State responsibility

1. The basic rule

Article 1 of ARSIWA: every internationally wrongful act of a State entails the international responsibility of that State. The PCIJ in Chorzów Factory (Germany v. Poland, jurisdiction 1927, merits 1928) called it a principle of international law that the breach of an engagement involves an obligation to make reparation in an adequate form.

Article 2: there is an internationally wrongful act when conduct consisting of an action or omission (a) is attributable to the State under international law and (b) constitutes a breach of an international obligation of the State. Two points follow:

• Omission counts. Failure to act when there is a duty to act (to warn, to prevent, to punish) is enough, as in Corfu Channel.
• Fault and damage are not separate general requirements. Whether fault (intent or negligence) is needed depends on the primary obligation breached. Many obligations of protection are obligations of due diligence, so the question becomes whether the State took reasonable care.

Article 3: whether an act is wrongful is governed by international law, and its lawfulness under internal law is irrelevant.

2. Theories: fault and risk

The subjective (fault) theory (Grotius, Oppenheim) requires intention or negligence by the State's agents. The objective (risk) theory (Anzilotti, Starke) holds the State responsible for an unlawful act of its organ whatever the fault, as in the Caire claim (France v. Mexico, 1929), where Mexico was liable for the murder of a Frenchman by Mexican officers acting under cover of their status. ARSIWA leaves the matter to the primary rule.

3. Attribution

• Organs of the State (Article 4): the conduct of any organ, legislative, executive, judicial or other, of central or local government, is the act of the State.
• Entities exercising governmental authority (Article 5), such as a private security company running a prison.
• Ultra vires acts (Article 7): conduct of an organ acting in that capacity is attributed even if it exceeds authority or contravenes instructions. Youmans claim (USA v. Mexico, General Claims Commission, 1926): Mexican troops sent to protect three Americans from a mob at Angangueo joined the mob and killed them. Mexico was liable: the soldiers were acting as a unit under an officer, and acts of soldiers in breach of orders are still acts of the State.
• Persons acting on the instructions, or under the direction or control, of the State (Article 8). Nicaragua (ICJ, 1986) required effective control of the particular operation; general support for the contras was not enough. Confirmed in Bosnian Genocide (ICJ, 2007).
• Insurrectional movements (Article 10): the conduct of a movement that becomes the new government is attributed to the State.
• Conduct acknowledged and adopted by the State as its own (Article 11). United States Diplomatic and Consular Staff in Tehran (USA v. Iran), ICJ, 1980: the militants who seized the embassy in 1979 were not State agents at first, but Iran was responsible for failing to protect the embassy, and, once Ayatollah Khomeini approved the occupation and decided to maintain it, the militants' acts became acts of the State.

Private persons and mobs. The acts of private persons are not attributable as such. The State is responsible only for its own failure: to take reasonable precautions to prevent the injury, or to apprehend, prosecute and punish the wrongdoers. In the Janes claim (USA v. Mexico, 1926), Mexico was liable for failing to take proper steps to arrest the murderer of an American. In the Home Missionary Society claim (USA v. Great Britain, 1920), Britain was not liable for injuries in a revolt in Sierra Leone, since it had shown no lack of good faith or negligence in suppressing it. A State is not an insurer of foreigners against every harm.

4. Circumstances precluding wrongfulness

Consent (Article 20); self-defence in conformity with the Charter (Article 21); countermeasures (Article 22); force majeure (Article 23); distress (Article 24); and necessity, which may be invoked only where the act is the only way to safeguard an essential interest against a grave and imminent peril and does not seriously impair an essential interest of the other State (Article 25). In Gabčíkovo-Nagymaros Project (Hungary/Slovakia), ICJ, 1997, Hungary's plea of ecological necessity failed. None of these justifies breach of a peremptory norm (Article 26).

5. Consequences: reparation

The responsible State must cease the act and offer assurances of non-repetition (Article 30), and make full reparation for the injury (Article 31). Chorzów Factory: reparation must, as far as possible, wipe out all the consequences of the illegal act and re-establish the situation which would in all probability have existed if that act had not been committed. Forms (Article 34):

• Restitution (Article 35), restoring the earlier situation, if not materially impossible or disproportionate;
• Compensation (Article 36) for financially assessable damage, including loss of profits;
• Satisfaction (Article 37): acknowledgment, expression of regret, formal apology. In Corfu Channel the Court's declaration that the British minesweeping violated Albanian sovereignty was itself appropriate satisfaction. The Rainbow Warrior affair (New Zealand v. France, 1986 and 1990) also involved apology and compensation.

6. Injury to aliens and diplomatic protection

When a State injures a foreign national, the national's State may take up the claim by diplomatic protection; it is then asserting its own right (Mavrommatis, PCIJ, 1924). Two conditions:

• Nationality of the claim: the injured person must be a national of the claimant State, by a genuine link (Nottebohm, ICJ, 1955). For companies, the State of incorporation, not the shareholders' State, has standing (Barcelona Traction, ICJ, 1970).
• Exhaustion of local remedies: the injured person must first use the remedies available in the courts of the respondent State (Interhandel, Switzerland v. USA, ICJ, 1959; ARSIWA Article 44).

On the standard of treatment, Western States argued for an international minimum standard; Latin-American States (the Calvo doctrine) argued for national treatment. The Neer claim (USA v. Mexico, 1926) fixed a high threshold: treatment amounting to outrage, bad faith, wilful neglect of duty, or insufficiency of governmental action so far short of international standards that every reasonable person would recognise it.

7. Transboundary harm

Trail Smelter (USA v. Canada, arbitral awards of 1938 and 1941). A smelter at Trail, British Columbia, emitted sulphur dioxide that damaged crops and forests in the State of Washington. The tribunal held that no State has the right to use or permit the use of its territory in such a manner as to cause injury by fumes in or to the territory of another or the property or persons therein, when the case is of serious consequence and the injury is established by clear and convincing evidence. Canada was ordered to pay compensation and the smelter was required to operate under a control regime. This is sic utere tuo ut alienum non laedas in international law, later stated in Principle 21 of the Stockholm Declaration (1972), Principle 2 of the Rio Declaration (1992), and Pulp Mills (Argentina v. Uruguay), ICJ, 2010, which added a duty to carry out an environmental impact assessment.

8. Problem: poisonous gas across the border

A factory in State X releases poisonous gas, which the wind carries into neighbouring State Y, causing heavy loss. Can X be held responsible? (February 2025)

Issue. Whether a State is internationally responsible for transboundary harm caused by a private factory on its territory.

Law. A State must not use or permit the use of its territory to cause serious injury to another State (Trail Smelter; Corfu Channel). The obligation is one of due diligence: to regulate, monitor and prevent significant harm, and to provide for compensation. A State is responsible for its own omission in failing to prevent or control the harm (ARSIWA, Articles 2 and 31).

Application. The factory is private, so its emission is not itself an act of X. But it is within X's territory and control; X licensed and regulated it, or ought to have. The harm is serious and, on the facts, established. The case is on the facts of Trail Smelter, where Canada was liable for a private smelter's fumes. X's responsibility is engaged unless it can show it exercised due diligence and the release was wholly unforeseeable (force majeure). Y must also show causation by clear and convincing evidence.

Conclusion. X is responsible and must pay compensation, take measures to prevent repetition, and may be required to control or close the source. Individuals harmed in Y may also sue the factory in X's courts. The Bhopal gas leak (1984) is an Indian illustration of the private-law side.

9. Problem: a foreigner injured by a mob

A national of State A, while travelling in State B, was attacked during mob rioting. Can B be held responsible? (August 2024)

Issue. Whether a State is responsible for injury to an alien caused by private rioters.

Law. Acts of private persons are not attributable to the State. The State is responsible only for its own lack of due diligence in preventing the attack or punishing the offenders (Janes; Home Missionary Society), or where its own officials participated (Youmans; ARSIWA Article 7). Local remedies must be exhausted first.

Application. If B's police were present and did nothing, or the riot was foreseeable and no precautions were taken, or B failed to investigate and prosecute afterwards, B has failed in due diligence and is responsible. If police joined the mob, B is directly responsible as in Youmans. If B acted promptly and in good faith to suppress a sudden riot and has prosecuted the offenders, B is not responsible, since it is not an insurer.

Conclusion. B is not automatically responsible. Responsibility depends on proof of lack of due diligence or participation by its agents; A may present a claim by diplomatic protection after its national has exhausted remedies in B.

How this is examined

Answer every problem in the four steps above, naming ARSIWA Article 2 and the case on which the facts are modelled. As a short note on Youmans: facts, the holding on ultra vires acts of soldiers, and Article 7 of ARSIWA.