le fonti del diritto internazionale


le fonti del diritto internazionale
---Diritto internazionale (A-L)
Corso del Prof. Attila Massimiliano Tanzi
A.A. 2014-2015
«1. The Court, whose function is to decide in accordance with international law
such disputes as are submitted to it, shall apply:
a) international conventions, whether general or particular, establishing rules
expressely recognised by the contesting States;
b) international custom, as evidence of a general practice accepted as law;
c) the general principles of law recognised by civilised nations;
d) [...] judicial decisions and the teachings of the most highly qualified
publicists of the various nations, as subsidiary means for the determination
of rules of law.
2. This provision shall not prejudice the power of the Court to decide a case ex
aequo et bono, if the parties agree thereto»
Statute of the International Court of Justice, Art. 38
Fonti formali (o «tipiche»):
• Gli accordi internazionali (che verranno discussi la prossima settimana);
• Le consuetudini;
• I principi generali del diritto (tra cui l’equità).
Fonti atipiche:
• Gli atti unilaterali;
• Gli atti di soft law.
Nessuna gerarchia formale
«Il faut se rappeler que le droit se développe entre deux extrêmes: la rigueur et la flexibilité. La
rigueur doit garantir la stabilité du droit dans le sens que les cas systématiquement identiques
doivent être décidés de façon identique. Cette stabilité est une exigence de la justice systematique
(Systemgerechtigkeit). La flexibilité, c’est-à-dire l’adaptabilité du droit aux exigences du cas en question
est aussi un postulat de la justice du cas particulier (Fallgerechtigkeit)»
SCHWIND, Aspects et sens du droit international privé, in Recueil des cours, 1984-IV, p. 25
«Les règles normatives dans leur forme extérieure sont invariables comme les termes qui les
expriment. Mais ces formes ne sont que des capsules dont le contenu est variable sans qu’on s’en
aperçoive. La capsule reste invariée jusqu’au moment où le contenu a tellement changé que la
capsule éclate et on doit en trouver une autre qui s’adapte mieux à la fonction changée»
Ibidem, p. 125
• Formazione in base al consenso degli Stati;
• Assenza di un «legislatore internazionale»;
• Revisione della teoria delle fonti nell’epoca della decolonizzazione:
• Consuetudine istantanea: «Recognition or acceptance by a state of a particular customary rule as a norm of law
signifies an expression of a state’s will, the consent of a state, to consider this customary rule to be a norm of
international law» (TUNKIN, Theory of International Law, Londra, 1974, p. 123)
• Convenzioni di codificazione: «[t]he General Assembly shall initiate studies and make recommendations for the
purpose of: […] a. promoting international co-operation in the political field and encouraging the progressive
development of international law and its codification [...]» (Charter of the United Nations, Art. 13).
«The augmented role of multilateral forums in devising, launching, refining and promoting general
international law has provided the international community with a more formal lawmaking process that is
used often. The increased clarity and the more transparent process encourage widespread participation and
endow the resulting law with greater legitimacy than is generally possible through the traditional customary
lawmaking process. The international community may establish international law that will bind every state
without exception. [...] Indeed, the current system offers all states an increased opportunity to participate in
that process, either at the relevant multilateral forum or shortly afterwards when reaction to the potential law
is timely. This newly evolving process further enables the international legal system to attend to universal
problems that increasingly require solutions in international law. They include threats to the peace, violations
of fundamental human rights and risks that could envelop all humankind by severely damaging the global
environment. [...] Solving these problems must not be thwarted by the objections or actions of few obstinate
CHARNEY, Universal International Law, in American Journal of International Law, 1993, pp. 529-551, p. 551
«Our actions, taken consistently with constitutional principles, require no separate external validation to make them legitimate. Whether it
is removing a rogue Iraqi regime and replacing it, preventing weapons of mass destruction proliferation, or protecting America against an
unaccountable court, the United States will utilize institutions of representative government, adhere to its constitutional structures, and
follow its values when measuring the legitimacy of its actions»
BOLTON, Address at The Federalist Society, 2003 National Lawyers Convention, 13 novembre 2003, reperibile sul sito www.fed-soc.org/pdf/bolton.pdf, pp. 19 ss.
«[...] the decentralized and unaccountable way in which “international law”, and particularly customary international law, is made. It is one
of those international law phenomena that just happens out there, among academics and activists [...]»
BOLTON, in BLIX, The Use of Force in the International Community, Hersch Lauterpacht Memorial Lectures, Cambridge, 22 novembre 2004, p. 7
«Many writers emphasize their antitethical features. Treaty law is identified as lex scripta, the result of a deliberate intellectual effort, as having the qualities of
precision, clarity, systematic order; while customary law is lex non scripta, described as spontaneous, unintentional, unconscious in its origin, disorderly,
uncertain in its form, slow in its establishment. Some writers even qualify it as a «procedé artisanal», not well adapted to the rapid pace of evolution in the
modern world.
Such an antithesis may be correct in the municipal field, where statutes and codes are rightly opposed to customary law, but it is not true in the international
sphere. Treaty law and customary law do not exist in sealed compartments in contemporary international law.
It has been recognized for a long time that rules of law formulated in the text of a treaty may at the same time constitute or become rules of customary
international law. What is important to emphasize is that this process of interaction between the two sources has acquired a greatly increased significance in
the contemporary world»
JIMÉNEZ DE ARÉCHAGA, Custom, in CASSESE, WEILER (eds.), Change and Stability in International Law-Making, Berlin-New York, 1988, pp. 1 ss.
Disciplinati in ogni aspetto da una convenzione di codificazione: la Convenzione di Vienna sul
diritto dei trattati del 1969 (1969 Vienna Convention on the Law of the Treaties, ‘VCLT’)
«47. In the first place, it is for the Court to interpret the provisions of a treaty in the present case. It will do
so in terms of customary international law on the subject, as reflected in Articles 31 and 32 of the 1969
Vienna Convention on the Law of Treaties, as the Court has stated on several occasions […].
Consequently, neither the circumstance that Nicaragua is not a party to the Vienna Convention on the Law
of Treaties nor the fact that the treaty which is to be interpreted here considerably pre-dates the drafting of
the said Convention has the effect of preventing the Court from referring to the principles of
interpretation set forth in Articles 31 and 32 of the Vienna Convention».
Dispute regarding Navigational and Related Rights (Costa Rica v. Nicaragua), in ICJ Reports, 2009, p. 237
Basati esclusivamente sul consenso esplicito degli Stati.
«[...] treaty means an international agreement concluded between States in written form and governed by
international law, whether embodied in a single instrument or in two or more related instruments and
whatever its particular designation».
VCLT, Art. 2(1)(a)
Possono avere tre funzioni rispetto alla consuetudine:
• Funzione dichiaratoria o ricognitiva;
• Funzione di cristallizzazione;
• Funzione di promozione o generativa.
North Sea Continental Shelf (Federal Republic of Germany v. Denmark/Federal
Republic of Germany v. The Netherlands), in ICJ Reports, 1969, pp. 42-47
• Basata sull’omogeneità di valori (jus pubblicum euroepeum).
• Principi generali costituenti di carattere consuetudinario
(consuetudo est servanda; pacta sunt servanda).
• Reciprocità.
• Prime norme sul trattamento dei cittadini, delle società e degli
organi stranieri, nonché in materia di diritto bellico.
• Diverse dagli «usi» e dalle «regole di cortesia» (cfr. contromisure e
Due elementi
Opinio iuris
sive necessitatis
Dichiarazione di accettazione unilaterale della giurisdizione della
Corte degli Stati Uniti:
«[The US will accept the jurisdiction of the Court for] disputes arising
under a multilateral treaty, unless (1) all parties to the treaty affected by the
decision are also parties to the case before the Court, or (2) the United
States of America specially agrees to jurisdiction».
Case Concerning Military and Paramilitary Activities in and Against Nicaragua, I.C.J. Reports, 1986, p. 31
«183. [...] the Court has next to consider what are the rules of customary international law applicable to the present dispute. For
this purpose, it has to direct its attention to the practice and opinio juris of States […]. In this respect the Court must not lose sight
of the Charter of the United Nations and that of the Organization of American States, notwithstanding the operation of the
multilateral treaty reservation. Although the Court has no jurisdiction to determine whether the conduct of the United States
constitutes a breach of those conventions, it can and must take them into account in ascertaining the content of the customary
international law which the United States is also alleged to have infringed.
184. The Court notes that there is in fact evidence, to be examined below, of a considerable degree of agreement between the
Parties as to the content of the customary international law relating to the non-use of force and non-intervention. This
concurrence of their view does not however dispense the Court from having itself to ascertain what rules of customary law are
applicable. The mere fact that States declare their recognition of certain rules is not sufficient for the Court to consider these as
being part of customary international law, and as applicable as such to those States. Bound as it is by Article 38 of its Statute to
apply, inter alia, international custom “as evidence of a general practice accepted as law”, the Court may not disregard the essential
role played by general practice. […]The Court must satisfy itself that the existence of the rule in the opinio juris of States is
confirmed by practice».
Ibidem, pp. 97
«186. It is not to be expected that in the practice of States the application of the rules in question should have been perfect, in the
sense that States should have refrained, with complete consistency, from the use of force or from intervention in each other’s
internal affairs. The Court does not consider that, for a rule to be established as customary, the corresponding practice must be in
absolutely rigorous conformity with the rule. In order to deduce the existence of customary rules, the Court deems it sufficient that
the conduct of States should, in general, be consistent with such rules, and that instances of State conduct inconsistent with a given
rule should generally have been treated as breaches of that rule, not as a recognition of a new rule. If a State acts prima facie
incompatible with a recognized rule, but defends its conduct by appealing to exceptions or justifications contained within the rule
itself, then whether or not the State’s conduct is in fact justifiable on that basis, the significance of that attitude is to confirm rather
than to weaken the rule».
Ibidem, pp. 98
«The reason that the prohibition on torture continues to be a requirement of
customary international law, even though widely abused, is not because it has a higher
normative status that allows us to ignore the abuse, but because opinio juris as to its
normative status continues to exist. No state, not even a state that tortures, believes
that the international law prohibition is undesirable and that it is not bound by the
prohibition. A new norm cannot emerge without both practice and opinio juris; and an
existing norm does not die without the great majority of states engaging in both a
contrary practice and withdrawing their opinio juris»
HIGGINS, Problems and Process: International Law and How to Use It, Clarendon Press, Oxford, 1994, p. 22
«188. [...] This opinio juris may, though with due caution, be deduced from, inter alia, the attitude of the Parties and the attitude of
States towards certain General Assembly resolutions, and particularly resolution 2625 (XXV) entitled “Declaration on Principles on
International Law concerning Friendly Relations and Co-operation among States in accordance with the Charter of the United
Nations”. The effect of consent to the text of such resolutions cannot be understood as merely that of a “reiteration or
elucidation” of the treaty commitment undertaken in the Charter. On the contrary, it may be understood as an acceptance of the
validity of the rule or set of rules declared by the resolution by themselves. [...]
189. As regards the United States in particular, the weight of an expression of opinio juris can similarly be attached to its support of
the resolution of the Sixth International Conference of American States condemning aggression (18 February 1928) and
ratification of the Montevideo Convention on the Rights and Duties of States (26 December 1933) [...]. Also significant is the
United States acceptance of the principle of the prohibition of the use of force which is contained in the declaration on principles
governing the mutual relations of States participating in the Conference on Security and Co-operation in Europe (Helsinki, 1
August 1975), whereby the participating States undertake to refrain in their mutual relations, as well as in their international relations in
general (emphasis added) from the threat or use of force. Acceptance of a text in these terms confirms the existence of an opinio
juris of the participating States prohibiting the use of force in international relations».
Case Concerning Military and Paramilitary Activities in and Against Nicaragua, I.C.J. Reports, 1986, pp. 99-100
«190. A further confirmation of the validity as customary international law of the principle of the prohibition of the use of force
expressed in Article 2, paragraph 4 of the Charter of the United Nations may be found in the fact that it is frequently referred to in
statements by State representatives as being not only a principle of customary international law but also a fundamental or cardinal
principle of such law. The International Law Commission, in the course of its work on the codification of the law of treaties,
expressed the view that the law of the Charter concerning the prohibition of the use of force in itself constitutes a conspicuous
example of a rule in international law having the character of jus cogens […]
191. As regards certain particular aspects of the principle in question, [...] the Court can again draw on the formulations contained
in the Declaration on Principles on International Law concerning Friendly Relations and Co-operation among States in accordance
with the Charter of the United Nations (General Assembly resolution 2625 (XXV) referred to above). As already observed, the
adoption by States of this text affords an indication of their opinio juris as to customary international law on the question.
Alongside certain descriptions which may refer to aggression, this text includes others which refer only to less grave forms of the
use of force. In particular, according to this resolution:
“[...] Every State has the duty to refrain from organizing or encouraging the organization of irregular forces or armed bands,
including mercenaries, for incursion into the territory of another State.
Every State has the duty to refrain from organizing, instigating, assisting or participating in acts of civil strife or terrorist acts in
another State or acquiescing in organized activities within its territory directed towards the commission of such acts, when the acts
referred to in the present paragraph involve a threat or use of force”».
Case Concerning Military and Paramilitary Activities in and Against Nicaragua, I.C.J. Reports, 1986, pp. 100-101
«193. The general rule prohibiting force allows for certain exceptions. [...] First, with regard to the existence of [the right of selfdefense], it notes that in the language of the United Nations Charter, the inherent right (or “droit naturel”) which any State
possesses in the event of an armed attack, covers both collective and individual self-defense. Thus, the Charter itself testifies to the
existence of the right of collective self-defense in customary international law. Moreover, just as the wording of certain General
Assembly declarations adopted by States demonstrates their recognition of the principle of the prohibition of force as definitely a
matter of customary international law, some of the wording in those declarations operates similarly in respect of the right of selfdefense (both collective and individual). Thus, in the declaration quoted above on the Principles on International Law concerning
Friendly Relations and Co-operation among States in accordance with the Charter of the United Nations, the reference to the
prohibition of force is followed by a paragraph stating that:
“nothing in the foregoing paragraphs shall be construed as enlarging or diminishing in any way the scope of the provisions of the
Charter concerning cases in which the use of force is lawful”.
This resolution demonstrates that the States represented in the General Assembly regard the exception to the prohibition of force
constituted by the right of individual or collective self-defence as already a matter of customary international law».
Case Concerning Military and Paramilitary Activities in and Against Nicaragua, I.C.J. Reports, 1986, pp. 102-103
• La Corte internazionale di giustizia ha sostenuto questa posizione anche successivamente
«General Assembly resolutions, even if they are not binding, may sometimes have normative value. They can, in
certain circumstances, provide evidence important for establishing the existence of a rule or the emergence of an
opinio juris. To establish whether this is true of a given General Assembly resolution, it is necessary to look at its
content and the conditions of its adoption; it is also necessary to see whether an opinio juris exists as to its
normative character. Or a series of resolutions may show the gradual evolution of the opinio juris required for the
establishment of a new rule».
Advisory Opinion on the Legality of the Threat or Use of Nuclear Weapons, in I.C.J. Reports, 1996, p. 826
• Posizione sostenuta anche da giudici nazionali: ad esempio, si pensi alla causa Filartiga c. Peña-Irala di fronte alla
United States Court of Appeals for the Second Circuit.
1. Fonte con ruolo integrativo.
«[I]l richiamo ai principi generali del diritto permette [...] di ricomprendere, nell’ambito
dell’elencazione contenuta nello Statuto della Corte, una categoria residuale di norme di
diritto internazionale generale».
GAJA, Principi del diritto (Diritto internazionale), in Enciclopedia del Diritto, vol. XXXV, 1986, p. 537
2. Difficilmente a fondamento esplicito di decisioni internazionali.
«Whilst it is difficult to find decisions of international tribunals expressly based upon
general principles, such principles often play a significant role as part of the legal
reasoning in decisions».
BROWNLIE, The Rule of Law in International. International Law at the Fiftieth Anniversary of the United
Nations, The Hague-London-Boston, 1998, p. 23
3. Largamente riconosciuti dalla giurisprudenza nazionale.
«Costituisce un principio di diritto internazionale consuetudinario
quello per cui uno Stato deve astenersi dall’esercitare i suoi poteri
sovrani quando ciò implichi ingerenza sugli organi di rilevanza
internazionale di un altro ente sovrano che operino nell’ambito del
territorio di tale Stato (nella specie, il principio viene enunziato in
riferimento agli enti centrali della Chiesa Cattolica)».
Marcinkus e altri, Cassazione Penale, sentenza, 17 luglio 1987, riprodotta in Rivista di
diritto internazionale, 1988, pp. 216 ss.
«Un principio generalmente riconosciuto nella comunità internazionale
– e di cui sono espressione l’art. 2 della Dichiarazione universale dei
diritti dell’uomo del 10 dicembre 1948 e l’art. 14 della Convenzione
europea per la salvaguardia dei diritti dell’uomo e delle libertà
fondamentali del 1950 – vieta di discriminare i soggetti in quanto tali
per ragioni, tra l’altro, di lingua».
Provincia autonoma di Triete c. Regione Friuli Venezia Giulia, Consiglio di Stato, sentenza,
3 ottobre 1990, riprodotta in Rivista di diritto internazionale privato e processuale, 1991,
pp. 792 ss.
«L’adeguamento automatico dell’ordinamento italiano alle norme di
diritto internazionale generalmente riconosciute, sancito dall’art. 10,
comma 1° Cost., si riferisce per giurisprudenza consolidata a principi
generali ovvero a norme di carattere consuetudinario. Un principio di
questo tipo o una consuetudine non è rinvenibile in tema di inflizione
della pena dell’ergastolo ad imputati minori, dal momento che dal
variegato panorama delle legislazioni degli altri Stati più affini a quella
del nostro Paese non risulta l’esistenza di norme internazionali
generalmente riconosciute, tenuto conto della estrema diversità delle
discipline che regolano il regime delle pene più gravi nei vari Paesi».
Corte Costituzione, sentenza n. 168, 28 agosto 1994, riprodotta in Rivista di diritto
internazionale, 1994, pp. 518 ss.
4. Ruolo fondamentale anche dal punto di vista procedurale o interpretativo.
5. Alcuni esempi:
• Buona fede
• Equità (secundum, infra e contra legem)
• Estoppel/Non contraddizione
• Legittimo affidamento
Possono essere fonti di obblighi internazionali.
«It is well recognized that declarations made by way of unilateral acts, concerning legal or factual
situations, may have the effect of creating legal obligations. […] An undertaking of this kind, if given
publicly, and with an intent to be bound, even though not made within the context of international
negotiation, is binding».
Nuclear Tests (Australia v. France), in ICJ Reports, 1974, par. 43, p. 267
Fonte diversa da quella pattizia.
«[i]n practice, it is often difficult to establish whether the legal effects stemming from the unilateral
behaviour of a State are the consequence of the intent that it has expressed or depend on the
expectations that its conduct has raised among other subjects of international law […]».
INTERNATIONAL LAW COMMISSION, Guiding Principles applicable to unilateral declarations of States capable of creating legal
obligations, Preambolo
Un esempio: la vertenza tra Italia e India sui due fucilieri del Battaglione San Marco (‘caso marò’).
Non vincolanti (non-legally binding).
Non dotati di una denominazione rigida: Carta (Charter), Dichiarazione (Declaration), Piano d’azione (Plan of
Action), Regole modello (Model Rules), Codice di condotta (Code of Conduct) o Linee-guida (Guidelines).
Possono svolgere funzione dichiarativa, cristallizzatrice o generativa di consuetudini internazionali.
Sono impegni politici, ma che risentono fortemente del principio di buona fede.
«When States enter into a non-legal commitment, they generally assume a political (or moral) obligation to
carry it out in good faith. Other States concerned have reason to expect such compliance and to rely on it.
What we must deduce from this is that the non-binding declarations that express political or moral
commitments are governed by the general principle of good faith. Inasmuch as good faith is an accepted
general principle of international law, it is appropriate to apply it to such commitments. There is no reason for
distinguishing the legal meaning of “good faith” from a supposed political meaning of that concept. Whether
called legal or political, its meaning is essentially the same. A significant legal consequence of the “good faith”
principle is that a party which committed itself in good faith to a course of conduct or to recognition of a
legal situation would be stopped from acting inconsistently with its commitment or position […]»
SCHACHTER, Non-Conventional Concerted Acts, in BEDJAOUI (ed.), International Law: Achievements and Prospects, Dordrecht, 1991,
pp. 265 ss., p. 267
5. I principali ambiti di applicazione sono:
Diritti umani (ad es: Dichiarazione universale dei diritti dell’uomo);
Diritto dell’economia (ad es: UNCTAD Code of Conduct on the Transfer of
Diritto dell’ambiente (ad es: Agenda 21, Dichiarazione di Rio del 1992,
Convenzioni quadro).
«[...] new norms and standards have been developed, set forth in a great number of
instruments over the last two decades. Such norms have to be taken into
consideration, and such new standards given proper weight, not only when States
contemplate new activities but also when continuing with activities begun in the past.
This need to reconcile economic development with protection of the environment is
aptly expressed in the concept of sustainable development»
Gabčíkovo-Nagymaros Project (Hungary v. Slovakia), in ICJ Reports, 1997, p. 78
6. Parte della dottrina sostiene che abbiano un “effetto di liceità”.
«Riteniamo che la raccomandazione produca, a termini della Carta, un effetto che può chiamarsi
di liceità. Riteniamo cioè che non commetta illecito lo Stato il quale, per eseguire una
raccomandazione di un organo dell’ONU, tenga un contegno contrario ad impegni
precedentemente assunti mediante accordo oppure ad obblighi derivanti da diritto internazionale
consuetudinario. L’effetto di liceità è da ammettere solo nel rapporto tra gli Stati membri, ed è
da ammettere, in applicazione di quanto abbiamo sempre sostenuto circa il dovere degli organi
di rispettare la Carta, solo in ordine alle raccomandazioni legittime. Entro questi limiti esso può
essere dedotto dall’obbligo di cooperazione che gli Stati membri hanno assunto nell’aderire alla
Carta e dal potere attribuito all’ONU di perseguire, sia pure mediante atti non vincolanti, fini
generali. In altri termini, la possibilità per gli organi dell’ONU di indicare agli Stati membri quali
contegni siano necessari nell’interesse comune non avrebbe senso se non comportasse la
rinuncia da parte del singolo Stato a denunciare l’eventuale illiceità, alla luce di norme diverse da
quelle statutarie, dei contegni raccomandati»
CONFORTI, FOCARELLI (a cura di), Le Nazioni Unite, Padova, 2010, p. 298
Principali vantaggi rispetto ad uno strumento convenzionale:
Negoziazione più agevole;
Maggiore flessibilità e agilità delle procedure di adozione e funzionamento;
Maggiore elasticità e flessibilità nella revisione;
Minore rischio di “smontare” il diritto consuetudinario.
8. Principali svantaggi rispetto ad uno strumento convenzionale:
Non ha natura vincolate;
Non gode dello stesso livello di pubblicità;
Presenta maggiori ostacoli durante l’applicazione procedurale e sul versante istituzionale
(coinvolgimento parlamentare, attuazione tramite amministrazioni dello Stato, etc etc).