Alien is a legal term that refers to any person who is not a citizen or a national of the United States, as listed in the Immigration and Nationality Act (INA). There are different categories of aliens: resident and nonresident, immigrant and nonimmigrant, asylee and refugee, documented and undocumented.
According to the Immigration and Nationality Act (INA), an alien is an individual who does not have U.S. citizenship and is not a U.S. national. The INA defines a national of the United States as one who, while not a citizen, owes permanent allegiance to the United States. One owes personal allegiance to the United States if that person has taken an oath of naturalization.
Naturalization occurs when an alien applies for citizenship. They must prove a series of eligibility requirements in order for U.S. Citizenship and Immigration Services to certify the naturalization request. Without receiving naturalized citizenship, a person can live in the United States for decades without officially becoming a "national."
For individuals who possess citizenship at one time but later renounce their citizenship, renunciation renders those individuals aliens. Renouncing one's citizenship requires taking a formal oath of renunciation. After renouncing, such persons can either pledge allegiance to another country or can declare themselves "world citizens."
One who alleges alienage bears the burden of proving the claim by a "clear and satisfactory" standard, and the claimant must prove the alienage successfully to initiate a deportation proceeding. To issue a deportation order, the court must find evidence that clearly, unequivocally, and convincingly proves alienage.
A series of classifications exist to describe aliens and their relationships to the United States. In the past the government used the terms "resident alien" and "non-resident alien," but the government has replaced these terms with "immigrant" and "non-immigrant." Some aliens also receive "refugee" or "asylee" status.
Legal immigrants enjoy the opportunity to reside within the United States without having obtained U.S. citizenship. While they have no legal or constitutional rights to remain within the country, they may stay provided that the government renews their visas at the expiration of the previous visa. In return for the U.S. granting temporary residence, these aliens owe "temporary allegiance" to the United States. Temporary allegiance involves obeying all U.S. laws while within the U.S., implied consent to U.S. court jurisdiction for alleged violation of tort and commercial laws, and submission to the court system's power of subpoena. While aliens may face suit under tort or commercial laws, they also possess the right to sue.
Despite the obligations that fall under temporary allegiance, the law affords aliens many of the rights that U.S. citizens possess. Aliens have the right to gain employment, and states cannot use discriminatory methods to protect local jobs for state citizens at the expense of aliens. Furthermore, employers cannot deprive aliens of the federal and state mandatory minimum wages.
Aliens also receive treatment very similar to the treatment that U.S. citizens receive in the context of the judicial system. For instance, the Fifth and Fourteenth Amendments of the United States Constitution apply to aliens residing within the United States. As such, the courts guarantee aliens the right to due process of law and equal protection of the laws. Courts have generally construed the Fourth Amendment as applicable to aliens as well. The Fourth Amendment prohibits the government from conducting unreasonable searches and seizures.
Congress has the preeminent power in terms of passing statutes that regulate immigration and alienage. Consequently, the United States Constitution enables Congress to delineate the rights, duties, and liabilities that accompany legal immigrant status. Congressional power in this realm, however, must comply with the qualification that any law resulting in disparate treatment between aliens and citizens must bear some relation to a legitimate goal impacting immigration law. When a law treats an alien differently from a U.S. citizen, courts treat the law as inherently suspect and apply strict scrutiny when considering the law's constitutionality.
Aliens who reside in the U.S. have certain obligations that U.S. citizens also have. These obligations include but are not limited to paying state and federal taxes. For situations in which an alien fails to abide by these obligations, the alien may retain counsel and assistance from the alien's embassy.
States possess the power to confer additional rights on aliens within their respective jurisdictions. While states may not pass regulations affecting aliens that directly conflict with federal laws or the U.S. Constitution, states may pass other regulations if they bear some rational relationship to a legitimate state interest.
State law controls the right of an alien to hold real property in the particular state. Under common law, the alien had property rights similar to those of citizens. Currently, most states have enacted statutes following the common law, but a few have forbid aliens, ineligible for U.S. citizenship, from holding or acquiring real property. These laws have resulted in some successful challenges by aliens who claimed the laws were unconstitutional.
Access to the Courts
Generally, both legal and illegal immigrants have the right to bring suit in United States federal courts. Federal civil rights statutes also expressly permit aliens to bring claims of civil rights violations in federal court. States have generally provided aliens with access to their court systems as well, provided that the alien resides within the particular state.
U.S. courts typically grant nonresident aliens the right to sue only if the cause of action arose within the United States. A series of recent U.S. Supreme Court cases, however, have determined that non-resident aliens detained by U.S. military forces may bring suit in U.S. federal court. See War Powers.
When invoking federal question jurisdiction, federal statutes provide aliens with access to the federal court system in the following three scenarios: allegations of civil rights violations by the federal government, allegations of Equal Protection Clause violations by the federal government, and allegations of violations of the Refugee Act of 1980.
Federal diversity jurisdiction permits suits in which a party commences a suit between diverse citizens with an alien as an additional named party on either or both sides of the suit. Alienage must exist at the time that the cause of action commences. If, however, a suit commences in which aliens fall on both sides of the suit but citizens fall on only one side or neither side, then diversity jurisdiction fails.
[Last updated in June of 2022 by the Wex Definitions Team]
menu of sources
Federal Material
U.S. Constitution
- Article I, Section 8 - Congressional Authority to Establish Uniform Rules of Naturalization
- CRS Annotated Constitution:
Federal Statutes
- 8 U.S.C., chapter 12 - Immigration and Nationality
- 8 U.S.C., chapter 13 - Immigration and Naturalization Service
- 18 U.S.C., Part I, chapter 69 - Nationality and Citizenship (in the context of crimes)
Federal Regulations
- 8 C.F.R. - Aliens and Nationality
Judicial Decisions
- U.S. Supreme Court:
- U.S. Circuit Courts of Appeals: Immigration Cases
International Material
Conventions and Treaties
Other References
Key Internet Sources
- Federal Agencies:
- American Immigration Law Foundation
- Immigration Equality's Immigration Law Glossary
- ITA's Immigration Law Resources
- Siskind's Immigration Bulletin
- Immigration Law (Nolo)
Useful Offnet (or Subscription - $) Sources
- Good Starting Point in Print: David S. Weissbrodt and Laura Danielson, Immigration Law and Procedure in a Nutshell, West Publishing Company, 5th ed. (2005)