(From Grolier Multimedia Encyclopedia)

Illegal Immigration

Since the 15th century, governments have considered the control of their borders to lie at the heart of sovereignty. During the last third of the 20th century, that control became increasingly difficult for many countries in the world. By 2002 the total number of illegal aliens in Europe was more than 3 million; by 2007 there were an estimated 12 million illegal immigrants in the United States.

The United States is a magnet for migration from all over the world. It is a large country with a successful continental economy. It has two long borders with many points of entry and many international airports. It does not have a strict system of internal control for foreign nationals, as do several other countries. A little more than half of the illegal aliens in the United States entered without inspection; the rest are tourists, students, or others who overstayed their temporary visas. This is somewhat unsurprising since the United States admits more than 25 million persons annually on such visas.

Although some illegal aliens are skilled and educated, most of them are poor. As seen in the study of nearly 3 million aliens legalized under the Immigration Reform and Control Act of 1986, more than 85% of them were from Latin American countries. Only 28% of those more than 24 years of age were high-school graduates, compared to 78% of native Hispanic Americans. Of the amnestied adults, 55% had never entered high school. By 1991, median yearly individual earnings for these legalized workers were 26% below those of all U.S. workers. Except in times of high prosperity, most of them compete for low-paying jobs with segments of the least skilled of the U.S. population.

Early U.S. Illegal Immigration

Until recent decades, there had been only sporadic and often inefficient enforcement to limit the presence of illegal aliens in the country. During World War II, Mexican contract laborers were imported to meet a shortage of agricultural workers. Most of them were part of the so-called bracero program, which did not end until 1964. This program increased migration consciousness among Mexicans and Central Americans. The opportunity to earn money for their families was tremendously tempting; many undocumented workers followed the crops in the western states. Although they usually returned home, some illegal immigrants settled in the U.S. interior, even as far away as Chicago. Illegal migration was abetted by the enforcement tactics of the Immigration and Naturalization Service (INS; since 2003, U.S. Citizenship and Immigration Services, or USCIS). The INS often cooperated with agricultural employers, forgoing searches and deportations when employers perceived a shortage of farmworkers. In 1952 the U.S. Congress made it illegal to "harbor, transport, or conceal illegal entrants." But agricultural growers in Texas and elsewhere made certain that Congress excluded employment from the definition of "harboring." This provided a loophole for growers and others who knowingly employed illegal aliens. Congress also starved the INS budget, thereby limiting effective enforcement.

Deterrents to Illegal Immigration

In 1981, Congress's Select Commission on Immigration and Refugee Policy (1979–81) urged an end to the ambiguity inherent in the prevailing enforcement strategy by terminating the so-called Texas Proviso. In passing the Immigration Reform and Control Act, Congress agreed that undocumented workers sometimes displace American workers and depress labor standards and wages. It called for sanctions against employers who knowingly and willfully hire illegal aliens. But employer sanctions have proved extremely difficult to enforce. The key problem is the absence of a reliable, universal system of identifying new hires who are eligible to work. It is still fairly easy to obtain fraudulent documents, and employers are bound under the law to accept documents that appear to be valid. In 1997 the INS estimated that about 3% of U.S. employers, some 195,000, hired undocumented workers.

To deal with this problem, among others, Congress implemented the U.S. Commission on Immigration Reform (1991–97). This body recommended, in 1994, legislation establishing a computerized registry to determine whether or not a prospective employee is eligible to work. The current system is based on matching the verified social security number of the applicant with official records. In 2002 the Social Security Administration sent out an estimated 750,000 letters to employers notifying them of problems matching their employees names with the social security numbers given.

Deterring illegal migration poses a major problem for free, democratic societies such as the United States. This is partly because of the concern Americans have for privacy rights. Another factor is the reluctance of employers to accept more regulation. Perhaps the most important reason, however, is that there is a great demand in times of prosperity for illegal aliens. Examples of such needs include housekeepers in Atlanta; hospital workers in Chicago; day-care givers in New York; short-order cooks in Boston; meatpackers in Nebraska; construction workers in Utah; or agricultural employees in California, Texas, Oregon, and elsewhere. A Department of Labor survey in 2002 showed that undocumented immigrants made up more than one-third of the U.S. agricultural workforce. They were also employed in significant numbers in the construction, garment, and food industries.

Although work-site enforcement is still extremely difficult, efforts to deter illegal migration at the borders and other ports of entry appear to have been increasingly effective in recent years. The financial resources available to the INS grew from $1.5 billion in fiscal year 1994 to $9.5 billion in fiscal year 2006. The Commission on Immigration Reform estimated that approximately 59% of all illegal aliens in 1996 came into the country without inspection. New technology employed by the U.S. Border Patrol has been used effectively. Additionally, the Border Patrol has some 12,000 agents on its staff. But no matter how advanced the technology at the border becomes, or how many agents patrol it, the motivation to migrate remains strong. So great is that motivation that the smuggling of migrants has become a major international business. Migrants will borrow money from relatives or loan sharks and in some cases work for years to pay off their debts to smugglers.

It is simply not possible to prevent everyone from crawling under barbed-wire fences or wading across rivers. Similarly, preventing every tourist, student, or temporary worker with a visa from staying beyond their authorized time is not an easy task. It is also impossible to prevent everyone who claims asylum—validly or not—from failing to appear in court to defend his or her claim. Many people from each of these groups end up as part of the illegal-alien labor market.


Once in the United States, illegal aliens are subject to apprehension and deportation, now called "removal." In 1996, Congress passed tough laws to speed the removal process. The total number of removals increased from 69,000 in 1996 to more than 148,500 in 2002. (It is important to note that in 2003 it was estimated that some 300,000 illegal aliens who had been ordered to leave were still in the country.) Most of those removed did not have criminal records but were caught at the southwest border trying to enter the country with no documents or with fake documents; in 2002 the INS removed 70,759 aliens for criminal violations. Through a process called "expedited removal," the 1996 law authorized immigration officials to deport quickly at airports and at the border any foreign national they thought to be illegal. For the first time, immigration officials—not judges—were authorized to determine which of them could be deported and barred from the United States for five years, a decision they could make quickly, without a lawyer representing the immigrant. There are many critics of the new laws. Even some USCIS officials believe that they are too broad. Some detention centers have become dangerously overcrowded, and there have been cases of aliens being badly abused in them.

Renewed Reform Efforts

Illegal immigration came to the forefront of the U.S. agenda in the early years of the second term of President George W. Bush. In November 2005, Bush announced a three-part plan for comprehensive immigration reform. The plan called for the return of illegal immigrants caught crossing the southwestern U.S. border without exception, passage of immigration-reform legislation, and steps to stop people from crossing the border.

Meanwhile, for the first time since 1986, the U.S. Congress considered immigration-reform legislation in 2006. Proposals were debated in the both the House of Representatives and the Senate, but final action on comprehensive reform was not immediately taken. However, some legislative measures passed in 2006 addressed the issue. The appropriations act for the Department of Homeland Security, which was signed by Bush on October 4, included provisions affecting illegal immigration. The legislation included nearly $1.2 billion in funding for many forms of increased border protection: additional border fencing; vehicle barriers and lighting; and new technology that features ground-based radar, infrared cameras, and advance sensors to reduce illegal border crossings. The act also provided funds for some 1,500 additional Border Patrol agents. Earlier, the Bush administration had deployed about 6,000 National Guard troops to the southern border to help train border agents.

A separate bill signed by Bush on Oct. 26, 2006, authorized the construction of 1,120 km (700 mi) of new fencing in the Southwest. The project will cover one-third of the U.S.-Mexican border.

The Senate took up the issue of illegal immigration again in 2007 but failed to pass reform legislation. The defeated measure would have granted illegal immigrants a way of gaining legal status, provided a path to citizenship through a new visa system, established a temporary worker program, and increased border security. The measure had the support of President Bush, but opponents argued that it would provide "amnesty" to illegal immigrants. The bill’s defeat meant that efforts to enact immigration reform would likely be postponed until after the 2008 U.S. presidential election.

The Problem Will Continue

The human factors involved in illegal migration will always make enforcement difficult. The vast majority of illegal aliens come to the United States to work, and not for welfare, for which they are not eligible (except for emergency medical assistance or disaster relief). They work hard, pay many taxes, and for the most part do not commit crimes. Yet their very presence is an invitation to criminality. Some of their employers violate occupational and health-and-safety rules and laws regulating wages and hours. The aliens themselves may be afraid to report their own communicable illnesses or violations of the law by others lest they be deported.

Great disparities in opportunity between populations who live in poor and/or oppressive societies and those who live in the United States remain a powerful incentive. Because of these differences, there will continue to be substantial numbers of persons who try to enter the United States illegally or who overstay their visas. Given the fact that many consumers benefit from the lower cost of their labor on such various items as supermarket vegetables, fast-food hamburgers, and new clothes and housing, the effectiveness of enforcement strategies may continue to be problematic for some time.

Lawrence H. Fuchs


Bean, Frank D., et al., eds., Undocumented Migration to the United States: IRCA and the Experience of the 1980s (1990).

Cornelius, Wayne A., et al., eds., Controlling Immigration: A Global Perspective (1995).

Hart, Dianne Walta, Undocumented in LA: An Immigrant's Story (1997).

Smith, Paul J., ed., Human Smuggling: The Chinese Migrant Trafficking and the Challenge to America's Immigration Tradition (1997).

U.S. Commission on Immigration Reform, U.S. Immigration Policy: Restoring Credibility (A Report to Congress) (1994).

Weiner, Myron, The Global International Migration Crisis: Challenge to States and to Human Rights (1995).