Alien Definition: What The Constitution Really Means

The term alien is used in the US Constitution to refer to any individual who is not a citizen or national of the United States. This term is synonymous with foreign national and includes those who have entered the country unlawfully. The US Constitution grants certain protections to aliens, including due process rights under the Fifth and Fourteenth Amendments. The Alien Enemies Act, enacted in 1798, is a wartime authority that allows the president to detain or deport citizens of enemy nations without a hearing. The term alien is also used in other countries' legal systems, such as the United Kingdom, where it is defined as a person who is not a British citizen or has certain other affiliations.

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The legal definition of an alien

The term "alien" has been used in US law since 1790, featuring in the Naturalization Act and later the Alien and Sedition Acts of 1798. The Alien Enemies Act, enacted during a time of war in 1798, grants the president the authority to detain or deport citizens of an enemy nation without a hearing, based solely on their country of birth or citizenship. This act has been invoked during major conflicts, such as World Wars I and II, and has been subject to abuse, raising concerns about constitutional rights and equal protection.

In US constitutional law, aliens are afforded certain protections, such as due process of law under the Fifth and Fourteenth Amendments, even if their presence in the country is unlawful. Supreme Court cases like Yamataya v. Fisher (1903) and Shaughnessy v. United States ex rel. Mezei (1953) have affirmed the rights of aliens, including the right to a hearing before deportation and protection from unlawful deprivation of life, liberty, or property.

The Alien Registration Act of 1940 mandated registration and fingerprinting for all aliens in the US over the age of 14, demonstrating the government's broad power to regulate immigration. However, this act also precluded more severe state regulations that may have been burdensome to aliens. Congress has also provided that lawfully admitted resident aliens who become public charges due to circumstances after their entry are entitled to equal benefits under the law.

While the term "alien" is not used in federal statutes in Canada, the equivalent term is "foreign national," defined as "a person who is not a Canadian citizen or a permanent resident, including a stateless person." In the United Kingdom, the British Nationality Act of 1981 defines an alien as an individual who is not a British citizen, an Irish citizen, a Commonwealth citizen, or a British protected person. In Australia, Aboriginal Australians cannot be considered aliens under the Constitution, regardless of their birthplace or citizenship status.

The Alien Enemies Act

The Act has been invoked three times during major conflicts: the War of 1812, World War I, and World War II. During World Wars I and II, the law was a key authority behind detentions, expulsions, and restrictions targeting German, Austro-Hungarian, Japanese, and Italian immigrants based solely on their ancestry. The law is best known for its role in the Japanese internment, a shameful part of US history for which Congress, presidents, and the courts have apologized.

The president may invoke the Alien Enemies Act in times of "declared war" or when a foreign government threatens or undertakes an "invasion" or "predatory incursion" against US territory. The Constitution grants Congress, not the president, the power to declare war. Therefore, the president must wait for democratic debate and a congressional vote to invoke the Act based on a declared war.

The Act raises serious concerns about the Constitution's guarantees of equal protection and due process. It also raises concerns under US laws implementing the 1967 Refugee Protocol and Convention Against Torture, as well as constitutional separation-of-powers theories that limit the authority Congress can delegate to the president.

In March 2025, President Trump invoked the Alien Enemies Act to detain and deport Venezuelans allegedly associated with the Tren de Aragua gang. A federal judge in Texas later ruled that the invocation was unlawful.

Immigration laws and rights

The term "alien" refers to any individual who is not a citizen or national of the United States, as outlined in the Immigration and Nationality Act (INA). This encompasses both documented and undocumented immigrants, as well as those with specific statuses like refugees or asylees. While the Constitution does not grant foreigners the right to enter the country without following the proper channels, it does safeguard their human rights once they are physically present in the United States.

The United States has a long history of immigration laws and policies, starting with the first statute in 1875 that excluded convicts and prostitutes from entering the country. Over the years, various exclusions and quotas based on nationality, health, criminal history, and other factors have been implemented and revised. The Chinese Exclusion Act of 1882, for example, was not repealed until 1943. The Immigration and Nationality Act of 1952 remains the foundational legislation, despite undergoing numerous significant revisions.

Congress holds the primary authority to establish immigration laws and regulations, and it has enacted statutes like the Alien Registration Act of 1940, which mandated registration and fingerprinting for all aliens over the age of 14. This Act, along with other immigration and naturalization laws, forms a uniform system for regulating aliens. Congress also has the power to prescribe the terms and conditions for aliens' entry and continued residence in the country.

While the states cannot directly contradict federal immigration laws, they do have some regulatory power over aliens' conduct and rights within their jurisdictions. For instance, states can determine the right of aliens to hold real property, and some have enacted statutes restricting aliens from owning or acquiring such property. Additionally, states can confer additional rights on aliens, as long as these rights align with legitimate state interests.

In terms of rights, the Supreme Court has affirmed that the Constitution protects everyone within the United States, regardless of their immigration status. This includes undocumented immigrants, who are still entitled to many constitutional rights. The Fifth Amendment guarantees due process rights, ensuring that no person shall be deprived of life, liberty, or property without due process of law. The Fourteenth Amendment further emphasizes equal protection under the law, regardless of immigration status. These protections have been extended to immigration proceedings, where individuals facing deportation have the right to a fair hearing, legal representation, and the presentation of evidence.

The Sixth Amendment guarantees the right to legal counsel for criminal defendants, and this includes undocumented immigrants facing criminal charges. Additionally, the Fourteenth Amendment has been interpreted to grant a right to education for undocumented children, as denying them access to public education was deemed more harmful to society.

In conclusion, while the United States has a complex immigration system with various laws and regulations, the Constitution extends certain fundamental rights and protections to all individuals within its borders, regardless of their citizenship status. These rights include due process, equal protection, access to legal counsel, and education for children.

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State laws and their limitations

In the United States, the term "alien" is synonymous with a foreign national, referring to any person who is not a citizen or national of the country. The term also encompasses organisations or corporations that are not creations of local state law.

State laws concerning aliens in the United States are subject to limitations imposed by the Constitution and Congress. While states cannot add to or detract from the conditions imposed by Congress on the admission, naturalisation, and residence of aliens, some state regulations dealing with aliens are permitted.

For example, the Alien Registration Act of 1940 provided for the registration and fingerprinting of all aliens in the United States over the age of 14, with willful failure to comply constituting a criminal offense. This uniform regulation precluded more severe or burdensome state regulations. In Hines v. Davidowitz, the Court voided a Pennsylvania law that went beyond federal requirements by mandating the acquisition of an alien identification card that had to be carried at all times.

Similarly, state laws that impose discriminatory burdens on the entrance or residence of aliens lawfully within the United States conflict with Congress's power to regulate immigration and have been held invalid. In this regard, the Supreme Court has extended constitutional protections to all aliens within the country, regardless of their legal status, guaranteeing them due process of law under the Fifth and Fourteenth Amendments. This includes the right to notice and a fair hearing before deportation, as established in cases such as Yamataya v. Fisher and United States ex rel. Vajtauer v. Comm’r of Immigration at Port of N.Y.

However, the Alien Enemies Act of 1798 serves as an exception, granting the president wartime authority to detain or deport the natives and citizens of an enemy nation without a hearing, based solely on their country of birth or citizenship. While this law has been invoked during major conflicts, its peacetime use is controversial and subject to legal challenges.

The deportation process

The term "alien" in the US Constitution refers to any individual who is not a US citizen and is present in the country. The Constitution grants certain rights and protections to aliens, including due process of law, regardless of their legal status. The deportation process for aliens in the United States is complex and can vary depending on individual circumstances. Here is an overview of the deportation process:

Identification and Detention

The identification of unregistered illegal aliens is the first step in the deportation process. The government may initiate deportation proceedings upon identifying individuals who are unlawfully present in the country or who have violated the terms of their admission. In some cases, aliens may be detained during their removal proceedings, particularly if they pose a threat to national security or public safety, or have committed specified crimes.

Notice and Hearing

Aliens facing deportation are entitled to due process, which includes the right to notice and a fair hearing. This means that they must be informed of the charges or reasons for their deportation and given an opportunity to present their case before an immigration judge. The hearing must be conducted fairly, and deportation must be based on valid evidence.

Judicial Review

If an alien facing deportation believes that their rights have been violated or that the deportation decision was made in error, they may seek judicial review by filing an appeal or a petition for a writ of habeas corpus. The judicial system provides an opportunity to correct any procedural errors or violations of due process rights.

Voluntary Departure

In some cases, the government may encourage aliens who are unlawfully present in the United States to voluntarily depart as soon as possible. This can be done through international agreements, assistance programs, or other measures that facilitate their return to their country of origin.

Execution of Deportation

Once deportation orders are finalized and all legal avenues have been exhausted, the physical removal of the alien from the United States is carried out. This may involve coordination between various government agencies, such as the Department of Homeland Security and the Department of State, to ensure the safe and efficient execution of deportation orders.

It is important to note that the deportation process can be complex and may vary depending on individual circumstances, the severity of any crimes committed, and the discretion of the immigration authorities and courts. The process can also be influenced by changing political and legislative landscapes, as well as international agreements and human rights considerations.

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