A TREATISE ON INTERNATIONAL LAW
By WILLIAM EDWARD HALL, M.A.
(Second Edition, Oxford at the Clarendon Press, 1884)
MEANS OF EXERCISING THE RIGHTS OF OFFENCE AND DEFENCE.
§ 176. THE rights of offence and defense possessed by a belligerent community are exercised through the instrumentality of armed forces, and by means of military and naval operations. The legal questions which present themselves with reference to the constitution of armed forces being necessarily distinct from those having reference to the manner in which such forces may act, the general subject of the law dealing with the rights of offence and defence is primarily divided into two heads, the first of which may be against conveniently divided, since though the principles which govern continental and maritime warfare are identical, the differences which exist in the external conditions under which the two are carried on lead to differences in the particular rules affecting the constitution of the forces employed.
§ 177. Hostilities on land are for the most part carried on by the regular army of a state. The characteristics of this force from a legal point of view may be said to be that it is a permanently organised body, so provided with external marks that it can be readily identified, and so under the efficient control of the state that an enemy possesses full guarantees for the observance by its members of the established usages of war. It is the instrument expressly provided for the conduct of hostilities, and expressly adapted to carry them on in a legal manner.
But belligerent acts are also performed by bodies of men less formally organised, and the legal position of some of those is not yet so defined as to be in all cases clear.
It has been seen that although all the subjects of a belligerent state were originally in fact, and still are theoretically, the enemies of the enemy state, a distinction has long been made, under the influence of humanity and convenience, between combatant and non-combatant individuals. The latter are not proper objects of violence; the former may be killed and made prisoners, but when captured they must be treated in a specified way. It is evident that the treatment which is accorded to the two classes respectively, and the distinctive privileges which they enjoy, being caused by the difference in their character, must have been conceded on the tacit understanding that the separation between them shall be maintained in good faith. Non-combatants are exempted from violence because they are harmless; combatants are given privileges in mitigation of the full rights of violence for the express reason that they hold themselves out as open enemies. If either class were able to claim the immunities belonging to the other without permanently losing those proper to itself, an enemy would have made concessions without securing any corresponding advantage. Non-combatants would not be harmless and combatants would not be known. Those persons only therefore can properly do belligerent acts and claim belligerent privileges on being captured who openly manifest their intention to be combatant; and a belligerent, before granting such privileges, has obviously the right to exact evidence of intention. In the case of an invading army the distinction is easily made. With the exception of surgeons and other persons, whose employments, though ancillary to war, are conventionally regarded as peaceful, all persons must be taken to be combatant. But in the case of defensive forces the legitimate demands of an invader tend to conflict with the unrestricted right of self-defence, which is possessed by the individual as a component part of the assailed community. It is impossible to push the doctrine that combatants and non-combatants must remain separate to its logical results when the duty and sentiment of patriotism, and the injury, which even in modern warfare is always suffered by private persons, combine to provoke outburst of popular resistance. Persons must sometimes be admitted to the privileges of soldiers who are not included in the regular army. At the same time the interests of invading belligerents lead them to reduce the range of privilege as much as possible. Naturally practice shows the marks of these opposing influences. It is confused and not a little uncertain.
The evidences of intention to form part of the combatant class, which belligerents have been in the habit of exacting, falls under the heads of –
1. The possession of an authorisation given by the sovereign.
2. The possession of a certain number of the external characteristics of regular soldiers.
§ 178. The rule that permission from the sovereign is the condition of legitimate warfare as a matter of historical fact sprang rather from the requirements of sovereignty than from those of the belligerent rights possessed by an enemy. When the notions involved in the idea of the modern state began to be formed, sovereigns in investing themselves with the exclusive right to make war, by implication kept to themselves the right of regulating the war when begun, and so refused to their subjects the power of attacking the common enemy when and how they pleased. Subjects acted simply as the agents of the sovereign. At first they were all agents. The want of fleets and sufficient armies compelled sovereigns to rely on the population at large; leave therefore was usually given in a general manner at the beginning of war, and the declaration that ‘we permit and give leave to all our subjects to take up arms against the above-named by sea and land,’ or the order to ‘courir sus’ upon all the subjects of the enemy rendered warfare permissible to every one who chose to undertake it. But as war became more systematic, offensive operations were necessarily conducted by the regular forces of the state; and in defence it was found, either that irregular levies plundered their fellow-countrymen without doing service against the enemy, or that the rising of an unarmed peasantry in despair was merely the signal for a massacre. The old forms of permission continued, but they ceased to have a natural meaning; and in the eighteenth century hostilities on land were in practice exercised only by persons furnished with a commission from their sovereign. Belligerents acting on the offensive were not slow to give to facts an interpretation in consonance with their interests; and although the right of taking up arms in its own defence with the permission of the sovereign might still be conceded in books to an invaded population, it became the habit to refuse the privileges of soldiers not only to all who acted without express orders from their government, but even to those who took up arms in obedience to express orders when those were not addressed to individuals as part of the regular forces of the state. The doctrine which was thus on the point of being fixed was however to a great extent broken down by the events of the French revolutionary and imperial wars. France, Prussia and Russia all called upon their people at different times to embody themselves in levies which until then had not been recognised as legitimate, and other states encouraged or permitted still more irregular risings. No doubt nations were little willing to accord to others the rights of defence which they used for themselves; but the change in the character of wars from being mere contests of princes, as they generally were in the eighteenth century, to becoming struggles between peoples, as they generally were in the beginning of the present century, left its trace upon opinion. Of the writers who more immediately succeeded the Napoleonic period De Martens appears to incline to the old doctrine; but Wheaton gives combatants privileges not only to the regular forces of a nation, but to ‘all others called out in its defence, or spontaneously defending themselves in case of urgent necessity, without any express authority for that purpose;’ and Kluber recognises XXXXXXX levies en masse, and thinks besides that inhabitants of a fortress in assisting in its defence act under an implied authorisation. Statements of this kind, made after the question of the permissibility of the employment of subjects otherwise than as regular soldiers had been brought forcibly to the attention of the world, have greater weight than those of earlier writers. For a long time it was not necessary for any state to declare itself on the subject. In 1863 however it fell to the lot of the United States to do so. In that year the ‘Instructions for the Government of Armies in the Field’ were issues, and the 51st article says that ‘if the people of that portion of an invaded country which is not yet occupied by the enemy, or of the whole country, at the approach of a hostile army, rise, under a duly authorised levy, en masse to resist the invader, they are now treated as public enemies, and if captured, are prisoners of war.’ In 1870 the Germans acted in a harsher spirit. Notwithstanding that a law was passed by the French Assembly in August of that year under which ‘citizens rising spontaneously in defence of the territory’ were ‘considered to form part of the national guard,’ provided that they were distinguished by one at least of the distinctive signs that corps, the Prussian government required that ‘every prisoner, in order to be treated as a prisoner of war, shall prove that he is a French soldier by showing that he been called out and borne on the lists of a militarily organised corps, by an order emanating from the legal authority and addressed to him personally.’ This requirement, though far less stringent than the demands made in the eighteenth century, has failed to commend itself to the minds of jurists; and the proceedings of the Brussels Conference give reason to hope that the conduct of the Prussian commanders may remain without imitators. The ninth article of the draft Declaration, as adopted, lays down only that corps of volunteers shall ‘have at their head a person responsible for his subordinates,’ and the tenth article declares that ‘the population of a territory, not occupied, which spontaneously takes up arms at the approach of an enemy in order to combat the invading force, without having had time to organise itself comfortably’ to certain other requirements of the preceding article, shall be considered as ‘belligerent if it respects the laws and customs of war.’ If the rules of war were settled in conformity with these proposals, which were approved of by the larger military powers, and to which objection was made by the delegates of the smaller states on the ground only that enough scope was not left by them for spontaneous effort, the doctrine of state authorisation would for all practical purposes disappear. In some cases a rising would be permitted without authorisation, whether express or implied; in all it would be implied if a responsible person, not necessarily a soldier, were found at the head of a body of men possessing certain of the external marks characteristic of regular forces. That the law should be settled in this sense is eminently to be wished. The requirement of a state authorisation is generally superfluous. It offers no guarantee for the observance of the usages of war that is not better given by other rules, which are in most cases necessary, and to the enforcement of which there is no objection. In the few cases where the requirement of authorisation would would independently it may be questioned whether its effect would not be distinctly bad. History does not suggest that sudden uprisings of a population in face of an advancing enemy will often occur; but when they do take place, the depth of the patriotic sentiment which must have inspired them, and their helplessness against an organised force, call rather for treatment of unusual leniency than for exceptional severity.
§ 179. The characteristics of regular soldiers which armed forces are required by belligerents to possess as the condition of being recognised as legitimate combatants, may be said to be, either together or separately, according to the circumstances of the case,–
1. The fact of acting in more or less organised bodies of considerable size.
2. The existence of a responsible chief.
3. The possession of a uniform, or of permanent distinguishing marks on the dress.
With these conditions, as with authorisation, the tendency of usage has of late been towards relaxation. According to De Martens, it was scarcely allowed in the eighteenth century that a militia force could claim the privileges of regular troops, although in its nature it is a permanently organised body and consequently rather more than satisfied the two first of the three requirements. There are certainly some cases which go as far as this. In 1742 the Austrians excluded the Bavarian militia from belligerent rights; and the capitulation of Quebec in 1759, by providing that the inhabitants who had borne arms should not be molested on the ground that ‘it is customary for the inhabitants of the colonies of both crowns to serve as militia,’ suggests that, apart from the special custom, they would not have been left to the mercy of the English general. The root of this indisposition to admit militia to be legitimate combatants was rather in military pride than in any doubt as to the sufficiency of the guarantees which they presented. Through prejudice inherited from feudal times and the era of mercenaries, soldiers thought a militia unworthy to share in privileges which were looked upon as the sign of the honourable character of the military calling, because its members were neither soldiers by profession, nor able to share in the larger operations of war which were the peculiar business of the latter. The same causes which shook the doctrine of the necessity of express authority during the revolutionary and Napoleonic wars could not but be fatal to a distinction founded on no more solid a basis than this; and accordingly from that time no doubt has been entertained as to the legitimacy in principle of militia and other imperfectly organised levies. Such questions as exist refer solely to the quantity and relative value of the marks by which the legal position of a force, not belonging to the army proper, can be ascertained.
Much attention was directed to the subject during the Franco-German war of 1870-1; and the occurrences which then happened, together with the discussions which took place at the Conference of Brussels, render it possible to come to a faire conclusion as to the characteristics which ought now to be accepted as entitling a force to be recognised as belligerent. In the course of the war bodies of irregulars called Francs Tireurs were formed in France, who acted independently, without a military officer at their head, and who were distinguished in respect of dress only by a blue blouse, a badge, and sometimes a cap. The Germans refused to consider them legitimate belligerents on the double ground that they were not embodied as part of the regular forces of the states, viz. as part of the army or of the Garde Mobile, and that the distinguishing marks on the dress were insufficient or removable. The blouse, it was said, was the common dress of the population, and the badge and cap could be taken off and hidden at will. It was demanded that the marks should be irremovable and distinguishable at rifle distance. Where bodies of men are small, are acting independently, and especially if they are not under the immediate orders either of a military officer or of a local notability, such as a mayor in certain countries, an administrative official of sufficient rank, or a landed proprietor of position, they depend solely upon their dress marks for their right to belligerent privileges, since it is solely through them that the enemy can ascertain their quality. It is clear therefore that such marks must be irremovable; but to ask for marks distinguishable at a long distance is to ask not only for a complete uniform, but for a conspicuous one. The essential points are that a man shall not be able to sink into the class of non-combatants as his convenience, and that when taken prisoner there shall be no doubt on the patent facts how he ought to be dealt with. For both these purposes irremovable marks, clearly distinguishable at a short distance, are amply sufficient. The question whether irregular levies must be under the general military command, whether in fact, as a matter not of authorisation but of the sufficiency of the guarantees which it can offer for proper behavior, a population has the right of spontaneous action in a moment of opportunity or emergency, was discussed at the Conference of Brussels. In the original draft Project of Convention it was made a condition of the possession of combatant rights that the persons claiming to have them should be under such command, and the representative of the Germany showed a strong desire to maintain the requirement. After a good deal of discussion however the paragraph containing the condition was modified, and though the powers represented at Brussels are not legally bound by the terms of the draft Declaration as ultimately settled, it would be difficult for the great military states to ignore the admissions made on their behalf, and to refuse to acknowledge bodies of men headed by any responsible person as being combatant, irrespectively of connection with the general military command, provided that, as a body, they conform to the rules of war, and that if in small numbers they are distinguishable by sufficient marks. If in large numbers the case is different. Large bodies, which do not possess the full marks of a militia, must belong to one of two categories. They must either form part of the permanent forces of a state, which from poverty or some other reason is unable to place them in the field properly uniformed, or perhaps officered, as in the instance of the Norwegian Landsturm, to which attention was directed at Brussels by the Swedish representative; or else they must consist in part of the unorganised population rising in arms spontaneously or otherwise in face of the invader. In neither case are dress marks required. In the first the dependence on military command is immediate, and affords sufficient guarantees. In the second, dress marks are from the nature of the case impossible; and to insist upon them would be to nullify the concession which, as was seen in the last section, the military powers are ready to make, if the conclusions arrived at in the Brussels Conference can be taken to any degree as indicating their views. Dress marks in the particular case are besides unnecessary. The fact that a large body is operating together sufficiently separates it as a mass from the non-combatant classes, and there can be no difficulty in supplying the individual members with certificates which would prove their combatant quality when captured singly or in small detachments. The possession of belligerent privileges in such cases hinges upon subordination to a responsible person, who by his local prominence, coupled with the fact that he is obeyed by a large force, shows that he can cause the laws of war to be observed, and that he can punish isolated infractions of them if necessary.
 Le Cry de la Guerre ouverte entre le Roi de France et l’Empéreur in the Papiers d’Etat du Cardinal de Granvelle, ii. 630; Dumont, vii. i, 323.
 For instance, Vattel says that in the eighteenth century the order to ‘courir sus’ was understood as meaning that persons and things belonging to the enemy were to be detained if they fell into the hands of those to whom the order was addressed, but that it gave no right of offensive action; liv. Iii. § 227.
 Vattel, liv. Iii. §223.
 De Martens, Précis, § 271. See the Proclamations of the Austrians on entering Provence in 1747 and Genoa in 1748 (Moaer, Versuch, ix. i. 232-6), of the French on landing in Newfoundland in 1762 (ib. 240), and of the French on entering Hanover in 1701 (Ann. Register for 1761, 278).
Jomini (Guerres de la Revolution, viii. 137) in speaking of execution, by Napoleon’s orders in 1796, of the magistrates of Pavia and the slaughter of the peasants who had endeavoured to defend the town, says that ‘le droit public modern avait jusqu’alots tiré une de démarcation positive entre le citoyen paisible et les troupes de la ligne, et les habitants qui penaient part aux hostilités sans faire partie de l’armée régulière, étaient traités comme des revoltés.
A proclamation issued by the commanders of the Russo-Austrian army in the Lower Valais in 1799 is of little interest with reference to the present point, because the invaders may have looked upon the population of the Lower Valaid as being in insurrection against the suzerainty of the Upper Valais; but it is sufficiently atrocious and curious to be worth quoting on its own account. The generals order ‘le people du bas Valais par la présente de poser les armes sans auoun délai,’ and declare that ‘se au mépris de notre proclamation…quelques uns d’entre vous sont trouvés les armes á la main, nous vous annonçons qu’ils seront sans grace passés au fil de l’épée, leurs avoirs confisqués, et leurs femmes et enfants meme ne seront pas epérgnés pour server d’exemple á tous les mutins. C’est, pourquoi, chrétiens frères, rentrez en vous memes, tournez enfin vos armes contre vos véritables ennemis, qui vous trompent en se disant vos amis; songez que votre derniére heure a sonné et qu’il dépend encore dans cet instant de vous choisir votre parti.’ Koch, Mém. De Massena, Piéces justificatives, iii. 475.
 De Martens, Précis, § 271; Wheaton, Elem. pt. iv. ch. ii. § 9; Kluber, § 267.
 Art. ii. of the French law mentioned provided that ‘sont considérés comme faisant partie de la garde nationale les citoyens qui se potent spontanément á la défense du territoire avec l’arme don’t ils peuvent disposer, et en pregnant un des signes distinctifs de cette garde qui les couvre de la garantie reconnue aux corps militaries constitués.’ Calvo, § 1800. Proclamation of the General commanding-in-chief transcribed from the German Recuiel Officiel, published at Versailles, in Delerot , Versailles pendant l’Occupation, 104. Part of a similar proclamation is quoted by Bluntschli, § 570, bis.
 The majority of the members of the Institute of International Law present at the Hague in 1875, by expressing their approval of the Russian project of a declaration upon the laws and customs of war as modified by the Brussels Conference, condemned the conduct of the Germans. Since then the Institute, in its Manuel des Lois de la Guerre sur Terre (art. 3), has declared to be part of the legitimate armed force of a state ‘les habitants du territoire non occupe qui, a l’approche de l’ennemi, prennent les armes spontanement et ouverte-ment pour combattre les troupes d’invasion, meme s’ils non human ou le temps de s’organiser.’
 Trécis, § 271.
 Moser, Versuch, ix. i. 268; Ann. Regist. for 1759, p. 247. By the capitulation of the French Troops in Canada in the ensuing year it is agreed that the militia ‘shall not be molested an account of their having carried arms.’ Ann. Regist. for 1760, p. 222.
 The case of the Ordenanza in Portugal was similar. It was an organised but ununiformed militia, which during the advance of Massena in 1810 was used by Lord Wellington to harass the communications of the French army. Massena issued an order that all who might be captured could be shot, on which the English general addressed a letter to the former stating that ‘ce que vous appellez “des paysans sans uniforme,” “des assassins et des voleurs de grand chemin,” sont l’Ordenanza du pays, qui comme j’ai déjà eu l’honneur de vous assurer sont des corps militaries commandés par des officiers, payés, et agissant sous les lois militaries. Il parait que vous exigez que ceux que jouiront des droits de la guerre soient revetus d’un uniforme; mais vous devez vous souvenir que vous meme avez augmenté la gloire de l’armée Francaise en commandant des soldats qui n’avaient pas d’uniforme.’ Wellington Despatches, vi. 464. “La lecon que Massena recut á cette occasion due général anglais ne saurait etre trop connue,’ remarks Lanfrey, Hist. de. Nap. i. v. 386.
 D’Angeberg, Nos. 375, 854; Parl. Papers, Miscell., No. i, 1875, 80, 122, 140; arts. 9 and 45 of the Project of Convention, and arts. 9 and 10 of the Project of Declaration of Brussels. See also American Instruct. § 49, 51-52; the French Manuel de Droit Int. á l’Usage &c., 30; and the Manual of the Inst. de Droit Int. art. 2.
M. Rolin Jacquemyns (La Guerre Actuelle and Second Essai sur la Guerre Franco-Allemande) and Mr. Droop (Papers read before the Juridical Soc. vol. iii. pt. xxi.) have examined the questions treated of in the above section.