Definition
Immigration laws are the body of federal statutes, regulations, and administrative rules governing who may enter the United States, under what conditions, for how long, and on what basis a non-citizen may remain, work, or acquire permanent residence or citizenship. Immigration law also defines the grounds on which a non-citizen may be removed or excluded.
The field encompasses several distinct subject areas:
1. Admissibility and entry: The standards by which foreign nationals are permitted to enter the United States, including visa categories, ports of entry, and inspection procedures.
2. Grounds of inadmissibility and deportability: Statutory bars to admission or continued presence, including criminal history, public charge risk, health-related grounds, national security concerns, and prior immigration violations.
3. Nonimmigrant status: Temporary classifications permitting entry for specific purposes and durations — tourism, study, employment, diplomatic functions, and others.
4. Immigrant status and lawful permanent residence: Pathways to indefinite authorized residence, primarily through family relationships, employment sponsorship, refugee or asylum status, and diversity programs.
5. Removal proceedings: The administrative and judicial process by which the government seeks to compel a non-citizen's departure.
6. Naturalization: The process by which a lawful permanent resident may acquire United States citizenship.
Immigration law in the United States is almost entirely federal in origin. The primary governing statute is the Immigration and Nationality Act (INA), first enacted in 1952 and extensively amended, most significantly in 1965, 1986, 1990, and 1996. Administrative authority is divided principally among the Department of Homeland Security (through U.S. Citizenship and Immigration Services, Immigration and Customs Enforcement, and Customs and Border Protection) and the Department of Justice (through the Executive Office for Immigration Review).
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Common Confusion
Immigration law is frequently conflated with nationality law and citizenship law, though these are distinct. Nationality law concerns the legal bond between an individual and a state; citizenship law defines the rights and obligations flowing from that bond. Immigration law governs movement and status for those who are not yet citizens or nationals. The three bodies of law overlap substantially in the INA but remain analytically separate. Similarly, deportation (removal of a person already present) and exclusion (denial of entry at the border) were historically distinct proceedings; post-1996 amendments consolidated them under the unified concept of "removal," but older sources use the earlier terminology and researchers must account for the shift.
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Recognized Forms
/SUBTYPES
Immigration law operates across several recognized regulatory frameworks:
- Nonimmigrant visa categories (temporary status by purpose: B-1/B-2 visitor, F-1 student, H-1B specialty occupation worker, J-1 exchange visitor, and others)
- Immigrant visa categories (permanent residence through family preference, employment preference, diversity lottery, and humanitarian protection)
- Humanitarian protection (asylum, refugee admissions, Temporary Protected Status, withholding of removal)
- Employer-based compliance (Form I-9 employment eligibility verification, E-Verify participation, anti-discrimination obligations under the INA)
- Removal and relief from removal (cancellation of removal, voluntary departure, adjustment of status, prosecutorial discretion)
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Why It Matters in Research
Immigration law is one of the most heavily amended areas of federal statutory law. Researchers working in historical sources will encounter a patchwork of superseded terminology, restructured agencies, and replaced statutory frameworks that can generate serious confusion if not navigated carefully.
Before 1952, immigration was governed by a series of discrete statutes rather than a unified code — the Immigration Act of 1917, the Immigration Act of 1924, and various quota laws among them. Bouvier's and other pre-INA dictionaries describe a system that no longer exists in its original form. References to "public charge," "moral turpitude," and exclusion on health grounds in those sources correspond to provisions that survive in modern law but have been substantially reinterpreted by administrative practice and judicial decision.
Agency terminology is a particular trap. Prior to the Homeland Security Act of 2002, the Immigration and Naturalization Service (INS) administered immigration functions within the Department of Justice. Post-2003 sources refer to DHS components. Any research bridging that period must track the agency transition carefully.
The 1996 Illegal Immigration Reform and Immigrant Responsibility Act (IIRIRA) restructured removal proceedings, replaced "deportation" and "exclusion" with the unified "removal" framework, and dramatically expanded mandatory detention and bars to relief. Sources predating 1996 describe a procedural landscape that was fundamentally altered.
For employment-related immigration research, the corpus connections between administrative immigration structure and employer obligations are direct: the employer sanctions regime created by the Immigration Reform and Control Act of 1986 (IRCA) sits at the intersection of immigration law and employment law and requires consulting both encyclopedia threads.
State and local immigration-related laws present a federalism dimension. While core immigration authority is federal, states have enacted laws affecting employment eligibility verification, licensing, and law enforcement cooperation. Researchers must distinguish between permissible state regulation and field-preempted interference with federal immigration law.
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Historical Dictionary Support
Bouvier's Law Dictionary defines immigration laws as congressional enactments regulating entry into the United States and catalogues the exclusion grounds operative at the time of publication: "all idiots, insane persons, paupers, or persons likely to become a public charge, persons suffering from a loathsome or dangerous contagious disease, persons who have been convicted of a felony or other infamous crime or misdemeanor involving moral turpitude, polygamists, and persons assisted." This list reflects the exclusion framework of the late nineteenth and early twentieth centuries, particularly the Immigration Acts of 1882 and 1917.
Bouvier's entry is useful as a snapshot of the exclusion-focused model that dominated early American immigration law — a model premised on keeping out those deemed economically, morally, or physically unfit — but it captures none of the quota system introduced in 1921 and 1924, the refugee frameworks developed after World War II, or the preference system that replaced national-origin quotas after 1965. Researchers should treat Bouvier's as a period source rather than a structural guide to modern law.
The "moral turpitude" ground catalogued in Bouvier's remains in the INA to this day, making it one of the more durable threads connecting historical and modern immigration law — though its interpretation has been extensively litigated and cannot be assumed stable across periods.
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Jurisdictional Note
Immigration law is federal. States may not establish independent immigration admission or removal regimes. However, states and localities retain authority over matters that intersect with immigration, including certain licensing requirements, law enforcement cooperation agreements (287(g) programs), and employment verification mandates, within limits set by federal preemption doctrine. The line between permissible state regulation and preempted state action has been contested in significant litigation.
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Encyclopedia Cross-Reference
The Law Mind Administrative Law & Government Encyclopedia: Immigration Law — Administrative Structure of the Immigration System
The Law Mind Employment & Labor Law Encyclopedia: Employer Obligations under Federal Immigration Law
The Law Mind Employment & Labor Law Encyclopedia: State and Local Immigration-Related Employment Laws
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