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Commentary - Spies
    [p.561] Article 46 -- Spies

    [p.562] General remarks

    1765 Under the terms of Article 24 of the Hague Regulations, the employment of measures necessary for obtaining information about the enemy and the country are considered permissible. This information may often be obtained by methods which, if not always detected, are at least openly employed for this purpose: a listening post, aerial photography, surface exploration etc. However, despite enormous technical progress, particularly in the field of listening-in devices and aerial photography (satellites), these methods occasionally prove to be incapable of penetrating well guarded secrets. This is where espionage comes in, i.e., resorting to the secret agent, which is not prohibited by either written or customary international law applicable in case of armed conflict, though States are left free to punish spies who are acting against their interests. Thus in times of armed conflict a spy does not engage the international responsibility of the State which sends him.

    1766 Espionage in the true sense, whether it entails a civilian or a member of the armed forces acting in secret, (1) is traditionally distinguished from what was formerly known as "war treason", which takes place particularly, though not exclusively, when a civilian living in occupied territory gives information to the enemy of the occupying forces. (2) The "war traitor" violates the law of the occupier. As such, he commits a violation of the law which the Occupying Power is entitled to promulgate, (3) on the understanding that the latter shall, on its part, [p.563] act in accordance with the rules in force, particularly the 1907 Hague Regulations (Articles 42 -56) and the fourth Convention (particularly Articles 47 -78).

    1767 Paragraphs 1 and 2 of this article confirm the traditional rules on espionage by reaffirming the essential principles of these rules. The specific object of paragraphs 3 and 4 is to extend, for members of the armed forces, the application of these rules to occupied territory. As regards persons who are not members of the armed forces, they are entitled to the guarantees laid down in Section III of Part IV of the Protocol, particularly those of Article 75 ' (Fundamental guarantees) ' which, in the case of arrest, supplement the other guarantees already laid down in the fourth Convention. It is understood that the derogations contained in Article 5 continue to apply in occupied territory (Article 45 , paragraph 3, second sentence). As regards this matter, the same applies to a spy who is a member of the armed forces captured in the act.

    Paragraph 1 -- The sanction for espionage

    1768 This paragraph illustrates what has been termed the dialectics of espionage. As we have seen, resorting to this method of combat is not prohibited. Yet, despite ("notwithstanding") the other provisions of the Conventions and the Protocol, any member of the armed forces who is caught while he is engaged in espionage may be deprived of his prisoner-of-war status and punished. In law this appears contradictory. In fact, the Parties to the conflict are here given a means of defence against a particularly dangerous method of combat. (4) However, it is quite clear that this is not an obligation, but merely a power: "shall not have the right to the status of prisoner of war and may be treated as a spy". (5) Nevertheless, this does not mean that the corresponding provisions of the first and Second Conventions do not apply in full when a spy is wounded, sick or shipwrecked. Moreover, a spy who has been deprived of his prisoner-of-war status, like any other spy who is not a member of the armed forces, is a civilian protected by the fourth Convention, though Article 5 considerably reduces the guarantees in this particular case. Similarly it is on this point that other provisions of the Protocol contain substantial guarantees, particularly in Article 75 ' (Fundamental guarantees). ' In the territory of a Party to the conflict these guarantees are also assured to a protected person who is personally subject to a legitimate suspicion that he is engaged in an activity which endangers State security or if it is established that he is in fact engaged in such activities. The fourth Convention, Article 5 , paragraph 1, provides that such persons, who may also be spies or [p.564] persons suspected of espionage, are not entitled to claim such rights and privileges under that Convention as would, if exercised in the favour of such persons, be prejudicial to the security of the State, though it is understood that they are not deprived of the rights of fair and regular trial (paragraph 3). In occupied territory, in accordance with the same Article 5 , the spy may be deprived of his rights of communication, and this restriction is not removed by Article 75 ' (Fundamental guarantees) ' of the Protocol (see Article 45 -- ' protection of persons who have taken part in hostilities, ' paragraph 3).

    1769 Nevertheless, if a person suspected of espionage appears to be a member of the armed forces, (6) he should have the benefit of prisoner-of-war status as long as there is any doubt regarding the matter of his right to such status, and until a competent tribunal has decided on this matter (Article 45 -- ' Protection of persons who have taken part in hostilities, ' paragraph 1). In short, there may exist two conflicting presumptions simultaneously: prisoner of war or spy. The presumption of prisoner-of-war status should prevail, at any rate whenever the person concerned has not been charged on the basis of prima facie evidence. (7)

    1770 The deprivation of prisoner-of-war status already constitutes a punishment in itself and can therefore only take place following the tribunal's decision. (8) This applies a fortiori to the deprivation of prisoner-of-war treatment. Furthermore, the Conference did not intend to change the substance of the traditional rules of espionage adopted in The Hague, but merely sought to supplement and elaborate them. (9) This conclusion was confirmed by the wording of Article 39 ' (Emblems of nationality), ' paragraph 3, which refers to the "existing generally recognized rules of international law applicable to espionage".

    1771 Under the terms of the Hague Regulations, "a spy taken in the act shall not be punished without previous trial" (Article 30 ). Does this mean that the spy can only be punished as such if he is caught in the act? In fact, this is certainly the sense of the Regulations, as Article 31 provides that, "a spy who, after rejoining the army to which he belongs, is subsequently captured by the enemy, is treated as a prisoner of war, and incurs no responsibility for his previous acts of espionage". (10)

    [p.565] 1772 The text of the Protocol is equally explicit when it states in the present paragraph that, when a member of the armed forces falls into the power of an adverse Party "while engaging in espionage", (11) he "shall not have the right to the status of prisoner of war and may be treated as a spy".

    1773 As regards the tribunal, it is in no way obliged to take into account the motives of the accused, and may convict him equally whether he has acted from patriotic motives or for reasons of personal gain. (12) In many cases the tribunal will have to pronounce sentence merely on the basis of a presumption. The use of perfidious means such as the misuse of the flag of truce, the red cross emblem, signs, emblems or uniforms of the United Nations or of neutral or other States not Parties to the conflict, (13) can constitute an aggravating circumstance. This may also apply to the employment for purposes of espionage of medical aircraft, which under the terms of Article 28 ' (Restrictions on operations of medical aircraft), ' paragraph 2, "shall not be used to collect or transmit intelligence data and shall not carry any equipment intended for such purposes". (14)

    Paragraph 2 -- Definition of a spy (15)

    1774 In fact this paragraph does not give a definition of a spy. Moreover, some considered that such a definition does not belong in a text of humanitarian law. However, by giving a sufficiently precise description of those who shall not be considered as spies, it is possible to deduce the constitutive elements of espionage in any specific case, by means of a contrario reasoning. Supplemented by the provisions of paragraph 3, which relate to occupied territory, these elements do give, after all, the complete characteristics of the spy as he is defined in the Hague Regulations. (16) The resulting definition, without being fundamentally different, is nevertheless wider than that of the Regulations, and corresponds to that which is [p.566] found today in most military manuals. Strictly speaking, this paragraph corresponds to the second paragraph of Article 29 of the Hague Regulations, which also gives a description of those who shall not be considered as spies, though admittedly in a form which is in some respects rather outmoded. (17)

    1775 In the sense in which spies are generally understood today, the spy corresponds to the definition that was already given by Lieber: "a person who secretly, in disguise or under false pretence, (18) seeks information with the intention of communicating it to the enemy" (Article 88 ). It logically follows that anyone who seeks information while dressed in the uniform of his armed forces, cannot be a spy. But the expression "gathers or attempts to gather", which is used in the present paragraph, as it is with other words ("obtains or endeavours to obtain") in the definition of the Regulations, clearly shows that no distinction is made between the attempt and the successful operation. As regards the territorial field of application of the rule, there is no longer an intent to limit it to the area of operations. It covers all "territory controlled by an adverse Party": national or occupied territory, area of operations (on land, at sea, or in the air), including the territorial sea. In paragraph 2, the nature of the information is not defined, while paragraph 3, which deals with occupied territory, specifies that this should be "information of military value". This distinction in the wording is deliberate, as inhabitants of occupied territory should not be open to the accusation of espionage for no good reason. Thus it is up to each Party to the conflict to determine what information could fall under the scope of this paragraph. (19) However, in general, it is accepted that nowadays information can create a military advantage, even when it does not have a military character.

    1776 The problem of uniform is possibly an even more vexed question. (20) One delegate at a plenary meeting asked what significance it should be given "in the case of combatants who were not required to wear uniform, and who, in any case, had no chance of wearing one". (21) The question was by no means irrelevant, although it is understood that the word "uniform" applied not only to a uniform in the conventional sense, but to any distinguishing sign which warranted that the activity in question had nothing clandestine about it. In addition, the Rapporteur declared that this means that: "any customary uniform which clearly distinguished the member wearing it from a non-member [of the armed forces], should [p.567] suffice". (22) All the same, that does not alter the fact that certain categories of combatants can, as we have seen, (23) be exempt from all distinguishing signs with the exception of the open carrying of arms. (24) However, as the majority of delegations only seemed to be able to envisage such an eventuality in occupied territory, this problem will be examined in the context of paragraph 3. It should suffice here to remember that, in the view of several experts, the characteristic feature of the spy is not primarily the clandestine nature of his activities, for the search for information is often carried out at night or in order to avoid capture, observers camouflage themselves, etc. The spy employs pretence and deceit, and this, depending on the circumstances, could constitute an unlawful ruse of war or even an act of perfidy within the meaning of Article 37 ' (Prohibition of perfidy). '

    Paragraph 3 -- Occupied territory

    1777 At first sight the text of this paragraph seems to express a self-evident fact, i.e., that only a spy can be considered to be a spy in occupied territory, and then only if he is caught in the act. In reality the situation in occupied territory is complex, and the rules needed to be clarified. This provision covers only residents of occupied territory who are members of armed forces, and not the civilian population. (25) Paragraph 4 deals with the non-resident, so the concept of residence is common to paragraph 3 and paragraph 4. The Rapporteur states that the Working Group did not devote much attention to the question who will be considered to be a resident. A number of delegations would have preferred to add qualifications such as "usual" or "ordinary" to the word "resident" in order to exclude from the benefits of paragraph 3 any person sent to the occupied territory in order to engage in espionage. However, the Rapporteur points out that such a person can always claim to have been sent there to engage in hostile acts, and that in this case, it would be impossible to furnish the proof. (26) The fact remains that this paragraph concerns only residents, i.e., the inhabitants of occupied territory, whether nationals or not, who are properly entitled to live in [p.568] this territory either permanently or on a long-term and ordinary basis, (27) which corresponds with the concept of ordinary residence. (28)

    ' First sentence -- Definition of the spy who is a resident of occupied territory '

    1778 The formulation of this provision is in many respects similar to the general definition of the spy given in Article 29 , paragraph 1, of the Hague Regulations. This is primarily because of the negative turn of phrase which gives the provision a restrictive scope. It should also be noted that the territorial field of application of the rule is precisely circumscribed as it refers only to occupied territory. Finally, it does not contain any mention of uniform or the absence of uniform (obviously a spy could attempt to carry out his activities under cover of the uniform of the adverse Party) but refers to the fact that he is acting under "false pretences or deliberately in a clandestine manner". This expression is virtually identical to the text of the Hague Regulations. As stated above, the information which falls under the prohibition is specified here, whereas it is not specified in paragraph 2: it is information of military value. (29)

    1779 Now this is the crux of the matter: though the person concerned, a member of the armed forces, gathers or attempts to gather information of a military nature, he need not necessarily be a spy, even when he is not wearing a uniform. In other words, the absence of uniform or what takes the place of uniform, is not automatically equivalent to an activity undertaken "through an act of false pretences or deliberately in a clandestine manner", (30) since in certain situations which arise particularly or exclusively in occupied territory, guerrilla combatants are expressly exempt from the obligation to distinguish themselves from the civilian population (Article 44 -- ' Combatants and prisoners of war, ' paragraph 3). Admittedly such combatants are obliged to carry their arms openly in combat and preparatory to combat, and they are perfectly capable of attempting to gather information while carrying their arms openly. They are then excluded from being considered as spies. However, apart from this situation, residents who are members of armed forces

    "will almost necessarily in their everyday life come across information of value to the armed forces to which they belong, and this should not make [p.569] them spies or serve as a pretext for denying them protection as prisoners of war. On the other hand, it was agreed that, if they disguised themselves in order to gain access to secret information or in other ways used false pretences or deliberate clandestine acts in order to obtain such information, they would be spies. For example, the resident who observes military movements while walking along the street or who takes photographs from his residence would not be engaged in espionage; whereas the resident who uses a forged pass to enter a military base or who, if lawfully on the base, illegally brings a camera with him, would be engaging in espionage". (31)

    ' Second sentence -- Sanction for espionage in occupied territory '

    1780 The analysis of paragraph 1 revealed that the spy who rejoins the army to which he belongs does not incur any responsibility for his previous acts of espionage if he is captured by the enemy later. For a member of the armed forces who is resident in occupied territory, there is no such possibility of actually escaping from the power of the adverse Party, and thus of setting aside the jurisdiction of the latter in the matter of espionage. Does this then mean that if he is captured, a member of the armed forces who is a resident of occupied territory and who has committed an act of espionage, loses all his rights to prisoner-of-war status until hostilities cease? This is not the case, and this provision gives the appropriate guarantees.

    1781 It is in fact only insofar as he is captured in the act of espionage, that the spy who is a resident of occupied territory loses his right to prisoner-of-war status. This condition is rendered here by the expression "unless he is captured while engaging in espionage". It follows that "the spy who is a resident of occupied territory may be considered as rejoining his forces whenever he ceases to engage in espionage". (32) In this context the Rapporteur adds that:

    Although no attempt has been made by the Working Group to define more precisely when a resident may be considered as engaging in espionage, several delegates suggested that each act of espionage would end when the information obtained had been transmitted by the spy to his armed forces. (33) This approach was commended, as it would reduce the possibility that an Occupying Power could improperly deprive captured members of underground armed forces of their rights to be prisoners of war by asserting that they were captured while engaging in espionage." (34)

    Finally, the considerations relating to Article 46 , paragraph 1, apply a fortiori in occupied territory.

    [p.570] Paragraph 4 -- Espionage in occupied territory by a non-resident

    1782 In the case of espionage in occupied territory by a member of the armed forces who is not a resident of this territory, the rule contained in this paragraph corresponds to that of Article 31 of the Hague Regulations. Thus a spy loses his right to the status of prisoner of war and may be treated as a spy only if he is captured before rejoining the armed forces to which he belongs. This condition will not be deemed to be fulfilled whenever the spy succeeds in leaving the occupied territory and regaining either the territory of the Power to which he belongs or that of an Allied Power, or neutral territory. If he rejoins within occupied territory the clause implies the presence, if only temporarily, of adverse armed forces organized in accordance with Article 43 ' (Armed forces), ' whether they consist of a commando raid, a mobile column, a reconnaissance unit or a forceful search operation. Such operations do not have the effect of changing the status of the territory in which they take place, which consequently remains occupied territory subject to the jurisdiction of the Occupying Power. However, the armed forces which carry out such operations assure the spy who rejoins them the safeguards provided for in this paragraph.

    1783 In addition, reference should be made to the commentary on paragraphs 1and 3 above.


    1784-- Only someone who gathers or attempts to gather information through an act of false pretences or deliberately in a clandestine manner, with the intention of transmitting it to the enemy, shall be considered as a spy.

    1785-- The spy captured in the act does not have the right to prisoner-of-war status.

    1786-- The spy captured after rejoining his armed forces is a prisoner of war. A resident of occupied territory who is captured, but not whilst engaging in espionage, should also be considered as a prisoner of war.

    1787-- The spy who is denied the status of prisoner of war is a civilian protected by the fourth Convention (except that in occupied territory may lose his rights of communication (Article 5 )), and by Article 75 ' (Fundamental Guarantees) ' of the Protocol.

    1788-- In cases of doubt, the person concerned is treated as a prisoner of war pending a decision regarding his status by a competent tribunal. Penal sanctions can only be imposed by a judicial tribunal.

    ' J. de P. '


    (1) [(1) p.562] On this concept, see infra, paras. 2 and 3;

    (2) [(2) p.562] War treason also includes all acts of sabotage and collaboration with the enemy when they are committed by persons resident in occupied territory who are not members of the armed forces, such as: the destruction of means of communication, assistance to prisoners of war who are escaping, propaganda favourable to the adversary, furnishing the latter with means of transport, abusing the function of a guide for the purpose of misleading occupying troops etc.;

    (3) [(3) p.562] Cf. Fourth Convention, Articles 5, 64 (paragraph 2), 68. As regards nationals of a Party to the conflict who engage in acts of espionage for the benefit of the enemy, they are generally accused of high treason and are subject to national law (on the applicability of the guarantees of Article 75, see the commentary on that article). This is without prejudice to provisions of human rights legislation;

    (4) [(4) p.563] Cf. F. Lieber, op. cit.: "While deception in war is admitted as a just and necessary means of hostility, and is consistent with honourable warfare, the common law of war allows even capital punishment for clandestine or treacherous attempts to injure an enemy, because they are so dangerous, and it is difficult to guard against them" (Article 101);

    (5) [(5) p.563] It will be noted that this expression"shall not have the right"is also used in Article 47 ("shall not have the right to be a combatant or a prisoner of war") with regard to mercenaries; Article 44, paragraph 4, deals with the case in which a combatant "shall forfeit his right to be a prisoner of war, but he shall, nevertheless, be given protections equivalent in all respects";

    (6) [(6) p.564] See supra, ad Art. 45, para. 1, p. 546;

    (7) [(7) p.564] This solution does not affect security measures which the Detaining Power might consider to be necessary "for reasons of imperative military necessity", whether this concerns supervision (Third Convention, Art. 126, para. 2), correspondence (Art. 76, para. 3), or trial ' in camera ' (Art. 105, para. 5). Such derogations should be as short as possible. The problem of the "capture card" (Art. 70) is more delicate, even though it is not obligatory, but the prisoner must be registered (Art. 122);

    (8) [(8) p.564] Moreover, there may be justifiable concern to avoid abuses during periods of psychological tension which are characteristic of armed conflict, favouring what could be called "spy mania", i.e., the fact of considering any foreigner to be a spy without a valid reason, or on the flimsiest pretext. Moreover, Art. 44, paragraph 3, increases the risk of confusion. It has even happened that escaped prisoners of war have been considered to be spies;

    (9) [(9) p.564] See O.R. XV, p. 99, CDDH/III/SR.47, para. 80, and p. 430, CDDH/III/338;

    (10) [(10) p.564] The analogy with Article 91 of the Third Convention should be noted. It provides that prisoners of war who have made good their escape and who are recaptured shall not be liable to any punishment in respect of their previous escape. However, this immunity does not extend to violations committed during the escape, if these are not linked with the escape, or if they entailed violence against persons (Art. 93, para. 2);

    (11) [(11) p.565] According to Mechelynck, and the deliberations which took place in The Hague, Article 31 of the Regulations does not only apply to members of the armed forces, but also to civilians. The inhabitant of an area which is not occupied, who seeks information in the enemy's area of operations and returns to his own area after completing his mission, may not be prosecuted if his area falls into the hands of the enemy at a later date (A. Mechelynck, op. cit., p. 302). As regards Article 30, this protects the inhabitant of occupied territory on the same basis as any other person arrested as a spy (ibid., p. 299);

    (12) [(12) p.565] A. Mechelynck, op. cit., p. 294;

    (13) [(13) p.565] Cf. Art. 37, para. 1(a) and (d), and Art. 85, para. 3(f);

    (14) [(14) p.565] On the general problem of medical confidentiality, see commentary Art. 16, para. 3, supra, p. 204;

    (15) [(15) p.565] Article 40 of the ICRC draft was worded as follows: "1. Members of armed forces in uniform and other combatants referred to in Article 4 of the Third Convention, as well as those combatants referred to in Article 42 who, in their operations, distinguish themselves from the civilian population and who, having entered enemy-controlled territory or having remained therein, gather or attempt to gather military information for further transmission shall not be considered as spies";

    (16) [(16) p.565] The spy is defined there in a negative and restrictive form: "A person can only be considered a spy when, acting clandestinely or on false pretences, he obtains or endeavours to obtain information, in the zone of operations of a belligerent, with the intention of communicating it to the hostile party" (Art. 29, para. 1);

    (17) [(17) p.566] "Thus, soldiers not wearing a disguise who have penetrated into the zone of operations of the hostile army, for the purpose of obtaining information, are not considered spies. Similarly, the following are not considered spies: soldiers and civilians, carrying out their mission openly, entrusted with the delivery of despatches intended either for their own army or for the enemy's army. To this class belong likewise persons sent in balloons for the purpose of carrying despatches and, generally, of maintaining communications between the different parts of an army or a territory";

    (18) [(18) p.566] Paragraph 3, using a similar wording to the Hague Regulations on this point (Art. 29), uses the expression"through an act of false pretences or deliberately in a clandestine manner";

    (19) [(19) p.566] Thus Article 86 of the Swiss military penal code incriminates anyone who has spied on facts, dispositions, procedures or objects which are kept secret in the interests of national defence in order to pass them or make them accessible to a foreign State, one of its agents, or the public;

    (20) [(20) p.566] On this point see also supra, ad Art. 39, para. 3, p. 469;

    (21) [(21) p.566] O.R. VI,p. 111, CDDH /SR.39, para. 115;

    (22) [(22) p.567] Ibid., para. 116, and O.R. XV, p. 388. CDDH/236/Rev.1, para. 35, and supra, commentary Art. 39, para. 2, p. 468;

    (23) [(23) p.567] Supra, ad Art. 44, para. 3, p. 527;

    (24) [(24) p.567] One delegation claimed in the Working Group that this was a false problem, as the fact that a spy is wearing purely civilian dress does not constitute a threat for the civilian population, since the spy has no intention of opening fire and may not even be armed;

    (25) [(25) p.567] According to the Hague Regulations, the situation of an inhabitant of occupied territory was more or less similar to that of a prisoner on parole. He sees everything that happens, but this does not authorize him to reveal it (in this respect, see A. Mechelynck, op. cit., pp. 262-263). However, it should be mentioned that the population of occupied territory owes no allegiance to the Occupying Power (Fourth Convention, Art. 68 ). See also supra, note 11. In addition, Art. 31 of the Fourth Convention states that "no physical or moral coercion shall be exercised against protected persons, in particular to obtain information from them or from third parties". On the other hand, the Occupying Power may subject the population of the occupied territory to provisions which are essential to ensure its security (Fourth Convention, Art. 64, para. 2);

    (26) [(26) p.567] O.R. XV, p. 431, CDDH/III/338;

    (27) [(27) p.568] However, one delegation wished to make a statement to the effect that the term "resident" should be understood to include persons who had had to leave the territory as a result of excesses on the part of the Occupying Power as well as persons evacuated by the occupying authorities (see O.R. XV, p. 93, CDDH/III/SR.47, para. 46);

    (28) [(28) p.568] Cf. the advisory opinion of the Permanent Court of International Justice of 21 February 1925 on the exchange of Greek and Turkish populations where the concept of "établissement" was considered to include two factors: residence and stability (W. Benedek,"Exchange of Greek and Turkish populations (Advisory opinion)", in Bernhardt (ed.), op. cit., Instalment 2, p. 92;

    (29) [(29) p.568] It is understood that information which is not of a military nature, but, for example, economic or political, can be of military value;

    (30) [(30) p.568] Cf. the remark of one delegation: "A member of a liberation or resistance movement would not be considered to be acting under false pretences simply because he was wearing civilian clothing" (O.R. XV, p. 93, CDDH/III/SR.47, para. 46);

    (31) [(31) p.569] Rapporteur's Report, O.R. XV, p. 430, CDDH/III/338;

    (32) [(32) p.569] O.R. XV, pp. 430-431, CDDH/III/338;

    (33) [(33) p.569] Cf. the statement of a delegation at a plenary meeting, that the formula"while engaging in espionage" includes all the stages of the act of espionage until the completion of the transmission of the information to the enemy (O.R. VI, p. 116, CDDH/SR.39);

    (34) [(34) p.569] O.R. XV, p. 431, CDDH/III/338;