Immigration and Naturalization Fundamentals
CRS Report for Congress
Immigration and Naturalization Fundamentals
Ruth Ellen Wasem
Specialist in Social Legislation
Domestic Social Policy Division
Congress typically considers a wide range of immigration issues and now that the
number of foreign born residents of the United States — 32.5 million in 2002 — is at
the highest point in U.S. history, the debates over immigration policies grow in
importance. As a backdrop to these debates, this report provides an introduction to
immigration and naturalization policy, concepts, and statistical trends. It touches on a
range of topics, including numerical limits, refugees and asylees, exclusion,
naturalization, illegal aliens, eligibility for federal benefits, and taxation. This report
does not track legislation and will not be regularly updated.
Four major principles underlie U.S. policy on legal permanent immigration: the
reunification of families, the admission of immigrants with needed skills, the protection
of refugees, and the diversity of admissions by the country of origin. These principles are
embodied in federal law, the Immigration and Nationality Act (INA) first codified in
the Enhanced Border Security and Visa Reform Act of 2002 (P.L. 107-173).
An alien is “any person not a citizen or national of the United States” and is
synonymous with noncitizen. It includes people who are here legally, as well as people
who are here in violation of the INA. Noncitizen is generally used to describe all foreign-
born persons in the United States who have not become citizens.
The two basic types of legal aliens are immigrants and nonimmigrants. Immigrants
are persons admitted as legal permanent residents (LPRs) of the United States.
Nonimmigrants — such as tourists, foreign students, diplomats, temporary agricultural
1 Other major laws amending INA are the Immigration Amendments of 1965, the Refugee Act
of 1980, the Immigration Reform and Control Act of 1986, the Immigration Act of 1990, and the
Illegal Immigration Reform and Immigrant Responsibility Act of 1996.
Congressional Research Service ˜ The Library of Congress
workers, exchange visitors, or intracompany business personnel — are admitted for a
specific purpose and a temporary period of time. Nonimmigrants are required to leave the
country when their visas expire, though certain classes of nonimmigrants may adjust to
LPR status if they otherwise qualify.2
The conditions for the admission of immigrants are much more stringent than
nonimmigrants, and many fewer immigrants than nonimmigrants are admitted. Once
admitted, however, immigrants are subject to few restrictions; for example, they may
accept and change employment, and may apply for U.S. citizenship through the
naturalization process, generally after 5 years.
Numerical Limits and Preference Categories
Immigration admissions are subject to a complex set of numerical limits and
preference categories that give priority for admission on the basis of family relationships,
needed skills, and geographic diversity. These include a flexible worldwide cap of
which changes yearly. Numbers allocated to the three preference tracks include a
226,000 minimum for family-based, 140,000 for employment-based, and 55,000 for
diversity immigrants (i.e., a formula-based visa lottery aimed at countries that have low
levels of immigration to the United States). The per country ceilings may be exceeded
for employment-based immigrants, but the worldwide limit of 140,000 remains in effect.
In addition, the immediate relatives of U.S. citizens (i.e., their spouses and unmarried
minor children, and the parents of adult U.S. citizens) are admitted outside of the
numerical limits of the per country ceilings and are the “flexible” component of the
Table 1. FY2001 Immigrants by CategoryThe largest number of immigrants is
Total1,064,318admitted because of family relationship to
Immediate relatives of citizens443,964a U.S. citizen or immigrant. Of the
Family preference232,1431,064,318 legal immigrants in FY2001,
Employment preference179,19564% entered on the basis of family ties.
Refugee and asylee adjustments108,506Immediate relatives of U.S. citizens made
Diversity42,506up the single largest group of immigrants,
Other58,495as Table 1 indicates. Family preference
immigrants — the spouses and children of
immigrants, the adult children of U.S. citizens, and the siblings of adult U.S. citizens —
were the second largest group. Additional major immigrant groups in FY2001 were
employment-based preference immigrants, including spouses and children, refugees and3
asylees adjusting to immigrant status, and diversity immigrants. The Bureau of
2 Nonimmigrants are often referred to by the letter that denotes their section in the statute, such
as H-2A agricultural workers, F-1 foreign students, or J-1 cultural exchange visitors. CRS Report
RL31381, U.S. Immigration Policy on Temporary Admissions, by Ruth Ellen Wasem.
3 The largest group in the “other category” are the 18,926 Nicaraguans who adjusted to LPR
status through special legislation, the Nicaraguan and Central American Relief Act of 1997.
Citizenship and Immigration Services (BCIS) in the Department of Homeland Security
(DHS) is the lead agency for immigrant admissions.4
Refugees and Asylees
Refugee admissions are governed by different criteria and numerical limits than
immigrant admissions. Refugee status requires a finding of persecution or a well-founded
fear of persecution in situations of “special humanitarian concern” to the United States.
The total annual number of refugee admissions and the allocation of these numbers
among refugee groups are determined at the start of each fiscal year by the President after
consultation with the Congress. Refugees are admitted from abroad. The INA also
provides for the granting of asylum on a case-by-case basis to aliens physically present
in the United States who meet the statutory definition of “refugee.”5
Exclusion and Removal
All aliens must satisfy State Department consular officers abroad and DHS Bureau
of Customs and Border Protection inspectors upon entry to the U.S. that they are not
ineligible for visas or admission under the so-called “grounds for inadmissibility” of the
INA. These criteria categories are:
!national security and terrorist concerns;
!public charge (e.g., indigence);
!seeking to work without proper labor certification;
!illegal entrants and immigration law violations;
!lacking proper documents;
!ineligible for citizenship; and,
!aliens previously removed.
Some provisions may be waived or are not applicable in the case of nonimmigrants,
refugees (e.g., public charge), and other aliens. All family-based immigrants entering after
December 18, 1997, must have a new binding affidavit of support signed by a U.S.
sponsor in order to meet the public charge requirement.
The INA also specifies the circumstances and actions that result in aliens being
removed from the United States, i.e., deported. The category of criminal grounds has
been of special concern in recent years, and the Illegal Immigration Reform and
Immigrant Responsibility Act of 1996 expanded and toughened the deportation
consequences of criminal convictions. The category of terrorist grounds has also been
broadened and tightened up by the USA Patriot Act of 2001. (P.L. 107-77).
4 Other agencies with primary responsibility for immigration functions are the Bureau of Customs
and Border Protection and the Bureau of Immigration and Customs Enforcement, both in DHS.
See CRS Report RS21504, Immigration-Related Funding in the President’s FY2004 Budget
Request, by Karma Ester.
5 CRS Report RL31269, Refugee Admissions and Resettlement Policy, by Andorra Bruno.
Figure 1. Annual Immigrant Admissions andStatistical Trends
Status Adjustments, 1900-2001
1,400The annual number of LPRs
admitted or adjusted in the
1,200United States rose gradually after
1,000World War II, as Figure 1illustrates. However, the annual
800Legalized Aliensadmissions never again reached
the peaks of the early 20th
600century. The BCIS data present
400only those admitted as LPRs or
those adjusting to LPR status.
200The growth in immigration after
01980 is partly attributable to the
1900 1905 1910 1915 1920 1925 1930 1935 1940 1945 1950 1955 1960 1965 1970 1975 1980 1985 1990 19952001total number of admissions
Source: CRS presentation of BCIS data. Aliens legalizing through the Immigration Reform and Control Act of 1986 are depicted by year of arrival.under the basic system,
consisting of immigrants
entering through a preference
system as well as immediate relatives of U.S. citizens, that was augmented considerably6
by legalized aliens. In addition, the number of refugees admitted increased from 718,000
in the period 1966-1980 to 1.6 million during the period 1981-1995, after the enactment
of the Refugee Act of 1980.
Figure 2. Foreign-Born Residents of theThe Immigration Act of 1990
United States, 1870-2002increased the ceiling on
40Millions of People40Percent of PopulationPercentPeople!immigration, with the provision
that unused employment visas
3030would be made available the
following year for family
!!!!!!There are two major
!!1010statistical perspectives on trends
!!!in immigration. One uses the
! ! !
official BCIS admissions data
1870188018901900191019201930194019501960197019801990200200and the other draws on Bureau
Source: CRS presentation of data from The Foreign-Born Population: 1994, by K. A. Hansen & A. Bachu, U.S. Bureau of Census (1995); The Population of the United of Census population surveys.
States, by Donald J. Bogue (1985); and the March 2002 Supplement of the CPS.The BCIS data present onlythose admitted as LPRs or those
adjusting to LPR status. The
census data, on the other hand, include all residents in the population counts, and the
census asks people whether they were born in the United States or abroad. As a result, the
census data also contain long-term temporary (nonimmigrant) residents and unauthorized
6 The Immigration Reform and Control Act of 1986 legalized several million aliens residing in
the United States without authorization.
The percent of the population that is foreign born, depicted in Figure 2, resembles
the trend line of annual admissions data presented in Figure 1. It indicates the proportion
of foreign born residents is not as large as during earlier periods, but is approaching
historic levels at the turn of the last century. Figure 2 illustrates that the sheer number
— 32.5 in 2002 — has more than doubled from 14.1 million in 1980 and is at the highest
point in U.S. history.
Another tradition of immigration policy is to provide immigrants an opportunity to
integrate fully into society. Under U.S. immigration law, all LPRs are potential citizens
and may become so through a process known as naturalization. To naturalize, aliens
must have continuously resided in the United States for 5 years as LPRs (3 years in the
case of spouses of U.S. citizens), show that they have good moral character, demonstrate
the ability to read, write, speak, and understand English, and pass an examination on U.S.
government and history. Applicants pay fees of $310 when they file their materials and
have the option of taking a standardized civics test or of having the examiner quiz them
on civics as part of their interview.
The language requirement is waived for those who are at least 50 years old and have
lived in the United States at least 20 years or who are at least 55 years old and have lived
in the United States at least 15 years. Special consideration on the civics requirement is
to be given to aliens who are over 65 years old and have lived in the United States for at
least 20 years. Both the language and civics requirements are waived for those who are
unable to comply due to physical or developmental disabilities or mental impairment.
Certain requirements are waived
Figure 3. Naturalization Petitions andfor those who have served in the
Approvals, FY1990 to FY2002U.S. military.
1800ThousandsPetitions filedFor a variety of reasons, the
1600number of LPRs petitioning to
1400naturalize has increased in the
-1200past year but has not reachednearly the highs of the mid-
--8001990s when over a million
-----600people sought to naturalize
-400annually, as Figure 3 depicts.
----200Petitions approvedThe pending caseload for
naturalization remains over half
19901991199219931994199519961997199819992000200120020a million, and it is not
Fiscal Yearuncommon for some LPRs to
Source: CRS presentation of Bureau of Citizenship and Immigration Services data. Note: As of September 30, 2002, a total of 623,519 cases were pending.wait 1-2 years for their petitions
to be processed, depending on
the caseload in the region in which the LPR lives.
Illegal aliens or unauthorized aliens are those noncitizens who either entered the
United States surreptitiously, i.e., entered without inspection (referred to as EWIs), or
overstayed the term of their nonimmigrant visas, e.g., tourist or student visas. Many of
these aliens have some type of document — either bogus or expired — and may have
cases pending with BCIS. The former INS estimated that there were 7.0 million
unauthorized aliens in the United States in 2000. Demographers at the Census Bureau
and the Urban Institute estimated unauthorized population in 2000 at 8.7 and 8.5 million
respectively, but these latter estimates included “quasi-legal” aliens who had petitions
pending or relief from deportation.7
Eligibility for Federal Benefits
Noncitizens’ eligibility for major federal benefit programs depends on their
immigration status and whether they arrived before or after enactment of P.L. 104-193,
the 1996 welfare law (as amended by P.L. 105-33 and P.L. 105-185). Refugees remain
eligible for Supplemental Security Income (SSI) and Medicaid for 7 years after arrival,
and for other restricted programs for 5 years. Most LPRs are barred SSI until they
naturalize or meet a 10-year work requirement. LPRs receiving SSI (and SSI-related
Medicaid) on August 22, 1996, the enactment date of P.L. 104-193, continue to be
eligible, as do those here then whose subsequent disability makes them eligible for SSI
and Medicaid. All LPRs who meet a 5-year residence test and all LPR children
(regardless of date of entry or length of residence) are eligible for food stamps. LPRs
entering after August 22, 1996, are barred from Temporary Assistance for Needy Families
(TANF) and Medicaid for 5 years, after which their coverage becomes a state option.
Also after the 5-year bar, the sponsor’s income is deemed to be available to new
immigrants in determining their financial eligibility for designated federal means-tested
programs until they naturalize or meet the work requirement. Unauthorized aliens, i.e.,
illegal aliens, are ineligible for almost all federal benefits except, for example, emergency
Aliens in the United States are generally subject to the same tax obligations,
including Social Security (FICA) and unemployment (FUTA) as citizens of the United
States, with the exception of certain nonimmigrant students and cultural exchange
visitors. LPRs are treated the same as citizens for tax purposes. Other aliens, including
unauthorized migrants, are held to a “substantive presence” test based upon the number9
of days they have been in the United States. Some countries have reciprocal tax treaties
with the United States that — depending on the terms of the particular treaty — exempt
citizens of their country living in the United States from certain taxes in the United States.
7 U.S. Immigration and Naturalization Service, Estimates of the Unauthorized Immigrant
Population Residing in the United States, 1990 to 2000, Jan. 31, 2003.
8 CRS Report RL31114, Noncitizen Eligibility for Major Federal Public Assistance Programs:
Policies and Legislation, by Ruth Ellen Wasem and Joe Richardson.
9 This “substantive presence” test is at least 31 days in the current year and 183 or more days in
the 2 prior years, according to a formula.