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Introduction to Immigration Law - Module 1 of 5

Module 1: Introduction to Immigration Law

Origins of Immigration Law

As long as nation-states have drawn borders, they have contended with immigration and its effects on society. Questions of who is and is not a citizen and by what criteria, and who has the right to enter a country, are central to a sense of national identity. The dismemberment of the western Roman empire by migrating Germanic tribes is a well-known example of the consequences of uncontrolled immigration, but it is not the only one.  

In ancient times, mass migrations of entire peoples made issues of immigration policy and border enforcement indistinguishable from those of national defense – and their resolutions were often military in nature, either passive (such as constructing fortifications like China’s Great Wall or Hadrian’s Wall in England) or active (such as using the army to stop or kill border crossers). Today, except in rare circumstances, using armies and fortifications as instruments of immigration policy has given way to immigration laws, the government agencies tasked with upholding them and the courts.

American historical and cultural development is inextricably intertwined with immigration. To study immigration law in the American experience is to do more than examine various types of visas, statutes and court cases. It provides a glimpse into perhaps the most important engine of demographic, social, creative and economic vitality that has, within three centuries, catapulted the United States from a collection of former English colonies clinging to the edge of a wild continent into one of the preeminent societies on Earth today. Moreover, immigration is already shaping what kind of society America will be in the future.

“Demography is destiny."

Aside from providing the framework under which foreigners can legally enter into another country and what they can do there, immigration law can affect a country’s population size, demographic composition and even its long-term viability. Although the global population is still increasing, it is not increasing uniformly. For example, in many countries, mostly European, but Japan as well, the fertility rate has declined so much that the countries face the prospect of having too few workers supporting a rapidly increasing elder population, with the negative economic and social ramifications that go along with these changes.[1]

For some countries, the problem is even worse: Germany, Japan, and Russia all have a combination of restrictive immigration and naturalization policies, aging populations and low birth rates that, by 2050, could see them experience population declines of at least 10 percent: in real numbers this means 10 million, 19 million and 23 million fewer people respectively.


Immigration and United States Population Growth


The United States is not exempt from issues of a low fertility rate and aging populace. According to the Centers for Disease Control, since 1971, the United States’ fertility rate has been less than what is needed to sustain its population; the US birth rate in 2017 was the lowest in 30 years.[2] By the mid-21st Century, the number of Americans aged 65 and older will more than double, and they will outnumber those of age 14 or younger. Yet, while some countries will experience population declines, from 2010 to 2050 the total American population in expected to increase by nearly 90 million. 

Two factors account for these growth versus decline outcomes: America’s relative desirability as an immigrant destination coupled with its comparatively liberal immigration laws and policies.


-       From 2000 to 2014, nearly 19 million new immigrants (including those who came without permission) arrived in the United States. From 2010 to 2014, immigration accounted for almost 90 percent of US population growth.

-       In 2014, more than 42 million immigrants (authorized and unauthorized) were living in the United States, comprising more than 13 percent of the American population – the highest percentage of immigrants in almost a century. Taken together with their children, the immigrant population numbers more than 86 million, or a little more than a quarter of the US population.[3]


-       The number of foreign-born people living in the U.S. is expected to increase to nearly 70 million by the year 2060, at which time they will comprise 17 percent of the population – surpassing the current record of 15 percent set in 1890. By the year 2030, immigration will become the primary source of America’s population growth.[4]

The number of people living in the United States who were not born in this country is four times that of Germany, the country with the second-highest total.[5] Presently the top five countries of origin for immigrants into the United States were:

-       Mexico, accounting for 28 percent of immigrants

-       China, 5 percent

-       India, 5 percent

-       Philippines, 4 percent

-       Korea, 3 percent.[6]

Annually, the U.S. takes in more than a million legal immigrants.[7] Not all immigrants in the U.S. come here legally, although estimating their annual numbers is difficult because it is inconsistent. For example, depending on the source and the calculation methodology used, in 2016 of 1.8 million total immigrants anywhere from 400,000 to 800,000 did not enter legally.   

Estimates as to the total number of foreigners present in the country without authorization range from about 11 million on the low end[8] to double that number on the high end.[9] Approximately half of illegal arrivals into the United States entered without inspection, with the other half consisting of individuals who came to the country legally on temporary status but who have stayed past the expiration of that status.[10]

Sources of United States Immigration Law

One of the unique characteristics of the American civilization is that its origin as a nation of immigrants distinguishes it from common citizenship qualifications in most other countries. Being or becoming an American citizen does not depend on any tribal, ethnic, religious or other sociographic prerequisites. For example, we can speak of “the American people” but there is no such thing as “the American race.” A person can be born an American or can become an American through naturalization without regard to any consideration other than adherence to the requirements of US citizenship laws. Similarly, lawful entry into and remaining in the United States as a foreign person are subject to compliance with American immigration laws. The remainder of this module explores the underpinnings of these immigration laws.

The Constitution of the United States is the ultimate source document for all US federal law, but it does not specifically refer to immigration. Instead, Section 8 of Article I of the Constitution provides the following broad instruction:

The Congress shall have power to... establish a uniform rule of naturalization…

Additional Constitutional guidance comes from Section 1 of the 14th Amendment, which extends US citizenship to “all persons born or naturalized in the United States.” This constitutional provision confirms citizenship based on naturalization but does not relate to immigration.

Until 1875, the regulation of immigration into the US fell to the individual states under the 10th Amendment to the Constitution, which leaves to the states any powers that the Constitution does not expressly give to the federal government. In that year, Congress enacted the first federal immigration law, the Page Act of 1875,[11] restricting immigration by Chinese women suspected of entering the country as prostitutes. The Chinese Exclusion Act of 1882[12] expanded the Page Act to exclude Chinese laborers as well.

Federal Supremacy

The lack of express constitutional guidance on immigration led federal courts considering immigration cases to look for indirect bases for constitutional authority. These included the Commerce Clause, the Migration and Importation Clause and the War Power Clause. It was not until 1889 that the Supreme Court finally decided that the source of federal authority over immigration lay in the principle of "national sovereignty.” Under this legal theory, control over immigration is fundamental to national sovereignty and self-definition. The Constitution, which establishes the United States of America, is therefore the source of federal immigration authority because it establishes national sovereignty.

In the case of Chae Chan Ping v. United States,[13]  the Supreme Court held that the federal government holds sole authority when it comes to excluding foreigners to the United States. More importantly, the Court also held that national sovereignty means that immigration law authority rests solely with the federal government. Later, in Fong Yue Ting v. United States,[14]  the Court held that the federal government also held sole authority to remove foreign nationals from the United States.

Despite the supremacy of federal law, some states and municipalities have passed their own laws on the subject. The motivations for these apparent challenges to federal supremacy vary: some seek to protect people in the country illegally from removal, while in at least one case, frustration with perceived lack of federal interest in enforcing federal immigration law led a state to seek its own enforcement remedies.

While the federal government’s exclusive authority over immigration law has never been successfully challenged in court, cities and states have, at times, enacted their own ordinances and laws that prohibit local and state officials from enforcing federal immigration laws or cooperating with federal efforts to enforce those laws. These so-called “sanctuary” laws adhere to the concept of “nullification,” the argument that states have the right to refuse to enforce federal laws that, they believe, are unconstitutional.

Sanctuary laws will typically include one or more of the following restrictions:

-       Not allowing police officers or other officials to ask individuals about their immigration status;

-       Not allowing those same officers and officials to report to federal officials the identities of people in their jurisdictions whose immigration status they suspect is illegal; or

-       Not allowing unlawfully present foreigners who have committed crimes and are being held in local custody to be transferred to the custody of federal immigration officials.

For example, Oregon’s sanctuary law, adopted in 1987, prohibits state and local law enforcement personnel from using any resources (money, personnel or equipment) to locate or apprehend “…persons whose only violation of law is that they are persons of foreign citizenship present in the United States in violation of federal immigration laws.”[15]

Although the US Supreme Court has rejected the argument of nullification in the context of slavery in 1858[16] and school racial integration in 1958,[17] immigration-related nullification laws have proliferated in recent years, from fewer than 11 before 2000 to more than 500 today.[18] In many of these places, sanctuary laws have gone unchallenged by federal authorities. In California, attempts by the Justice Department and some local officials to contest in court the validity of that state’s sanctuary law produced mixed results.[19] [20] The Supreme Court has yet to decide upon a sanctuary nullification law case, and until it does, the present uncertainty about the legal effect of these laws is likely to persist.


Parallel State Immigration Laws

Another challenge to exclusive federal immigration law authority can occur when a state creates its own immigration laws. The most notable example of this happened in Arizona, which passed its own immigration law in 2010 that, among other things, made it a misdemeanor under state law to be in Arizona as an illegal immigrant. The law also authorized state and local law enforcement officials to enforce federal immigration laws.[21]

The Supreme Court invalidated most of that law in the case of Arizona v. United States,[22] holding that all but one of its key provisions were preempted by federal law. The Court declined to hold unconstitutional the state law’s authorization for police to check someone’s immigration status while they are enforcing other laws, if they have reasonable suspicion that the person is in the United States illegally.

Federal Legislation

The first significant federal law governing immigration was the Immigration Act of 1882. Unlike the Page Act of 1875 and the Chinese Exclusion Act of 1882, the Immigration Act of 1882 did not preclude immigration from any specific country or geographic region. Instead it sought to promote or to limit immigration based on characteristics that showed desirability of the immigrant or lack thereof. Specifically, the Act authorized immigration authorities to preclude entry into the U.S. by people who were mentally ill, had a non-political criminal history or would be likely to become dependent on public assistance. It also imposed a head tax on people immigrating to the country, the proceeds of which funded the governmental apparatus needed to enforce it.

The Immigration Act of 1891[23] expanded the Immigration Act of 1882 to add additional classifications of excludable foreigners and established jurisdiction to regulate immigration across the U.S. borders with Mexico and Canada (the 1882 Act applied only to maritime ports of entry). It also established within the Department of the Treasury the first federal immigration agency, the Office of Superintendent of Immigration. Subsequent legislation up to 1952 consisted of several laws that, among other things, added more kinds of people barred from immigration, established the Bureau of Immigration and Naturalization, and imposed numerical limits on immigration.

The Immigration and Nationality Act of 1952[24] was the next major legislation to affect immigration. It was the first comprehensive immigration law in the United States, ending the prior practice of passing legislation on a piecemeal basis to modify earlier statutes. This Act ended the use of race-based restrictions, introduced a three-part classification for immigrants (those subject to numerical quotas, those exempt from quotas and refugees) and established procedures for non-citizens to become naturalized citizens.[25]

The Immigration and Nationality Act of 1965[26] ended the practice of using national origin-based immigration quotas, which, together with the earlier removal of race-based quotas marked a major shift in U.S. immigration demographics away from Europe. Whereas, through the 1950s, nearly 70 percent of immigrants were European, the Act created a new mix of almost 50 percent from South and Central America, another 35 percent from Asia.

The Immigration Reform and Control Act of 1986,[27] in part, attempted to cope with the large increase in the number of people entering the United States illegally after passage of the 1965 Act. It added penalties for employers who hired illegal aliens, but what it is probably most remembered for is its amnesty provision: approximately 2.7 million people living in the U.S. illegally were able to obtain citizenship via amnesty as a result of its enactment.  

The Immigration Act of 1990[28] raised the number of legal immigrants to 675,000 annually, beginning in 1995. It also introduced new categories of work visas and introduced the “visa lottery” system for immigrants from countries that had low levels of immigration into the U.S.

The Illegal Immigration Reform and Immigrant Responsibility Act of 1996[29] imposed restrictions on the abilities of illegal aliens to remain in the United States. It also authorized the construction of barriers on the U.S.-Mexico border, and made it easier to remove illegal aliens for committing lesser criminal offenses than had previously made immigrants subject to deportation.

The Homeland Security Act of 2002[30] consolidated the functions of the former Immigration and Naturalization Service (which had oversight of immigration matters from its creation in 1933) into the newly-created Immigration and Customs Enforcement agency under the Department of Homeland Security.

Not all policies affecting immigration come from legislation, as executive orders have their roles as well. Of particular note is the Deferred Action for Childhood Arrivals (“DACA”), which is based on a 2012 executive memorandum under the administration of President Barack Obama. DACA allows people who were children of illegal aliens at the time they entered the United States to be eligible for work permits and to have deportation proceedings against them deferred. Although DACA expired as of March 2018, as of December 2018, the program effectively remains in place pending the outcome of litigation over its constitutionality.

In the next module, we will examine in detail how U.S. immigration law affects immigrants who seek to enter the country on a temporary basis (that is, those who are not seeking permanent residency or status as naturalized citizens).


[16] Ableman v. Booth, 62 U.S. 506 (1858)

[17] Cooperv. Aaron, 358 U.S. 1 (1958)

[22] Arizona v. United States, 567 U.S. 387 (2012) https://supreme.justia.com/cases/federal/us/567/387/