference “coincides … with commonly accepted international law,”Footnote ⁵⁸ which was proven by relying almost exclusively on the previously quoted opinion of Oppenheim.Footnote ⁵⁹

the conferral theory

A different set of scholars believes that defectors are entitled to POW status. This position emerged around the middle of the twentieth century and includes the opinions of scholars such as René-Jean Wilhelm,Footnote ⁶⁰ Eric David,Footnote ⁶¹ Gary Solis,Footnote ⁶² Els Debuf,Footnote ⁶³ David Cumin,Footnote ⁶⁴ Sten Verhoeven and Hilde Sagon,Footnote ⁶⁵ Emily Crawford,Footnote ⁶⁶ and Heike Niebergall-Lackner.Footnote ⁶⁷ The arguments in favour are predominantly legal and include the fact that no express exception was introduced in Article 4 of Geneva Convention III, and, therefore, nationality has no role to play in determining POW status.

When it comes to state practice, several cases from the United States seem to reaffirm this position. The first case is Ex Parte Quirin, in which the Supreme Court of the United States dealt with the writs of habeas corpus of eight captured Nazi saboteurs who entered US territory in a German U-boat during the Second World War, discarded their uniforms, and conspired to attack war industries and facilities. Upon capture, they were treated as unlawful combatants not entitled to POW status and were subjected to trial and punishment by a military tribunal. The US Supreme Court rejected their petition, reaffirming the denial of POW status to unlawful combatants and the legality of their trial before a military commission. Nonetheless, as two of the captured individuals were American citizens, the court clarified that “[c]itizens who associate themselves with the military arm of the enemy government, and with its aid, guidance and direction enter this country bent on hostile acts, are enemy belligerents within the meaning of the Hague Convention and the law of war.”Footnote ⁶⁸ A way to understand this position is that nationality and allegiance do not affect belligerent status and that, had these individuals not discarded their uniforms to commit acts of sabotage behind enemy lines, they would have been granted POW status upon capture irrespective of their American nationality. In fact, this conclusion was clearly reached by the US Ninth Circuit Court of Appeals in another Second World War case: In re Territo. In that case, an American citizen, who was captured by Allied forces while serving in the enemy Italian army, raised a writ of habeas corpus against his detention as a POW based on his American nationality. The court of first instance found that US citizenship was immaterial to the legality of detention as a POW, and, on appeal, the court affirmed: “We have reviewed the authorities with care and we have found none supporting the contention of petitioner that citizenship in the country of either army in collision necessarily affects the status of one captured on the field of battle.”Footnote ⁶⁹

These cases from the United States have been recognized as settled practice by the US executive. For instance, both cases are quoted in a memorandum of the Department of Justice when affirming that all individuals (regardless of citizenship) who associate with the enemy are enemy belligerents and that “[n]othing further need be demonstrated to justify their detention as enemy combatants.”Footnote ⁷⁰ In 2004, an American national, Yaser Esam Hamdi, brought a writ of certiorari against his detention after being caught fighting with the Taliban in Afghanistan.Footnote ⁷¹ The US Supreme Court reaffirmed the rule that nationality does not alter the status of enemy combatants and that their detention becomes a simple war measure to prevent these individuals from rejoining the enemy and continuing to participate in hostilities. In this case, the court expressly stated that

The most important aspect to highlight is that among academics supporting this theory there are two currents that relate to the effects of POW status. Authors such as Levie,Footnote ⁷³ Wilhelm,Footnote ⁷⁴ Yutaka Arai-Takahashi,Footnote ⁷⁵ David,Footnote ⁷⁶ Tse Ka Ho,Footnote ⁷⁷ Debuf,Footnote ⁷⁸ and Niebergall-LacknerFootnote ⁷⁹ have adopted a reconciliatory position in which the defector gets POW status but can be tried for treason by the capturing state in any case. For them, POW status functions as a set of judicial guarantees that must be respected during trial, but the charges and punishment raised against a defector remain at the discretion of the capturing state. This current will be referred to as the soft-conferral theory in this article. The opposite current (the full-conferral theory) will be the object of analysis in the next part.

customary international law

The idea that the denial theory derives from customary international law was argued by the Privy Council in the Koi decision when affirming that the theory is consistent with generally accepted international law.Footnote ⁸² Some authors such as HingoraniFootnote ⁸³ and Marco SassòliFootnote ⁸⁴ have made similar affirmations. In order to argue the existence of a customary rule, it is necessary to discover instances of practice relevant to the topicFootnote ⁸⁵ that are sufficiently widespreadFootnote ⁸⁶ and consistentFootnote ⁸⁷ to dissolve any doubts regarding the existence of an opinio juris. Footnote ⁸⁸ Such exacting requirements make the identification of relevant practice very difficult and that is probably why — for the most part — authors who support the denial theory rarely point to any state practice other than the Koi case.

Admittedly, most of the historical precedents that could be uncovered show a tendency of states to deny POW status to defectors. For instance, during the First World War, Austria-Hungary denied POW status to its own subjects, such as the Italian irredentists Cesare BattistiFootnote ⁸⁹ and Nazario Sauro, who were captured serving in Italian formations, judged for treason, and executed shortly thereafter.Footnote ⁹⁰ Historians have also reported some examples from the Second World War. Although Germany treated Free French Forces captured in 1942 in Bir-Hakeim as POWs (for fear of retaliation by the Allies), captured Germans serving in the French Foreign Legion “were subjected to immediate execution as traitors.”Footnote ⁹¹ Similarly, thirteen French volunteers fighting within Nazi formations (known as the Thirty-Third Waffen-SS Charlemagne Division), who were captured by American forces, were summarily executed when handed over to the Free French Forces of the Second Armoured Division under the command of General Leclerc, in Bad Reichenhall, on the last day of the war.Footnote ⁹² Perhaps due to such expected treatment, British and French forces provided their German members with fake non-German sounding names and documents in case of capture by German forces.Footnote ⁹³

One of the most interesting examples is the case of the nearly twenty-eight thousand Soviet nationals serving in German uniforms that were captured by the Allies. According to Nigel Cawthorne, these individuals were initially captured by the Germans, who reported them as POWs to Soviet authorities via the Swiss government but, due to the fact that the Soviets had not signed the 1929 Geneva Convention for the Protection of Prisoners of War (1929 Geneva Convention) and denied the existence of virtually any POWs, they were abandoned to their luck in German captivity.Footnote ⁹⁴ The Germans felt freed from their obligations under the 1929 Geneva Convention, and no food parcels were sent to the Soviet prisoners by their motherland, resulting in the very real risk of starvation, which forced them to volunteer for German work groups in order to receive better food rations. As Cawthorne points out, “[l]ater these groups were armed and given German uniforms. Anyone who objected to this forcible induction into the German army was shot.”Footnote ⁹⁵ When the Allied forces captured these individuals, American authorities asked the Soviets what to do with them, but Soviet authorities maintained their denial of the existence of Russians serving in German ranks.Footnote ⁹⁶ Later on, while engaging in negotiations for the repatriation of POWs, the Soviets informed their American counterparts that they expected “that all liberated Soviet nationals be treated as free citizens, not as prisoners of war.”Footnote ⁹⁷ British and American authorities accepted these conditions and forcefully repatriated them despite their evident wish to the contrary and some suicide attempts triggered by their fear of Soviet retaliation.Footnote ⁹⁸ As Pavel Polian has noted, from the beginning of the war until October 1941, Soviet authorities had executed 10,221 repatriated soldiers who were considered traitors.Footnote ⁹⁹ By 1946, around 339,618 individuals, including the Vlasovtsy,Footnote ¹⁰⁰ were sent to the gulags and labour camps in an act of “great leniency” by the Soviet Union.Footnote ¹⁰¹

Despite those examples (of which there might be more), it is important to question whether state practice on this issue can constitute a customary rule of international law. The International Court of Justice has repeatedly stated that varied, inconsistent, divided, and sporadic practice represents a lack of uniformity and consistency, which impedes the formation of a customary rule.Footnote ¹⁰² In addition, the court has highlighted that discrepancies in practice due to political considerations evidence a lack of uniformity and consistency of state practice. This was clearly set out in the Asylum case,Footnote ¹⁰³ where the court rejected the existence of a customary rule on the basis that state practice displayed “so much uncertainty and contradiction, so much fluctuation and discrepancy … so much inconsistency”Footnote ¹⁰⁴ and particularly that “the practice has been so influenced by considerations of political expediency in the various cases that it is not possible to discern in all this any constant and uniform usage, accepted as law.”Footnote ¹⁰⁵

Caution must also be exercised when addressing such state practice since, upon closer examination, there is ample evidence that political reasons have determined the treatment of captured defectors. For instance, from the few examples previously mentioned, one should note that the execution of the French volunteers of the Waffen SS referenced above has been linked to an incident of personal sensitivity rather than a legal position regarding POW status. According to Jonathan Trigg, “General [Leclerc] asked the volunteers why they were wearing a German uniform. One of the volunteers shot back a reply asking the General why he was wearing an American one. It sealed the men’s fate. A firing squad was hastily convened and the prisoners were taken to local farmland and shot on the spot.”Footnote ¹⁰⁶ Additionally, the Allied treatment of Soviets fighting in German uniform seems to have been motivated by the fact that American authorities were more concerned with recovering their own servicemen, who had been liberated by the Soviets, than with the status or fate of the captured Soviets upon their return to the Soviet Union.Footnote ¹⁰⁷

More importantly, attention should be given to the fact that there is abundant evidence of inconsistency in the practice of several states. A global comparative study exceeds the scope of this article; nonetheless, a few examples regarding the practice of key states show the zigzagging of domestic policies in this field. Just as the United Kingdom has deviated from long-standing precedents regarding the denial of POW treatment to internal traitorsFootnote ¹⁰⁸ — for instance, during the American revolutionFootnote ¹⁰⁹ — so has it deviated from its denial of POW status to defectors. For instance, during the War of 1812, several British-born seamen on board US ships were captured by the British, denied POW status, and sent to England to be tried for treason. Nonetheless, since the United States had captured a similar number of British individuals, British detainees were not treated as traitors and were eventually exchanged for British POWs, a decision that Sir Alexander Cockburn attributes to fear of “the horrors of reciprocal and indefinite retaliation.”Footnote ¹¹⁰ In fairness, the British Crown did proclaim through the prince regent shortly afterward that allegiance was perpetual and, thus, that any person who voluntarily served on a ship of war of the United States was guilty of treason.Footnote ¹¹¹

However, during the Boer War, Irishmen fighting for the South African Republic were treated as POWs, with the British secretary for war and the financial secretary to the War Office reportedly affirming that the Irish “cannot be treated differently from other prisoners of war … [and should be] treated in the same way as their Boer comrades — as ordinary prisoners of war.”Footnote ¹¹² Finally, during the Second World War, a considerable number of Indians belonging to the Imperial British Army deserted upon instigation by the Japanese and joined the ranks of a nationalist force (the INA) fighting British colonial domination and seeking the independence of India. The INA’s military campaign was not successful, and many members of the INA were captured by the British; their captivity was kept secret from public opinion, and they were temporarily treated as POWs.Footnote ¹¹³ After conducting investigations, the British classified Indian members of the INA in three groups, freeing and dismissing from prosecution the members of the first two groups.Footnote ¹¹⁴ Due to the political circumstances of the time, members of the last group, who would have been considered perfect traitors and executed after trial under other circumstances — were only put on trial if they had been responsible for the brutal treatment or the death of a British or Allied subject.Footnote ¹¹⁵ This was due to the political environment of the time as “[p]ublic opinion had already judged the men [potentially facing trial as] heroes and patriots”Footnote ¹¹⁶ and because India’s imminent independence prevented the United Kingdom from punishing them as it would “leave a legacy of hatred and was likely to produce an immediate outbreak of violence.”Footnote ¹¹⁷ For these reasons, the British only opened three court martial cases, all of which were permeated with political arguments by the defendants claiming that the crimes of which they were charged were inapplicable since the defendants were “waging war for the liberation of India according to the rules of warfare which applied to the status of belligerents.”Footnote ¹¹⁸ The defendants were found guilty of waging war against the king, but the army chief, Claude Auchinleck, upon confirming the findings and sentences in the first cases, decided to “show clemency in respect to the sentence of transportation for life, which he remitted.”Footnote ¹¹⁹

Inconsistency is also present in the practice of the United States. Perhaps the clearest codification of the denial of POW status is found in the Lieber Code, which, in Article 48, established that “[d]eserters from the American Army, having entered the service of the enemy, suffer death if they fall again into the hands of the United States.”Footnote ¹²⁰ In fact, the same article considered that the same treatment by the enemy against their own defectors serving in the American army “is not a breach against the law and usages of war, requiring redress or retaliation.”Footnote ¹²¹ Subsequent military documents from the United States reaffirm this position. For instance, the 1914 US manual entitled Rules of Land Warfare affirmed that certain individuals forming part of a levée en masse cannot claim belligerent status, including “deserters, [and] subjects of the invading belligerent.”Footnote ¹²² The same rule was replicated in the basic field manual of the Judge Advocate General in 1934Footnote ¹²³ and in the 1940 version of the Rules of Land Warfare. Footnote ¹²⁴ However, following the Second World War, US practice turned 180 degrees with the already mentioned cases of Ex Parte Quirin Footnote ¹²⁵ and In re Territo,Footnote ¹²⁶ in which nationality was not considered an impediment to treating an individual as an enemy belligerent for the purposes of detention. The 1956 version of the Rules of Land Warfare opened the door to denial when it listed those entitled to POW status on the basis of the 1949 Geneva Convention III but excluded from POW treatment those who “without regard to citizenship or military or civil status … give aid to an enemy government or persons adhering to it.”Footnote ¹²⁷ However, in the 2004 Hamdi case, the US Supreme Court reaffirmed the position that even US nationals can be detained as enemy combatants.Footnote ¹²⁸ Yet another shift occurred in cases such as that of John Walker Lindh, an American citizen and member of Taliban forces captured in 2001 in Afghanistan,Footnote ¹²⁹ who was put on trial in the US federal court and “was convicted of providing services to the Taliban government and carrying explosives on their behalf.”Footnote ¹³⁰

More recently, the 2015 US Law of War Manual ratifies this change and takes a clear position when including, in the list of persons who are not entitled to POW status, “persons who are nationals of the Detaining Power or its co-belligerents, such as a defector who subsequently is captured by the force from which he or she defected.”Footnote ¹³¹ The manual affirms that “[t]he special privileges that international law affords combatants generally do not apply between a national and his or her State of nationality,”Footnote ¹³² and it explains this on the basis of the same sources listed above, including the other rules of Geneva Convention III, the Koi case, and Oppenheim’s opinion. The manual thus concludes that “the privileges of combatant status are generally understood not to apply, as a matter of international law, between nationals and their State of nationality”Footnote ¹³³ and that “international law does not prevent a State from punishing its nationals whom it may capture among the ranks of enemy forces.”Footnote ¹³⁴ Part of the rationale adopted to justify this position is the fact that defectors are not regarded by the US manual to have fallen into the power of the enemy “since they have voluntarily chosen to switch sides.”Footnote ¹³⁵ Justifying this position, the US manual quotes a report of the UN Secretary-GeneralFootnote ¹³⁶ and a provision of an older version of the UK military manual that does not exist in its most recent version.Footnote ¹³⁷ In this author’s view, this reading of the Geneva Conventions is clearly contrary to authoritative interpretations that hold that the voluntary nature of the decision to surrender or defect is irrelevant to the denial of POW status.Footnote ¹³⁸

Similar inconsistent practice arose in Germany during the Second World War. According to Alexander Gillespie, Germany obliged Vichy France in Article 9 of the Franco-German armistice of June 1940 to forbid its nationals from fighting against the Reich in foreign armies and threatened to treat captured French nationals as franc-tireurs. A similar position was taken by Germany towards the Czechs and German Jews incorporated into enemy formations. However, Gillespie notes that “the Germans did not enforce this following De Gaulle’s promise that the Free French forces would abide by the Geneva Conventions.”Footnote ¹³⁹ Additionally, the same author affirms that German practice showed that “if they were captured wearing a uniform they were entitled to become a prisoner of war of the country they were fighting for.”Footnote ¹⁴⁰

An important detail to highlight is that most authors adopting the denial theory do not reference state practice beyond the seminal Koi case mentioned above and, therefore, doubts arise regarding its customary nature. Allan Rosas might be one of the few authors who references some provisions of military manuals as evidence of the existence of such an exception to the entitlement to POW status. In his 1976 text, Rosas affirms that the mentioned exception “is expressly stated in the British military manual and seems to be implicitly present in other similar manuals.”Footnote ¹⁴¹ However, a review of the most recent version of the UK manual shows the absence of such a provision; instead, it expressly accepts that “[i]t is not clear whether captives of the nationality of the Detaining Power are entitled to P[O]W status.”Footnote ¹⁴² A review of other current military manuals shows that the majority of them simply replicate the language of Geneva Convention III when determining who is entitled to POW status, including the same categories and the same known exclusions to POW status (spies and mercenaries), and therefore providing almost no guidance on the issue at hand.Footnote ¹⁴³ Some military manuals include further categories of individuals included or excluded from POW status, but none of them make reference to the nationals of, or the individuals owing allegiance to, the capturing power,Footnote ¹⁴⁴ except for the already mentioned US military manual of 2015.

With all of these elements in mind, it seems to this author that there is a lack of sufficient uniformity and consistency of state practice to ground a customary rule in line with the denial theory. Additionally, political and military reasons have forced states to adapt their practices and modify their positions to accomplish the most advantageous results in particular circumstances. It is evident that the denial theory coincides with more common incidents of war reported by historians. But supporters of the denial theory have been generally unable to point to a consistent and unified practice of states beyond the Koi case and the Lieber Code; instead, scholarly writings seem to constitute the bulk of the references used to justify this theory. This author accepts that many of the examples given here are historically removed, but more recent examples were unavailable despite best efforts to discover them. Perhaps others may contribute to the present discussion by adducing further instances of contemporary and global practice, but, for the time being, it is the opinion of this author that the available practice raises doubts as to the existence of a crystalized customary rule of IHL reflecting the denial theory.

underlying assumptions and unwritten requirements through treaty interpretation

A literal reading of Article 4 of Geneva Convention III would indicate that POW status is dependent on the individual belonging to any of the categories established therein, irrespective of nationality or allegiance. As will be shown, some state authorities argue for the existence of an underlying assumption and unwritten requirements of allegiance. Following the rules on the interpretation of treaties of the Vienna Convention on the Law of Treaties (VCLT),Footnote ¹⁴⁵ an interpreter is bound to analyze whether the terms of Article 4 of Geneva Convention III — interpreted in good faith and in accordance with their context, object, and purpose — are ambiguous, obscure, manifestly absurd, or lead to an unreasonable conclusion and thus require the use of the preparatory works of the convention as a supplementary means of interpretation.

Although the text of the treaty is clear, supporters of the denial theory sometimes make use of contextual interpretation by pointing to Article 87, which affirms that “the accused, not being a national of the Detaining Power, is not bound to it by any duty of allegiance,”Footnote ¹⁴⁶ and Article 100, which has a similar assumption when it states that “since the accused is not a national of the Detaining Power, he is not bound to it by any duty of allegiance.”Footnote ¹⁴⁷ In Koi, the Privy Council affirmed that the articles’ “reference to the duty of allegiance might fairly suggest the further inference that a person who owes this duty to a Detaining Power is not entitled to prisoner of war treatment.”Footnote ¹⁴⁸ Similarly, the US military manual affirms that other provisions of Geneva Convention III “assume that POWs are not nationals of the Detaining Power.”Footnote ¹⁴⁹

Although the assumption is evident in both articles, not all authors agree that such language proves the existence of an additional requirement of non-allegiance for POW status. Ka Ho has argued that the language in Articles 87 and 100 of Geneva Convention III is “descriptive, rather than normative”Footnote ¹⁵⁰ and that all references to non-allegiance in these articles were inserted to “redress the potential problems caused by article 87(1).”Footnote ¹⁵¹ This particular paragraph of Article 87 establishes that a POW cannot be sentenced by military courts of the detaining power to a penalty “except those provided for in respect of members of the armed forces of the said Power who have committed the same acts,”Footnote ¹⁵² and, thus, the two elements of the provision (not being a national and not owing allegiance to the detaining power) were inserted with the aim of avoiding a full assimilation of POWs with the detaining power’s own soldiers under military law and avoiding their consequent treatment as traitors if they tried to escape. If one follows this interpretation, the references to allegiance in Articles 87 and 100 of Geneva Convention III are not indications of an additional requirement for POW status but, simply, the rejection of a full assimilation between POWs and soldiers of the capturing power for judicial matters and a reminder or authorization to the judge “to reduce the penalty even below the minimum prescribed by law.”Footnote ¹⁵³

The language of both articles is clear and gives some strength to the denial theory. However, some strength does not mean an unequivocal answer to the question under analysis. Just as the Privy Council itself noted, it would be feeble to argue that the language of Articles 87 and 100 of Geneva Convention III is the sole justification for the theory of the denial of POW status on the basis of allegiance. The Privy Council was forced to pair such a contextual interpretation with “commonly accepted international law.”Footnote ¹⁵⁴ But, as has been shown before, state practice does not reveal a clear position due to its serious inconsistencies, and, thus, other elements must be looked at by anyone trying to confirm or disprove such a theory.

Oppenheim tried to point to another contextual element when affirming that the denial theory refers to apparent customary rules concerning the inviolability of the bearer of the white flag. According to him, the mission assigned to parlementaires “protects everyone who is charged with it, whatever his rank … but it does not protect a deserter. A deserter may be detained, court-martialled, and punished.”Footnote ¹⁵⁵ Although the rule does not mention allegiance and POW status, it can be inferred that the refusal to treat a defector as a parlementaire derives from the fact that nationality or allegiance owed to the detaining or receiving side nullifies any type of status under IHL. However, the exception for parlementaires seems to be recognized only by a very small number of contemporary sources, including only one military manualFootnote ¹⁵⁶ and one scholar who mentions it in his writings.Footnote ¹⁵⁷ On the contrary, most other manuals that include provisions on parlementaires do not mention exceptions regarding defectors, deserters, one’s own nationals, or individuals owing allegiance.Footnote ¹⁵⁸ In addition, Leslie Green has reported some contrary practice by the United Kingdom during the Falklands War. According to him, British forces sent an Argentinian POW as a parlementaire to call on the Argentinean side to surrender by a given time.Footnote ¹⁵⁹ Green does not explain how the POW was received by the Argentinians, but he does mention that acceptance of the proposal was to be signalled by “returning the P[O]W under the White Flag. Rejection of the summons to surrender would be indicated “by returning the P[O]W without his White Flag, although his neutrality [would] be respected.”Footnote ¹⁶⁰ This example shows that, in recent practice, UK forces expected the POW to receive full treatment as a parlementaire and to be returned to his captors despite his nationality, membership on the Argentinian side, and the duty of allegiance that derived from both of these facts. In this sense, it is uncertain whether the rule referenced by Oppenheim really exists or supports his position. In sum, contextual elements do not seem to provide particularly conclusive arguments in support of the existence of the requirement.

Unfortunately, the object and purpose of the convention also provides little guidance on this issue given that Geneva Convention III has no preamble that could clarify its object and purpose, due to the inability to reach an agreement on its text. The preamble of the 1929 Geneva Convention stated that its objectives included giving effect to “the duty of every Power to mitigate, as far as possible, the hardships of war and to alleviate the fate of prisoners of war”Footnote ¹⁶¹ as well as developing “the principles which have inspired the international conventions of The Hague, in particular the Convention concerning the Laws and Customs of War and the Regulations annexed to it.”Footnote ¹⁶² It is difficult to see how this protective spirit could be construed to allow for the denial of POW status on the basis of a requirement not included in the text of the convention itself.

Opinions on teleological elements also seem divided. Authors such as Susan Elman have argued for a teleological interpretation of Geneva Convention III that extends POW status to defectors because the “emphasis throughout the Convention is on the importance of the rights and privileges which prisoners of war ought to enjoy”Footnote ¹⁶³ and “[A]rticle 4 is a clear improvement and extension of earlier definitions of prisoners of war, surely done in the attempt to include as many persons as possible within the scope of the convention.”Footnote ¹⁶⁴ At the same time, scholars such as Yutaka Arai-Takahashi suggest following the reasoning of the International Criminal Tribunal for the former Yugoslavia (ICTY) in applying an allegiance test to interpret the meaning of the requirement of falling into the power of the enemy under Article 4 of Geneva Convention III. In this sense, allegiance would determine who is the real enemy “so that even nationals of a Detaining Power should not be excluded from POW status under the Third Geneva Convention.”Footnote ¹⁶⁵ The current author expected judicial interpreters in The Hague to make use of extensive teleological interpretation techniques and perhaps confirm Arai-Takahashi’s view, but, in a curious turn of events, the Trial Chamber of the ICTY in Prosecutor v Prilić et al. rejected such an extensive reading. The case concerned crimes committed by a non-state armed group — the Croatian Defence Council (HVO), an armed group of ethnic Croats in Bosnia — against its own members, who were not Bosnian Croats but, rather, Bosnian Muslims. The Trial Chamber decided that Muslim members of the HVO detained by their own forces could not be considered POWs because the requirements of the conventional definition of a POW under Article 4 of Geneva Convention III were not met. In this case, the court clarified that a “teleological interpretation seeking to establish the objective of the Third Convention unambiguously leads to the conclusion that only those persons belonging to the armed forces of a Party other than the detaining Party are concerned.”Footnote ¹⁶⁶ The Trial Chamber did not rely on allegiance to determine POW status and, instead, focused on auxiliary sources to confirm the meaning of the text of Geneva Convention III. Basing itself on Pictet’s commentary to Article 4 of Geneva Convention III, the Trial Chamber deduced that “a member of the armed forces may not be considered a prisoner of war unless he is captured by that party to the conflict against which the armed forces to which he belongs are fighting.”Footnote ¹⁶⁷ This interpretation was not challenged on appeal, but, nonetheless, the Appeals Chamber confirmed the findings of the Trial Chamber categorizing the individuals as civilians.Footnote ¹⁶⁸ Although the case does not refer to captured defectors, it shows a strict adherence to the requirements of Article 4 of Geneva Convention III and a refusal to expand the protections of POW status over situations not foreseen in the text of the convention through teleological interpretation.

Given the inconclusiveness of these means of interpretation, recourse to auxiliary methods of interpretation could be sought. There is at least one aspect of the preparatory works that is interesting for the topic of allegiance and POWs: the report from the conference of government experts in 1947.Footnote ¹⁶⁹ The 1947 conference was convened to discuss the revisions made by the 1937 meeting of international experts to the 1929 Geneva Convention in light of the experiences gained from the Second World War in order to draft a new humanitarian agreement for POWs. The experts at this conference, who were listed as “delegates,” seemed to have acted on behalf of their statesFootnote ¹⁷⁰ and effectively undertook part of the preliminary work to develop the Geneva Convention III of 1949. A section of the report from the conference of government experts discussing a provision concerning penal sanctions for POWs clearly affirms that

This understanding was reaffirmed by the majority’s rejection of the term “insubordination” that is contained in the second part of the article, on the basis that “it may give rise to the impression that the P[O]W owes allegiance to the [detaining power], which is not the case.”Footnote ¹⁷² The solution adopted to determine which penal legislation binds POWs was to assimilate POWs to soldiers of the detaining power. However, the assimilation was not absolute, and the fact that POWs “remain enemies whose patriotism must be respected” was taken into account in order to avoid punishment for certain acts that, when committed by a regular soldier of the detaining power, would constitute serious crimes but, when committed by a POW, would lack enough links to the detaining power to consider them criminal.Footnote ¹⁷³ In this sense, allegiance as an underlying concept helps prevent undue assimilation for the purpose of determining sanctions, and, thus, as Jean Pictet’s commentary mentions, “an attempt to escape, for instance, cannot be considered in the same light as desertion, nor can unrest in a prisoner-of-war camp be assimilated to mutiny in the armed forces.”Footnote ¹⁷⁴ During the conference of government experts, the International Committee of the Red Cross (ICRC) had inquired whether offences that implied allegiance to the detaining power should be included as exceptions in special rules of the convention, as was the case for escape attempts. The idea was considered to be extreme, and, instead, the commission decided to include a stipulation “to remind the court that enemy P[O]W[s] brought before it for judgment are not nationals of the country, but that they owe obedience to the home country,”Footnote ¹⁷⁵ which can now be found in the relevant articles of Geneva Convention III. Footnote ¹⁷⁶

This fact draws one’s attention back to the discussion on contextual interpretation and the criticism of Ka Ho that was previously mentioned. There is no question that the discussions mentioned in the previous paragraph assumed that POWs are not nationals of the detaining power and, thus, owe it no allegiance. The question that arises is whether that assumption is generally applicable to all aspects of POW law or if it is an assumption solely included for the purposes of rules concerning procedures and penalties applicable to POWs. Note should be taken of the fact that the chapeau of the quoted extract clearly locates this assumption as a principle that governs the clauses on proceedings and sentences. The fact that the chapeau limits the application of this rule to proceedings and sentences begs the question of why the principle is not mentioned in the discussions of other areas, especially the provisions on POW status during the preparatory works of the convention. This could be argued to be an indicator of its restrictive application to proceedings and sentences exclusively and not of a more general underlying assumption.

After considering the interpretative process under the VCLT, it seems that there are no conclusive elements that would convincingly justify departing from a literal interpretation of Article 4 of Geneva Convention III. The formulation of Articles 87 and 100, providing that a POW does not owe allegiance to the detaining power, is unquestionably applicable to procedures and penalties; however, its existence as a general principle of POW status is not clear and, thus, cannot be argued unequivocally as a decisive contextual element. For its part, a teleological approach to interpretation and the practice related to it seem to favour the literal interpretation. Finally, there are important elements in the drafting history of Geneva Convention III, but, since they refer to Articles 87 and 100, it is not clear whether these elements can be extended to general rules regarding POW status and, more importantly, to an exception to POW status. It is true that a majority of scholarly opinions support the denial theory, but the previous section has shown that secondary sources are divided and do not reflect widespread practice.

subsequent state practice

Some authors have argued that the denial theory originates from state practice subsequent to the 1949 Geneva Conventions. This was the case for Yoram Dinstein, who once affirmed that non-allegiance to the detaining power is a condition for POW status that “is not specifically mentioned in the Geneva Conventions, and is derived from the case law.”Footnote ¹⁷⁷ The derivation of a requirement not included in the text of a convention refers either to the creation of a rule of customary international law, which has been shown earlier in this article to be highly questionable, or to subsequent practice as “objective evidence of the understanding of the Parties”Footnote ¹⁷⁸ in accordance with Article 31(3)(b) of the VCLT. Footnote ¹⁷⁹

Dinstein’s slight change of language in the most recent edition of his book comes as no surprise considering that the case law he once referred to was, in reality, only a single domestic judicial decision (the Koi case). Nonetheless, his point is interesting as it is reminiscent of the work of Georg Nolte as special rapporteur of the International Law Commission (ILC) on the topic of subsequent practice in relation to the interpretation of treaties. Although finding that the qualities of concordance, commonality, and consistency are not a minimum threshold for the applicability of Article 31(3)(b), Nolte affirms that these qualities are “an indication as to the circumstances under which subsequent practice under Article 31(3)(b) would have more or less value as a means of interpretation in a process of interpretation,”Footnote ¹⁸⁰ particularly when they allow one to identify a pattern of conduct that implies an agreement of the parties that must be included, through interpretation, as part of the treaty.Footnote ¹⁸¹ Evidently, the inclusion of the denial theory in the 2015 US military manual may be relevant in this sense, but it has insufficient weight or value on its own to determine the existence of an agreement to interpret Geneva Convention III as requiring non-allegiance or non-nationality for POW status. Further state practice clearly adopting this theory would be necessary, and, until that is evident, the Privy Council’s decision as well as the US military manual are only steps in the direction of the denial theory; they would have to be confirmed and reaffirmed by additional state practice through time.

Having said this, the most important question that arises here is whether including such a requirement (non-allegiance) would go beyond interpretation of Geneva Convention III and actually modify it. One of the conclusions reached by Nolte is that “[i]t is presumed that the parties to a treaty, by a subsequent agreement or subsequent practice, intend to interpret the treaty, not to modify it. The possibility of modifying a treaty by subsequent practice of the parties has not been generally recognized.”Footnote ¹⁸² It is evident that the incorporation of non-allegiance as a requirement of POW status, based on subsequent practice, would more than interpret the convention but would effectively modify Article 4 of Geneva Convention III by creating a further exception to the entitlement to POW status. The creation of such an exception via practice would amount to new customary law, and, therefore, the requirements of state practice and opinio juris would have to be met, including widespread, uniform, and consistent state practice. In the opinion of this author, Dinstein’s argument is far too generous since a single domestic case (the Koi case) cannot create a non-allegiance requirement by itself, nor can the Privy Council’s deductions be said to have led to a full reinterpretation of Geneva Convention III by states in this sense.

criticism of the denial theory

Before jumping to criticisms, it must be recognized that the denial theory is built upon two absolutely valid legal ideas. The first is the underlying idea that POW status is not automatically granted to all participants in an IAC that covers them with full, blanket immunity. It is clear from the provisions of IHL regarding POWs that certain requirements have to be metFootnote ¹⁸³ and that not everyone fulfilling them is entitled to POW status.Footnote ¹⁸⁴ The second idea is that being a member of an enemy army does not shield the individual from all punishment by his captors, and, thus, even fully covered POWs may be tried by the detaining state for domestic crimes.Footnote ¹⁸⁵ Despite this observation, it is impossible to ignore the fact that the denial theory poses a clash between domestic law and international law and, more importantly, that the denial theory refers to a very particular topic: the determination of POW status. Therefore, it is necessary to distinguish between arguments of domestic law and the whole body of international law concerning POWs. One of the most important criticisms that can be formulated against the denial theory is that it uses domestic law to alter the application of international law. This goes against the rule of international law that forbids states from relying on domestic law to breach their international obligations. The Permanent Court of International Justice (PCIJ) in its advisory opinion on the Treatment of Polish Nationals clearly affirmed that “a State cannot adduce as against another State its own Constitution with a view to evading obligations incumbent upon it under international law or treaties in force.”Footnote ¹⁸⁶ The rule has been characterized by the PCIJ as a generally accepted principle of international law,Footnote ¹⁸⁷ and it was incorporated in Article 27 of the VCLT. Footnote ¹⁸⁸ From that perspective, the denial theory would be in violation of a general principle of international law since it uses allegiance, which is nothing but a concept of domestic law, to avoid the application of Article 4 of Geneva Convention III, which grants POW status irrespective of nationality.

Beyond this remark regarding the dynamics of domestic and international law, a more specific criticism can be raised with reference to the sources usually quoted to justify the denial theory. As shown above, authors supporting the denial theory often use the writing of scholars — particularly Oppenheim — and, more recently, the Koi case as evidence of state practice. Unquestionably, the Koi decision represents a very interesting precedent since the Koi judgment is more recent and perhaps more specific to the issue under analysis than other cases such as those from the Second World War. However, scholarly references to the Koi case tend to present it superficially by focusing attention on the final decision adopting the denial theory. Such a treatment of the case disregards elements of the decision that cast strong doubts on its reliability. Upon a deeper reading of the case, two problems become evident: first, its reliance on Oppenheim’s opinion and, second, the factual findings of the case.

The Koi decision refers to Oppenheim’s opinion as evidence of “commonly accepted international law” and affirms that the edition quoted was published after the adoption of the Geneva Conventions and “in their Lordships’ opinion correctly states the relevant law.”Footnote ¹⁸⁹ In reality, Oppenheim’s opinion does not provide express evidence of state practice on this particular issue and, instead, only seems to reference his own work on how the flag of truce does not cover deserters as well as the writings of William Hall on the same issue.Footnote ¹⁹⁰ As argued above, the rule on parlamentaires that Oppenheim references is rather obscure and is not reflected in recent, known state practice and scholarly writings.

An additional criticism that can be raised against Oppenheim’s conclusion is that the denial theory derives from the no longer sustainable assumption that states reject the conferral of immunities on their own nationals or allegiants. The contrary is actually recognized in at least one area of contemporary public international law. As Ian Brownlie has pointed out, “[t]he Vienna Convention on Diplomatic Relations restricts the conferral of privileges and immunities in the case of members of the mission if they are nationals of the receiving State or ‘permanently resident’ therein.”Footnote ¹⁹¹ The extension to permanent residents shows that nationality alone is not the only concept that supports such a position. However, the commentaries of the ILC to the draft predecessor to Article 38 of the Vienna Convention on Diplomatic Relations noted that “practice is not uniform, and the opinion of writers is also divided.”Footnote ¹⁹² The division seems to have been between those who believed that even nationals of the receiving state should enjoy full privileges and immunities and those who believed that these individuals should only enjoy those expressly granted by the receiving state. The commentaries clarify that the majority of ILC members favoured an intermediate position granting the individual “a minimum of immunity to enable him to perform his duties satisfactorily. That minimum, it was felt, was inviolability, and also immunity from jurisdiction in respect of official acts performed in the exercise of his functions.”Footnote ¹⁹³ As Eileen Denza affirms, during the Vienna Conference, the ILC presented a compromise that was accepted by the delegations, including those initially opposed to granting nationals of the receiving state immunity as diplomatic agents because “a minimum of inviolability and immunity for official acts of such persons must follow as [a] logical consequence.”Footnote ¹⁹⁴ This precedent is of the utmost importance because it shows a functional approach that privileges the official operation of international relations over the domestic relations between states and individuals.

Following that, it could be argued that diplomatic and consular immunities may serve as a guide on how to solve the conflict between domestic entitlements of states and international rules conferring privileges on individuals who act in official capacities. Consequently, a parallel could be drawn between both areas of law (diplomatic and military). Nothing in international law impedes states from engaging, within their diplomatic or military ranks, nationals or permanent residents of another state. Both capacities (diplomatic and military) are covered by a special regime of international law that grants privileges and immunities. Such privileges imply that violations of domestic laws of the receiving state are covered. It follows that the international order takes priority for the purposes of ensuring the smooth operation of international norms and relations and, therefore, that those individuals enjoy a minimum degree of immunity when performing their official functions. This would seem to cover soldiers with POW status for all acts considered lawful under international law regarding the conduct of hostilities, even if such participation constitutes a criminal offence at the domestic level. One could argue the existence of a functional approach in international law by which state agents enjoy a minimum of immunity that allows them to exercise their official functions, even if they are nationals of the receiving state (or, for IHL purposes, the capturing state).Footnote ¹⁹⁵

But returning to the heavy reliance on Oppenheim’s opinion, there is yet another feature worth criticizing. During the Koi proceedings, some defendants raised the existence of contrary US jurisprudence (that is, the In Re Territo case) in order to show equal treatment of captured combatants despite nationality. However, the Privy Council dismissed the entirety of the US case on the basis that such a decision was based on “various authorities which do not support the contention that the particular protection relied on by the majority of the appellants extends to nationals of the Detaining Power who fall into that Power’s hands.”Footnote ¹⁹⁶ After an examination of the sources in question, it becomes evident that the erroneously referenced authority is the work of Oppenheim, who, as seen above, had a very clear position denying POW status to individuals owing allegiance to captor states. The mistake of the In re Territo court in referencing Oppenheim is undeniable. However, it is questionable to what extent the misquotation enables a court to dismiss the entirety of the In re Territo reasoning as flawed, particularly when — unlike the Privy Council in Koi — the US court actually did reference state practice conferring POW status irrespective of nationality. In particular, the US court noted that “Irishmen, though then subjects of Great Britain, who had taken the oath of allegiance to the South African Republic during the Boer war, were treated as prisoners of war.”Footnote ¹⁹⁷ In sum, it seems that heavy reliance on Oppenheim was used by the Privy Council not only to avoid supporting its decision with references to state practice but also to summarily dismiss contrary state practice (both the practice quoted in the US decision and the decision itself, which also counts as state practice) as being erroneously based on authorities that do not support the position. All of these elements make the dependence on Oppenheim’s opinion problematic and raise doubts regarding the validity of the foundations of the Koi judgment itself.

Having said that, the most controversial aspect of the Koi case is the fact that the strong theoretical doctrine set up by the Privy Council was not supported by the factual findings made by the various judicial instances considering the case. In other words, the decision relied on a doctrine that deprives individuals of POW status on the basis of allegiance without having been able to determine the allegiance of the defendants. The Privy Council and all of the previous Malay judicial instances in the case failed to determine the nationality of the accused. The decision referred to the accused as “Chinese Malays either born or settled in Malaysia,” but it accepted that “in no case was it shown whether or not they were of Malaysian nationality.”Footnote ¹⁹⁸ Probably aware of this major weakness, the Privy Council extended its denial of POW status not only to nationals but also to individuals owing allegiance by affirming that “allegiance is the governing principle whether based on citizenship or not.”Footnote ¹⁹⁹ For this purpose, the Privy Council found English jurisprudence convenient and referenced Joyce v Director of Public Prosecutions Footnote ²⁰⁰ and Rex v Neumann Footnote ²⁰¹ as cases showing that allegiance is independent of nationality but derives from protection and, consequently, that nationality was irrelevant to the case. On the allegiance of the accused, the decision affirmed that “[w]hether the duty of allegiance exists or not is a question of fact in which a number of elements may be involved.”Footnote ²⁰² However, the Privy Council did not make any effort to determine the existence of any allegiance to Malaysia and, in a shocking paragraph, simply accepted that “[i]t was not proved that the accused were citizens of Malaysia nor that they owed allegiance to Malaysia, though in many cases there was evidence which, if the issue had directly arisen, might have suggested that they did; but further findings of fact would have been required to decide either question.”Footnote ²⁰³

The Privy Council did not clarify to which evidence it was referring, and, from the whole of the decision, the only apparent element seems to be the fact that the majority of the captured individuals “carried blue identity cards issued pursuant to the National Registration Regulations which, by regulation 5(2)(a), provide for the issue of ‘blue bordered cards with blue printing to citizens of the Federation of Malaya.’ One carried a red card appropriate to a non-citizen.”Footnote ²⁰⁴ Many questions arise as to why, if the legal authorities had knowledge of the existence of such cards, none of them used them as evidence of the nationality of most of the individuals or the residency status of the remaining one, which would have proved a duty of allegiance. Proper legal procedure would have determined whether the cards were indeed issued by Malaysian authorities or, for example, counterfeit documents provided by Indonesian forces to their soldiers as a ruse to evade capture in case of document control on the ground during escape behind enemy lines. Furthermore, the Privy Council affirmed that allegiance was the governing principle but, at the same time, unapologetically brushed off strong circumstantial evidence suggesting that the individuals in question could have actually belonged to Indonesian forces and thus owed allegiance to Indonesia through their service in the armed forces.Footnote ²⁰⁵ The court dismissed this evidence by affirming that “[t]here was nothing to show that the accused were protected prisoners of war or to raise a doubt whether they were or were not. The mere fact that they landed as part of the Indonesian armed forces did not raise a doubt.”Footnote ²⁰⁶

With these observations in mind, it is only logical to re-evaluate the weight given in academic circles to the Koi decision as it seems to be a judgment in which the court arbitrarily presumed the nationality and allegiance of the accused and discarded strong evidence suggesting that the individuals actually belonged to the Indonesian armed forces. The outcome of this highly irregular procedure was a failure to effectively determine the status of the individuals under IHL, a fact that Richard Baxter pointed out back in 1969 when affirming that “[t]he better view … is that a person who outwardly seems to meet the requirements of Article 4, but whose nationality or allegiance is in question, should be put before a competent tribunal under Article 5 and must until that time be treated as a prisoner of war.”Footnote ²⁰⁷ Despite its gravity, it is doubtful that this criticism alone will be considered sufficient to invalidate the doctrinal position and the set of legal principles set out in Koi regarding allegiance and POW status. After all, it would not be the first time that an arbitrary wartime decision lacking factual foundation was used to create a theory in international law.Footnote ²⁰⁸ Very often, states and scholars turn a blind eye to the technical injustice committed against an individual in favour of a decision that brings redress for a particular offence and that sets a precedent to cite when defending preferred doctrinal views. Unfortunately, this seems to be the case with the Koi decision, as many cite it blindly.

Finally, it is important to understand that at the heart of the denial theory lies the concept of allegiance. But if protection is granted irrespective of race, ethnicity, religion, or nationality, why should we accept the introduction of allegiance as a new factor of discrimination in IHL? Allegiance is a very particular concept of the common law that has no legal counterpart in other legal systems. Although most states would share the idea that the individual should not betray the state, the bottom line is that, in many states, it is not an independent legal concept but is instead dealt with in criminal law as an alternative to adopting a customary duty deriving from nationality, residency, naturalization or service. Allowing this concept to define the scope of IHL protections would enable one legal system to impose, via international law, its doctrines on other legal systems that have developed differently. Another cause for concern is the fact that the common law theory of allegiance is vague and has permitted the adoption of highly controversial decisions that may produce very problematic results.

For instance, some cases have used allegiance to condemn foreign residents for treason when joining or collaborating with invading or enemy forces, regardless of the fact that such forces were their own national forces.Footnote ²⁰⁹ Despite the existence of a nationality link to the enemy, such precedents have discarded those links, holding individuals accountable on the basis of a type of allegiance derived from residency. In another case, a foreigner was sentenced for the sole possession abroad of a British passport, as British authorities argued that holding a passport conferred a duty of allegiance to the issuing state that derived from the protection it grants.Footnote ²¹⁰ This presumption was adopted in disregard of other important elements of the case, such as the fact that the person in question was not a British subject; had obtained the passport under false pretences; and had only used it to move to Germany with his family and belongings. The decision disregarded other facts that could have indicated his true allegiance in favour of a formalistic approach in which he could only be free from UK allegiance had he formally surrendered his passport. These cases, which have become seminal precedents in the common law, could be considered red flags outside of that legal tradition and should be reason for concern by other states since similar problems could arise if allegiance is allowed to become the driving force behind entitlement to POW status.

criticism of the conferral theory as a mere judicial guarantee (soft conferral theory)

In general terms, the soft conferral theory is in line with the content of Article 85 of Geneva Convention III, which enables the capturing power to prosecute POWs: “Prisoners of war prosecuted under the laws of the Detaining Power for acts committed prior to capture shall retain, even if convicted, the benefits of the present Convention.”Footnote ²¹¹ This provision implies that the state may prosecute crimes committed prior to capture, but it is necessary to question whether the provision applies to all crimes or not. Pictet tried to resolve this question in his commentaries by affirming that the provision covers crimes under international law (genocide, war crimes, crimes against humanity)—as well as acts not connected to the state of war — that is, violations of domestic criminal law including offences against the interests of the detaining power. However, when it comes to domestic crimes, the issue becomes complex as a state could misuse the provision to charge a domestic offence in order to punish the individual’s participation in the armed conflict. Pictet clarified that the article does not cover “trying a prisoner of war for an act or an attitude which is punishable under the laws of the Detaining Power but would not have been a matter for prosecution in his country of origin.”Footnote ²¹² Based on this, his commentary adopts a dual criminality test and suggests looking at crimes included in extradition treaties since “[a]n act in respect of which there could be no extradition should not be punished by the Detaining Power.”Footnote ²¹³ But this is not useful for several reasons. First, there is no certainty on which crimes will be charged against these individuals. Common sense would suggest political crimes, particularly treason. However, practice has shown that, due to the high evidentiary threshold of some of these crimes, domestic authorities may prefer to charge individuals with other types of crimes that may or may not exist in the state for which the POW fights.Footnote ²¹⁴ Second, crimes such as treason are universally recognized but traditionally excluded from extradition treaties,Footnote ²¹⁵ covering not only purely political crimes against the existence and security of the state but also relative political crimes that include actions such as illegal possession of firearms or providing support to certain organizations.Footnote ²¹⁶ In this sense, Pictet’s commentaries lack depth and do not solve the root of the issue.

A better approach to the problem might be to address the question of prosecutable actions from the point of view of IHL. In other words, the key issue is to determine whether special status under international law (such as POW status) shields anyone from prosecution for certain offences. The answer to this question could be found in the concept of so-called combatant immunity. The general understanding behind combatant immunity is that soldiers engage in hostilities under sovereign authority “and are therefore exempt from the normal bonds of law as privileged combatants.”Footnote ²¹⁷ The idea of possessing an authorization to partake in armed conflict is acknowledged within the rules of IHL under the notion of combatant status, in opposition to other categories of individuals who engage without authorization.Footnote ²¹⁸ Attached to combatant status comes the privilege of immunity as suggested by numerous authorsFootnote ²¹⁹ and recognized in the Lieber Code Footnote ²²⁰ and the Trial of Wilhelm List and Others before the International Military Tribunal in Nuremberg.Footnote ²²¹ In the context of IHL, logic dictates that such authorization is provided by the state under whose flag the forces fight. Therefore, a defector may not have the authorization of his home state under domestic law to fight but, under international law, is authorized by a belligerent power to do so and thus is authorized and covered by combatant immunity.

Having said that, the fact that combatant immunity is not included as a concept in the text of the Geneva Conventions forces one to refer to case law and the writings of academics in an attempt to clarify the extent and scope of the concept. When reviewing the literature on the subject, it is fairly common to find very general terminology describing the acts covered by the immunity. Some authors describe the privilege as “a blanket immunity for … pre-capture warlike acts.”Footnote ²²² Others affirm that the privilege shields those entitled to POW status “from criminal prosecution for those warlike acts which do not violate the laws and customs of war but which might otherwise be common crimes under municipal law.”Footnote ²²³ In the Noriega case, a US District Court determined that the essential purpose of Geneva Convention III is to protect POWs from prosecution for acts customary in armed conflict but not “to provide immunity against prosecution for common crimes committed against the Detaining Power before the outbreak of military hostilities.”Footnote ²²⁴ In this particular case, it was found that drug trafficking and other drug-related offences were “activities which have no bearing on the conduct of battle or the defence of country,” and, therefore, they were excluded from the privilege.Footnote ²²⁵ Other authors define the privilege in more specific terms. Some include acts such as homicide, wounding, destroying property, and detaining individuals,Footnote ²²⁶ while others refer clearly to acts of participation in hostilities.Footnote ²²⁷ In sum, it seems that combatant immunity covers all warlike acts that are not contrary to the laws of armed conflict and that form part of the conduct of hostilities themselves.

The matter should not be viewed from the viewpoint of domestic criminal law alone, and the domestic criminal character of the action has to be set aside in favour of the international legal character of the armed conduct. This is due to the fact that IHL is the prevailing legal framework regulating the prosecution of POWs, and even though it recognizes the right for a state to try a POW, this cannot enable a state to bypass the most fundamental rules of IHL. Under normal circumstances, states recognize that combatant privilege covers actions as serious as homicide, grave injury, and deprivation of liberty because they are committed in the context of war. It would be absurd not to cover with the same privilege all acts that are materially required for a person’s participation in the conflict such as his physical presence behind enemy lines, his enlistment with enemy forces, his use of uniforms, and the possession of weapons during military activities –– that is, his defection.

The problem arises when the said actions go beyond normal acts of participation that may be prosecuted and not covered by combatant immunity. It is possible that an individual switching sides might commit a set of serious crimes beyond mere treason or the carrying of weapons. For instance, a defector may have killed a fellow soldier to be able to cross enemy lines and join the enemy. This problem has not been addressed yet in international law, and one risks speculation when trying to address it. An objective and independent determination on a case-by-case basis would be desirable not only to prevent normal acts of participation from being categorized as prosecutable domestic crimes but also to avoid transforming combatant immunity into a blanket immunity and giving carte blanche to individuals to purge all crimes by simply switching sides. Evidently, this is an area that requires further development in both practice and scholarly writings, but enough has been shown here to make the argument that the rationale behind the rule permitting states to prosecute POWs is not to allow them to criminalize their participation in the conflict. The soft conferral theory commits a grave error by not drawing a line when it comes to criminalized offences and when it overlooks the concept of combatant immunity. Such a position actually weakens POW status under IHL and potentially enables states to criminalize lawful conduct under IHL as long as judicial guarantees are provided. For this reason, this author rejects the soft conferral approach.