“Attribution” denotes “the operation of attaching a given action or omission to a State” under international law.¹ Under Article 2 of the Articles on State Responsibility, which is recognised as codifying existing international law,² attribution is one of the elements of an internationally wrongful act.³

The ILC Articles concern the responsibility of States for their internationally wrongful acts. They are not necessarily applicable to the issue of attribution of conduct to the State or State entities under municipal law or in respect of contractual liability, nor can they create or modify the extent or content of obligations arising under a contract.⁴ 

The procedural nature of the question on attribution has been discussed in-depth by tribunals.⁵ Some found it useful to sometimes deal with the matter on the jurisdictional stage.⁶ Others found it more convenient to analyze it on the merits.⁷

The rules of attribution under international law are reflected in the International Law Commission’s Articles on State Responsibility (“ILC Articles”). The relevant provisions of the ILC Articles have been recognised as reflecting customary international law.⁸ They apply to questions of international responsibility, including for the breach of obligations under bilateral or multilateral investment treaties, in investment arbitration,⁹ to the extent that an IIA or another special law does not displace them.¹⁰

Under international law, conduct (acts or omissions)¹¹ is attributed to a State in different ways, which are set out in Articles 4 through 11 of the ILC Articles. These rules are alternative routes to determine attribution and are mutually exclusive, since attribution can only be found under one article at a time.¹²

Under Article 4, the conduct of “any state organ,” whether it exercises “legislative, executive, and judicial or any other type of functions” is attributable to a State.¹³

“State organ” is understood in a broad sense, including organs of government and officials at all levels, whether at the central or local level.¹⁴ An entity can be defined as a de jure or de facto State organ.¹⁵

Numerous tribunals have found attribution of legislative acts to the State as emanating from its legislative power.¹⁶

In relation to the executive branch, tribunals have attributed to the State conduct of the Government, including its Ministers and other Government officials acting in such capacity.¹⁷ 

Public sector entities have also been considered as State organs,¹⁸ although certain tribunals have found that a public entity, having separate legal personality, may not be a “State organ” in the sense of Article 4 of the Articles on State Responsibility; however this does not necessarily imply that conduct of such entities is not attributable to the State under other rules and principles of attribution.¹⁹

Acts of the judiciary, including courts,²⁰ prosecutors,²¹ or enforcement agents²² are also considered as State acts.

The distinction between commercial acts or acta jure gestionis, on the one hand, and acta jure imperii, on the other hand, is not relevant for purposes of Article 4. The only requirement is that the act is performed by a State organ. All acts or omissions performed by a State organ are attributable to the State. Whether such conduct constitutes a breach of an international obligation, or a breach of contract is a separate and distinct question.

Article 5 concerns entities that are not State organs under Article 4, but are entities or State instrumentalities that are “empowered by the law of the State to exercise elements of governmental authority.”²³

The term “entity” under Article 5 covers a wide range of bodies or instrumentalities.²⁴ That may include public corporations, semi-public entities, public agencies, or certain private companies, among others.²⁵

Attribution under Article 5 requires two cumulative conditions: (1) an entity must be empowered with governmental authority and (2) there must be an act performed through the exercise of governmental authority.²⁶ 

Tribunals have often assessed attribution of conduct of State enterprises²⁷ or State agencies.²⁸ 

Tribunals often look at whether internal law delegates public authority to a specific entity or person,²⁹ although express delegation is not required.³⁰

Tribunals have often applied the distinction between acta jure gestionis and acta jure imperii to determine whether an entity or a person exercises governmental authority.³¹ Private or commercial activity is excluded from the application of this Article.³²

Even though conduct of private persons or entities is generally not attributable to the State,³³ a State may, through specific directions or by exercising control over a group, “in effect assume responsibility for their conduct.”³⁴

Article 8 covers two scenarios:³⁴ (i) where the person or entity “is in fact acting on the instructions” of the State;³⁵ or (ii) where it is acting “under the direction or control of the State.”³⁶

Tribunals often analyze control under the “effective control” test,³⁷ although others have applied a more flexible test.³⁸ The degree of control has been found to be relevant.³⁹

Unlike the previous ILC Articles, under Article 11 attribution does not arise at the time of the alleged wrongful act, but only subsequently if acknowledged and adopted by the State.⁴⁰ It concerns mainly acts and omissions committed by private persons and entities.⁴¹

Commentary suggests that the State must adopt the conduct “as its own,” and therefore mere support or endorsement is not enough.⁴² Acknowledgement and adoption of the conduct can occur through State organs, but also through its instrumentalities.⁴³

Even if a State acknowledges and adopts a conduct as its own, it must still be found to be wrongful in accordance with the State’s international obligations.⁴⁴

The ILC Articles also regulate other forms of attribution that have appeared less frequently in practice and are referred to as “special” cases by the ILC Commentary.

Article 6 “deals with the limited and precise situation in which an organ of a State is effectively put at the disposal of another State so that the organ may temporarily act for its benefit and under its authority.”⁴⁵ If the organ on State acts exclusively on behalf of another State, the act will be attributed to that latter State.⁴⁶

Article 7 deals with excess of authority or contravention of instructions,⁴⁷ and provides that even in those circumstances, the conduct of a State organ or a person or entity that is empowered to exercise governmental authority will be attributed to the State, as long as it acts in that capacity.⁴⁸

Article 9 provides that the conduct of a person exercising elements of governmental authority in the absence or default of the official authorities may also be considered an act of a State under international law.⁴⁹ As the commentary explains, it is an exceptional case which will rarely occur, in circumstances such as a revolution, armed conflict or foreign occupation.⁵⁰

Lastly, Article 10 deals with conduct of an insurrectional or other movement, including in circumstances where such movement succeeds in establishing a new State.⁵¹