Diplomatic protection is the process by which a State invokes the international responsibility of another State for an internationally wrongful act causing injury to one of its nationals. It provides a mechanism through which an individualβs injury may become the subject of an international claim by the State of nationality.
- Meaning of Diplomatic Protection
- Legal Nature of Diplomatic Protection
- Diplomatic Protection and State Responsibility
- Nationality of the Injured Person
- Continuous Nationality
- Nationality Acquired After the Injury
- Dual Nationality
- MergΓ© Claim
- Diplomatic Protection of Corporations
- Barcelona Traction Case
- Protection of Shareholders
- Local Remedies Rule
- Purpose of Exhaustion of Local Remedies
- Exceptions to the Local Remedies Rule
- Discretionary Nature
- Diplomatic Protection and Consular Assistance
- Diplomatic Protection and Diplomatic Immunity
- Diplomatic Protection and Human Rights
- Forms of Diplomatic Protection
- Reparation
- Diplomatic Protection and Use of Force
- International Law Commission Draft Articles
- Article 1
- Article 2
- Article 3
- Nottebohm Case
- Ahmadou Sadio Diallo Case
- Refugees and Stateless Persons
- Diplomatic Protection and International Organisations
- Common Confusions
- Topic at a Glance
- Quick Revision
- Conclusion
Meaning of Diplomatic Protection
Diplomatic protection arises when a State takes up the claim of its national against another State for an internationally wrongful act.
The basic process is:
National of State A
β
Suffers injury caused by State B
β
State A invokes the responsibility of State B
Diplomatic protection may be exercised through:
- diplomatic negotiations;
- diplomatic protests;
- international claims;
- arbitration;
- proceedings before an international court.
Legal Nature of Diplomatic Protection
Diplomatic protection is fundamentally a right of the State, rather than an individual right under general International Law.
Although the individual suffers the injury, the international claim is presented by the State of nationality.
Therefore:
Individual injury β State of nationality β International claim
The State generally has discretion to decide whether to exercise diplomatic protection.
Diplomatic Protection and State Responsibility
Diplomatic protection is closely connected with the law of State responsibility.
For diplomatic protection to arise, there must generally be:
- an internationally wrongful act;
- injury to a national of the protecting State;
- the required nationality connection;
- satisfaction of applicable procedural requirements.
If the requirements are satisfied, the protecting State may invoke the responsibility of the offending State.
Nationality of the Injured Person
Nationality is the central connecting factor in diplomatic protection.
For example:
Person X β national of State A
Internationally wrongful act β committed by State B
State A β may potentially exercise diplomatic protection
The State exercising protection must therefore generally be the State of nationality of the injured person.
Continuous Nationality
The traditional continuous nationality rule requires the injured person to maintain the relevant nationality during the legally significant stages of the claim.
The nationality requirement generally concerns both:
- the time when the injury occurred; and
- the time when the claim is presented.
The precise application depends upon the circumstances and applicable International Law.
Nationality Acquired After the Injury
A State cannot ordinarily create a diplomatic protection claim simply by granting its nationality to a person after the injury has occurred.
Nationality must generally exist at the relevant time under the applicable rules.
Dual Nationality
Diplomatic protection can become complicated where a person possesses the nationality of more than one State.
Questions may arise concerning:
- which State can exercise protection;
- whether the claim is against a State of which the person is also a national;
- which nationality is considered effective or dominant.
The applicable rules depend upon the circumstances.
MergΓ© Claim
The MergΓ© Claim (1955) is associated with the principle of effective or genuine nationality in cases involving dual nationality.
It is commonly discussed in connection with determining which nationality should prevail for purposes of diplomatic protection.
Diplomatic Protection of Corporations
Diplomatic protection may also concern legal persons, particularly companies.
Corporate nationality can create difficult questions because a company may have connections with several States.
For example:
Incorporated in State A
Shareholders from State B
Operations in State C
Injury caused by State D
The relevant State for diplomatic protection depends upon the applicable rules concerning the nationality of the corporation and the nature of the injury.
Barcelona Traction Case
The leading case is:
Barcelona Traction, Light and Power Company, Limited (Belgium v. Spain), 1970
The company was incorporated in Canada, although many of its shareholders were Belgian nationals.
Belgium attempted to exercise diplomatic protection concerning alleged injury to the company caused by Spain.
The ICJ held that Canada, as the State of the companyβs nationality, was the appropriate State to exercise diplomatic protection concerning injury to the company itself.
Protection of Shareholders
The Barcelona Traction case established an important distinction between:
injury to a company
and
direct injury to shareholders.
The nationality of shareholders does not ordinarily give their State a right to exercise diplomatic protection for an injury suffered by the corporation itself.
However, shareholders may have separate rights where they themselves suffer a direct injury or where applicable rules provide otherwise.
Local Remedies Rule
A major requirement of diplomatic protection is the exhaustion of local remedies.
Generally, the injured person must first use the available and effective legal remedies in the State responsible for the alleged wrongful act.
The basic process is:
Internationally wrongful act
β
Domestic remedies
β
Exhaustion of available and effective remedies
β
Diplomatic protection
Purpose of Exhaustion of Local Remedies
The rule gives the responsible State an opportunity to:
- investigate the claim;
- correct the wrongful act;
- provide compensation;
- provide another appropriate remedy.
It also respects the domestic jurisdiction of the State concerned.
Exceptions to the Local Remedies Rule
The requirement is not absolute.
Exceptions may arise where:
- no adequate local remedy is available;
- available remedies are ineffective;
- proceedings are unduly prolonged;
- circumstances make exhaustion impossible;
- other recognised exceptions under International Law apply.
Discretionary Nature
A State generally has discretion whether to exercise diplomatic protection.
An individual does not ordinarily possess a general right under International Law to compel the State of nationality to take up the claim.
The State may consider:
- seriousness of the injury;
- diplomatic relations;
- available remedies;
- international interests;
- evidence;
- political and legal considerations.
Diplomatic Protection and Consular Assistance
Diplomatic protection must be distinguished from consular assistance.
Consular assistance may include:
- visiting nationals detained abroad;
- helping them communicate with family;
- providing information concerning local lawyers;
- issuing emergency travel documents;
- providing general assistance.
Diplomatic protection is different because it involves the international responsibility of another State.
Diplomatic Protection and Diplomatic Immunity
These two concepts are entirely different.
Diplomatic protection:
State A invokes the responsibility of State B for injury caused to a national of State A.
Diplomatic immunity:
A diplomatic agent is protected from certain jurisdictional and enforcement measures of the receiving State.
Therefore:
Diplomatic Protection β Diplomatic Immunity
Diplomatic Protection and Human Rights
Diplomatic protection also differs from international human rights procedures.
Under diplomatic protection:
State β presents claim on behalf of national
Under an applicable human rights mechanism:
Individual β may directly bring a claim before an international or regional body
The exact availability of direct individual petitions depends upon the relevant treaty and jurisdiction.
Forms of Diplomatic Protection
A State may exercise diplomatic protection through:
- diplomatic negotiations;
- formal protests;
- requests for cessation;
- claims for compensation;
- arbitration;
- international judicial proceedings;
- other peaceful dispute-settlement mechanisms.
Reparation
Where the responsible State is found internationally responsible, appropriate reparation may be required.
Forms of reparation may include:
Restitution
Restoring the situation that existed before the wrongful act, where possible.
Compensation
Payment for financially assessable injury.
Satisfaction
Measures addressing non-material injury, such as acknowledgment of the violation or an expression of regret, where appropriate.
Diplomatic Protection and Use of Force
Diplomatic protection does not give a State a general right to use force against another State.
Disputes must be addressed through peaceful means, consistently with the UN Charter and applicable International Law.
International Law Commission Draft Articles
The International Law Commissionβs Draft Articles on Diplomatic Protection, 2006 provide an important framework for the modern law of diplomatic protection.
They address:
- diplomatic protection;
- nationality;
- continuous nationality;
- local remedies;
- corporations;
- dual nationality;
- refugees;
- stateless persons.
Article 1
Article 1 defines diplomatic protection as the invocation by a State, through diplomatic action or other peaceful means, of the responsibility of another State for an injury caused by an internationally wrongful act to a natural or legal person who is a national of the former State.
Article 2
Article 2 recognises that a State has the right to exercise diplomatic protection.
It does not generally impose an automatic obligation on the State to exercise it.
Article 3
Article 3 deals with the State entitled to exercise diplomatic protection in relation to:
- natural persons;
- legal persons.
Nationality remains central to the exercise of protection.
Nottebohm Case
In Nottebohm (Liechtenstein v. Guatemala), 1955, the ICJ considered the nationality relied upon for diplomatic protection.
The case is particularly associated with the idea of a genuine connection between an individual and the State whose nationality is invoked.
The case remains an important authority in discussions concerning nationality and diplomatic protection.
Ahmadou Sadio Diallo Case
In Ahmadou Sadio Diallo (Republic of Guinea v. Democratic Republic of the Congo), 2010, the ICJ dealt with diplomatic protection in relation to an individual and considered issues concerning individual rights and corporate interests.
The case is important for understanding the modern application of diplomatic protection to individuals.
Refugees and Stateless Persons
Diplomatic protection traditionally depends upon nationality.
A stateless person therefore faces difficulties in obtaining diplomatic protection under the traditional nationality-based framework.
The ILC Draft Articles contain specific provisions concerning refugees and stateless persons.
Diplomatic Protection and International Organisations
Diplomatic protection is primarily a mechanism available to States.
It should therefore be distinguished from claims that international organisations may bring to protect their own rights and interests under their constituent instruments and International Law.

Common Confusions
Is diplomatic protection an individualβs right?
Generally, no. It is a right of the State under general International Law.
Must a State exercise diplomatic protection?
Generally, no. The State normally has discretion.
Must local remedies be exhausted?
Generally yes, subject to recognised exceptions.
Can diplomatic protection be exercised immediately after an injury?
Usually the local remedies rule must first be considered.
Can shareholders automatically claim diplomatic protection for a companyβs injury?
Generally no. Barcelona Traction is the leading authority.
Can a State use force to protect its nationals?
Diplomatic protection does not provide a general right to use force.
Is diplomatic protection the same as consular assistance?
No. Consular assistance is broader day-to-day assistance to nationals abroad, while diplomatic protection concerns an international claim involving State responsibility.
Is diplomatic protection the same as diplomatic immunity?
No.
What is the leading case?
Barcelona Traction (1970) is a leading case concerning corporate nationality and diplomatic protection.
Topic at a Glance
Point Position Meaning State invokes responsibility for injury to its national Nature State-to-State claim Main basis Nationality Protecting State State of nationality Requirement Internationally wrongful act and injury Local remedies Generally must be exhausted Stateβs decision Generally discretionary Natural persons Protection possible Corporations Corporate nationality is important Shareholders Nationality alone generally insufficient for corporate injury Remedies Restitution, compensation, satisfaction Leading case Barcelona Traction, 1970 Other cases Nottebohm, Diallo, MergΓ© Main framework ILC Draft Articles, 2006
Quick Revision
- Diplomatic protection allows a State to invoke the international responsibility of another State for injury to its national.
- It is fundamentally a State-to-State claim.
- The injured person must generally be a national of the protecting State.
- The State generally has discretion whether to exercise protection.
- The continuous nationality rule is important.
- The local remedies rule generally requires available and effective domestic remedies to be exhausted.
- Important exceptions may apply where local remedies are unavailable or ineffective.
- Barcelona Traction (1970) β corporate nationality and protection of companies.
- Nottebohm (1955) β nationality and genuine connection.
- Diallo (2010) β diplomatic protection and individual rights.
- MergΓ© Claim (1955) β dual nationality and effective nationality.
- Diplomatic protection is different from:
- diplomatic immunity;
- consular assistance;
- direct human rights petitions.
- Diplomatic protection does not authorise the use of force.
- The ILC Draft Articles on Diplomatic Protection, 2006 provide an important framework.
- The essential principle is:
Diplomatic protection enables a State to invoke the international responsibility of another State for an internationally wrongful injury suffered by its national, subject to the applicable rules concerning nationality and exhaustion of local remedies.
Conclusion
Diplomatic protection is an important mechanism of State responsibility through which a State may take up the international claim of its national against another State. The doctrine is based principally upon nationality, and the protecting State generally has discretion whether to exercise the right. The injured person will ordinarily be required to exhaust available and effective local remedies before an international claim is pursued, subject to recognised exceptions. The doctrine also contains important rules concerning continuous nationality, dual nationality, corporations and shareholders. Nottebohm, Barcelona Traction, MergΓ© and Ahmadou Sadio Diallo are important authorities in understanding these principles. Diplomatic protection must be distinguished from diplomatic immunity and consular assistance because it concerns the invocation of international responsibility, rather than the protection of diplomatic agents from foreign jurisdiction. The ILCβs Draft Articles on Diplomatic Protection, 2006 provide an important modern framework. Ultimately, diplomatic protection provides a peaceful legal mechanism through which a State can seek appropriate reparation where another State has committed an internationally wrongful act causing injury to its national.
