Smlouva a obyčej v mezinárodním právu

The question of relation between the treaty and custom does not present a topic worth particular scientific attention there where the two institutions are not being confused. This does not only occur in Czechoslovak Doctrine of international law, but the reasons for such confusion imprint – in juristic works interpretation – on the functionality of the two institutions a content that is no longer in harmony with the development stage of the contemporary general international law and above all with its peremptory rules. The qualification of international custom as tacit treaty hitherto upheld in Czechoslovak writings of international jurists – is in respect of development essentially in accord with the international law prior to the Great October Socialist Revolution and the actual exposition of the relation between treaty and custom corresponds rather to the period when the coming Soviet power was confronted (also from the power aspect) with the imperialist international legal superstructure. This old conception is, therefore, incapable to express the nowadays indisputable normative reflection of the presence of the socialist social system within the class structure of the international community of states, in the content of its legal order – in the contemporary general international law. The question of the grounds of the origin and binding character of the customary law too little pursued by our juristic works is one of the main reasons for scientifically unfounded favouring of the international treaty to the detriment of international custom – of its functional importance in present day international law. This is in particular evident in the definition of peremptority of profiling rules of the contemporary general international law, their origin and reason for their binding character can not possibly be grasped by treaty form at all. Inapplicable, therefore, are also positivistic interpretations of the origin and binding character of customary law – the interpretation both by fiction of tacit treaty and by means of the so called “recognition” theory – at their time intentionally restricting attention to form which was to be complied with by rule makers, though from such mere form the content of unwritten law can not be known: or just in order to provide room to the positivistic doctrine for speculative deductions about the law as it should be. If it is impossible to elucidate the binding character of treaty rules without taking acount of material sources only sometimes (clausula rebus sic stantibus), then it is necessary to take acount of social and political circumstances – i. e. of material sources – attendant upon the origin of a rule of law and in abstractness expressed in the hypothesis of such rule, in the customary law always. This is indirectly but convincingly corroborated by the most refined of schools of legal formalism – the normativist school – declaring, namely, as a point of its programme material sources an unfit subject of interest of the international law theory, yet in the end the Very same school came to confess its inability to elucidate the origin and reasons for the binding character of international custom just by means of the formal sources of the law. The theoretical foundation for the exposition of the grounds of origin and binding character of international customary law – making use of the material sources of the law – was laid by the Anglo-Saxon law school and so by the school working currently with the instrument of custom even in the domestic field. Decisive for the school is not an a-priori form hypothetically set down by the international law, with which – according to the requirement of the doctrine – practice must comply to enable a customary rule to come into existence, but the very practice of the states is law constituting if it is also general (usus generalis) and if accompanied by awareness of necessity (opinio necessitatis), i. e. by the realisation of unfortunate consequences in the event of different procedure. The Anglo-Saxon interpretation of the grounds of the origin and binding character of the international customary law was adopted by authors of Soviet Doctrine of international law by stating (G. I. Tunkin) that for individual countries it is necessary to regard as binding rules that are recognised by the absolute majority of countries and governed by them, if among them are states of both systems, big powers included. Here the parallel appearing endeavour to bridge the existing dissension in the interpretation of the origin and binding character of international customary law led, however, in the end (most significantly in the instance of G. I. Tunkin) to emphasizing consensus and thereby – conformably to the positivistic school – to the qualification of the international customary law as unwritten treaty; from there is but a little step to absolute favouring of the written treaty against custom, if custom be so described as unwritten treaty. In the Czechoslovak juristic works the treaty is favoured too not only because it is accompanied by an explicit expression of will compared to the hypothetical tacit and moreover presumed expression of will in the instance of custom (whereby treaty character is assigned to custom), but also because written law is attributed a higher value as compared to unwritten law and written treaty rules owing to their precision are designated as more reliable for legal regulation among states, in particular of different systems. The misconception of the value approach is proved by the relation between the customary (i. e. unwritten) general international law as treated in this country on the one hand and its codification on the other which relation is considered to be determined by the principle lex posterior derogat priori. Actually codification does not override any prior generally valid custom regulation, since universality in the acceptance of a codification treaty is as a matter of principle not required for coming in force in the instance of codification. In particular it is impossible Ito split jus cogens by such codification treaty in two particular regulations – one acting among the treaty signatories, the other for the remaining relations, since thereby would be abolished the jus cogens itself which in general international law is invalid ab initio – as also worded in Art. 53 of the Vienna Convention on the Law of Treaties (1969). The purport of codification is, therefore, merely to provide the general international customary law with a binding interpretation otherwise taken care of in the first place by the doctrine. Regarding the rules with which a codification treaty contributes to international law developments, these are of particular validity so long until rendered generally valid by law-creating custom, to which quality the codification treaty could have given just the stabilising impuls, but not the very binding character of legal validity: the same result could be brought about by a universal adoption of the codification treaty which is practically unrealistic. It is therefore wrong to see in the codification primarily a formulation of new rules in written form as currently handed down in the Czechoslovak international law literature, a codification treaty serving in the first place the written exposition of the general international law, a quality not met by newly provided rules in such treaty. Favouring of the treaty on the grounds of its written character to the detriment of custom because of its unwritten form has in the Czechoslovak Doctrine of international law the most serious consequences possibly there where written statements acquire principles of international law in the acts of potentially universal international organisations. To them should allegedly belong the part of general international law or even of a “constitution” wherefrom the validity of concrete rules of the international law is derived, though the very acts of such organisations are but of a recommending nature and the principles contained therein are no rules of international law whatever, being just a generalising interpretation of concrete rules of this law.