Treatment of Aliens

Treatment of Aliens in International Law concerns the legal status, rights, protections and obligations of persons who are nationals of one State but are present or residing within the territory of another State. International Law recognises the territorial sovereignty of States while also requiring them to observe certain international standards in their treatment of foreign nationals.

Meaning of an Alien

An alien is a person who is not a national of the State in whose territory the person is present.

For example:

National of State A

↓

Present in State B

↓

Person is an alien in State B

An alien may be:

• a tourist;
• student;
• worker;
• businessperson;
• resident;
• refugee;
• temporary visitor.

The legal treatment may differ depending upon the person’s status and the applicable domestic and international law.

Legal Status of Aliens

International Law generally recognises that a State has sovereignty over persons within its territory.

Therefore, aliens are ordinarily subject to the laws and jurisdiction of the territorial State.

At the same time, the territorial State must respect applicable international obligations concerning:

• life and physical security;
• freedom from arbitrary detention;
• access to justice;
• property;
• fair treatment;
• human rights;
• diplomatic and consular relations.

Territorial Sovereignty

The treatment of aliens is closely connected with the principle of territorial sovereignty.

A State generally has the authority to determine:

• who may enter its territory;
• who may remain;
• conditions of residence;
• employment restrictions;
• immigration requirements;
• grounds for removal or expulsion.

However, these powers must be exercised consistently with International Law.

Admission of Aliens

International Law generally recognises the State’s authority to regulate the admission of foreigners.

A State may establish:

• visa requirements;
• immigration controls;
• residence permits;
• work permits;
• border controls.

There is generally no unrestricted international right of an alien to enter any foreign State.

Right of Entry

The general principle is:

A State has substantial discretion to determine which aliens may enter its territory.

However, treaty obligations, refugee law, human rights law and other international obligations may impose restrictions on this discretion.

Residence of Aliens

Once admitted, an alien may reside in the State subject to its immigration laws.

The State may establish different categories of residence, such as:

• temporary residence;
• permanent residence;
• student residence;
• employment-based residence.

Treatment According to International Law

The territorial State must treat aliens in accordance with applicable international obligations.

The traditional law of aliens developed around the principle that a State must provide a minimum international standard of treatment.

International Minimum Standard

The international minimum standard requires States to provide foreign nationals with certain basic protections recognised by International Law.

It may include protection against:

• denial of justice;
• arbitrary treatment;
• unlawful detention;
• serious violations of physical security;
• discriminatory or abusive State conduct.

The standard is not necessarily identical to the complete set of rights granted to nationals under domestic law.

National Treatment

Under national treatment, aliens receive treatment comparable to that provided to nationals of the territorial State.

For example:

Nationals → certain civil rights

↓

Aliens → same treatment where national-treatment rule applies

National treatment may arise from:

• domestic law;
• bilateral treaties;
• investment treaties;
• other international agreements.

Most-Favoured-Nation Treatment

Under a most-favoured-nation (MFN) clause, aliens of one State may receive treatment no less favourable than that provided to nationals of another specified foreign State.

MFN treatment depends upon the applicable treaty.

Minimum Standard vs National Treatment

These concepts should be distinguished. Minimum International Standard National Treatment Based on international standards Based on treatment of nationals Provides a minimum level of protection Requires comparable treatment Can exist even where aliens receive different treatment Depends upon treatment of nationals Important in State responsibility Often treaty-based

Human Rights of Aliens

Modern International Law recognises that many fundamental human rights apply to all persons, regardless of nationality.

Aliens may therefore enjoy rights concerning:

• life;
• physical integrity;
• liberty;
• fair trial;
• freedom from torture;
• freedom of religion;
• protection of property;
• access to courts.

The precise scope depends upon the relevant international instruments and the person’s legal status.

Equality and Non-Discrimination

States must comply with applicable international rules prohibiting discrimination.

However, International Law does not necessarily require complete equality between nationals and aliens in every area.

States may legitimately reserve certain rights for their own nationals, particularly:

• voting;
• holding certain public offices;
• certain political rights.

Civil Rights

Aliens may generally enjoy civil rights subject to domestic law and applicable treaties.

These may include rights relating to:

• contracts;
• property;
• employment;
• access to courts;
• personal security.

The scope varies according to the State and applicable international obligations.

Political Rights

States may reserve certain political rights for their nationals.

Aliens generally do not automatically have a right to:

• vote in national elections;
• stand for national political office;
• participate in certain sovereign governmental functions.

This distinction is generally accepted in International Law.

Right to Access Courts

An important protection is access to justice.

Aliens should generally be able to seek remedies through the legal system of the territorial State, subject to applicable law.

A serious denial of justice may engage the international responsibility of the State.

Denial of Justice

Denial of justice traditionally refers to serious failures in the administration of justice that violate applicable international standards.

Examples may include:

• refusal to provide judicial access;
• extreme judicial delay;
• fundamentally unfair proceedings;
• serious procedural irregularities;
• arbitrary judicial conduct.

A mere disagreement with a domestic court’s decision does not automatically constitute denial of justice.

Protection of Property

Aliens may possess property in a foreign State subject to its domestic law.

International Law may protect foreign-owned property against:

• arbitrary confiscation;
• unlawful expropriation;
• discriminatory treatment;
• failure to provide appropriate compensation where required.

The exact standard depends upon the applicable treaty and customary rules.

Expropriation

Where a State expropriates property belonging to an alien, questions may arise concerning:

• legality of the expropriation;
• public purpose;
• non-discrimination;
• due process;
• compensation.

Investment treaties may establish more detailed standards.

Criminal Jurisdiction

Aliens are generally subject to the criminal jurisdiction of the territorial State.

For example:

Foreign national commits offence in State B

↓

State B → may exercise territorial jurisdiction

Nationality does not ordinarily provide immunity from local criminal law.

Civil Jurisdiction

Aliens are also generally subject to the civil jurisdiction of the territorial State.

However, specific immunities may apply to:

• diplomats;
• consular officers;
• States;
• international organisations.

Arrest and Detention

Aliens may be arrested or detained in accordance with the domestic law of the territorial State.

However, detention must comply with applicable international standards, including protections against:

• arbitrary detention;
• torture;
• cruel or degrading treatment;
• denial of due process.

Consular Notification

Where an alien is arrested or detained, the Vienna Convention on Consular Relations, 1963 may require the receiving State to inform the person of relevant consular rights and facilitate communication with the person’s consular authorities.

This principle was examined by the ICJ in:

• LaGrand (2001);
• Avena (2004);
• Jadhav (2019).

Diplomatic Protection of Aliens

If an alien suffers an internationally wrongful injury, the person’s State of nationality may potentially exercise diplomatic protection.

For example:

National of State A

↓

Injured by State B

↓

State A → may invoke responsibility of State B

Diplomatic protection remains subject to applicable requirements, including nationality and exhaustion of local remedies.

Exhaustion of Local Remedies

Before diplomatic protection is generally exercised, the injured alien must ordinarily exhaust available and effective local remedies in the State responsible for the alleged wrongful act.

This gives the territorial State an opportunity to remedy the injury through its own legal system.

Expulsion of Aliens

A State generally possesses the sovereign power to expel aliens from its territory.

However, expulsion must comply with applicable International Law.

An alien should not be expelled:

• arbitrarily;
• without required procedural safeguards;
• to a State where international law prohibits removal;
• in violation of applicable refugee or human rights obligations.

Due Process in Expulsion

Depending upon the applicable legal framework, an alien facing expulsion may be entitled to:

• notice;
• an opportunity to present objections;
• review of the expulsion decision;
• other procedural safeguards.

The precise requirements depend upon the person’s status and the applicable treaty.

Non-Refoulement

The principle of non-refoulement prohibits States, in circumstances covered by international refugee and human rights law, from sending a person to a State where they face a prohibited risk, such as persecution or certain forms of serious harm.

This is particularly important for:

• refugees;
• asylum seekers;
• persons at risk of torture or serious human rights violations.

Refugees and Aliens

Refugees are a special category of aliens.

Although they are foreign nationals in the territorial State, they receive additional protection under international refugee law.

The 1951 Refugee Convention establishes important protections concerning:

• non-refoulement;
• legal status;
• employment;
• access to courts;
• documentation.

Treatment of Enemy Aliens

During armed conflict, the treatment of nationals of an enemy State may be subject to special rules under:

• International Humanitarian Law;
• the Geneva Conventions;
• applicable customary International Law.

However, enemy status does not remove all international protections.

Diplomatic and Consular Officials

Diplomatic agents and consular officers are technically foreign nationals in the receiving State but possess special privileges and immunities.

Therefore:

Ordinary alien → subject to local jurisdiction

Diplomat/consular officer → special international immunities

State Responsibility for Treatment of Aliens

A State may incur international responsibility if its treatment of an alien violates an applicable international obligation.

The wrongful conduct may involve:

• unlawful detention;
• denial of justice;
• unlawful expropriation;
• discrimination;
• physical mistreatment;
• failure to provide required judicial remedies.

Traditional Doctrine

Traditional International Law often focused on the international minimum standard as the benchmark for treatment of aliens.

The territorial State was expected to provide a minimum level of protection regardless of whether its treatment of its own nationals was lower.

Calvo Doctrine

The Calvo Doctrine, associated with Argentine jurist Carlos Calvo, argued that aliens should generally receive the same treatment as nationals and should rely upon local remedies rather than seeking special international protection through their home States.

The doctrine was particularly influential in Latin American international legal thought.

Calvo Clause

A Calvo Clause is a contractual provision under which a foreign investor agrees to submit disputes to the local courts and accepts treatment under local law.

Its historical development reflects the tension between:

• territorial sovereignty;
• protection of foreign nationals;
• diplomatic intervention.

Minimum Standard vs Calvo Doctrine

International Minimum Standard Calvo Doctrine Requires minimum international protection Emphasises national treatment/local remedies Alien may receive international protection Alien should generally rely on local legal system Important in State responsibility Emphasises territorial sovereignty Developed strongly in traditional international claims Strongly associated with Latin American practice

Barcelona Traction and Aliens

The treatment of aliens also intersects with diplomatic protection and corporate nationality.

In Barcelona Traction (Belgium v. Spain), 1970, the ICJ distinguished between the nationality of a company and the nationality of its shareholders.

The case is particularly important when determining which State may exercise diplomatic protection.

Common Confusions

Can a State refuse entry to aliens?

Generally, States have broad authority to regulate entry, subject to applicable international obligations.

Do aliens have the same rights as nationals?

Not necessarily. Fundamental human rights generally apply to all persons, but certain political rights may be reserved for nationals.

Are aliens subject to local criminal law?

Yes, generally.

Can an alien be expelled?

Generally yes, subject to International Law and applicable procedural, refugee and human rights protections.

Can an alien own property?

This depends upon domestic law and applicable treaties.

What is the international minimum standard?

The minimum level of treatment required by International Law for foreign nationals.

What is denial of justice?

A serious failure in the administration of justice that violates applicable international standards.

What is non-refoulement?

A principle prohibiting removal in circumstances where international law protects a person from being sent to a place where they face a prohibited risk.

What is the Calvo Doctrine?

A doctrine emphasising local remedies and national treatment for aliens rather than special international protection.

Topic at a Glance

Point Position Alien Non-national present in a State Main principle Territorial sovereignty Entry Generally regulated by territorial State Local law Generally applies to aliens Minimum standard International protection threshold National treatment Treatment comparable to nationals where applicable Political rights May be reserved for nationals Civil rights Protected subject to applicable law Access to courts Generally available Criminal jurisdiction Generally territorial Property Protected under applicable law Expulsion Permitted subject to International Law Non-refoulement Important refugee/human-rights protection Consular protection Available through State of nationality Diplomatic protection May be exercised by State of nationality Key doctrine International minimum standard Historical doctrine Calvo Doctrine

Quick Revision

• An alien is a person who is not a national of the State in whose territory they are present.
• Aliens are generally subject to the territorial jurisdiction of the State.
• States have broad authority to regulate:
  • admission;
  • residence;
  • employment;
  • expulsion.
• International Law nevertheless requires an applicable minimum standard of treatment.
• Aliens generally enjoy fundamental human rights.
• Certain political rights may be reserved for nationals.
• Aliens are generally entitled to access courts and protection against serious denial of justice.
• Foreign property may receive international protection against unlawful or discriminatory expropriation.
• Aliens may be arrested and prosecuted under local law, subject to international standards.
• Consular notification is important when foreign nationals are arrested or detained.
• Expulsion must comply with applicable International Law.
• Non-refoulement limits removal in cases covered by refugee and human rights law.
• Calvo Doctrine emphasises national treatment and local remedies.
• Diplomatic protection may be exercised by the alien’s State of nationality.
• The essential principle is:

A State may regulate and control aliens within its territory, but it must treat them consistently with the minimum standards and other obligations imposed by International Law.

Conclusion

The treatment of aliens represents a balance between territorial sovereignty and international protection of individuals. A State has substantial authority to determine who may enter its territory, regulate the residence and activities of foreign nationals, apply its criminal and civil laws, and expel aliens in accordance with its domestic legal system. However, this authority is subject to International Law. Aliens must receive the applicable international minimum standard of treatment and benefit from fundamental protections against arbitrary detention, serious mistreatment, denial of justice and unlawful deprivation of property. Modern human rights law has further strengthened the protection available to foreign nationals, while refugee law imposes additional restrictions through the principle of non-refoulement. An alien may also receive consular assistance from their State of nationality and, where the requirements are satisfied, become the subject of diplomatic protection. The traditional international minimum standard and the Calvo Doctrine represent important approaches in the historical development of this subject. Ultimately, International Law seeks to preserve the State’s sovereign authority over aliens while ensuring that foreign nationals receive fair, lawful and internationally acceptable treatment.