Updated January 16, 2019
U.S. Immigration Laws for Aliens Arriving at the Border
Introduction
criminal penalties for persons who are convicted of
In recent years, the migrant population arriving at the U.S.-
unlawfully re-entering the United States after being
Mexico (Southern) border without legal immigration status
removed from the country previously (generally classified
has shifted from being comprised predominantly of
as a felony). Foreign nationals apprehended for criminal
Mexican adult economic migrants to being comprised
immigration violations are subject to prosecution by the
primarily of Central American adults, family units (adults
Department of Justice (DOJ) in federal criminal courts.
with at least one child under age 18), and unaccompanied
children, many of whom seek asylum in the United States.
Foreign nationals who attempt to enter the United States
How they are processed and what options they have for
without authorization often do so between ports of entry on
legal admission and residing lawfully in the United States
the U.S. border. If apprehended, they are processed and
depend on how they attempt to enter the United States,
detained briefly by CBP and either transferred to the
whether they are children and/or arrive in families, what
custody of another federal agency or placed directly into
country they originate from, and if they request asylum.
removal proceedings. Procedurally, removal proceedings
occur after any criminal prosecution for illegal entry.
Aliens (foreign nationals) who wish to enter the United
States may request admission legally at a U.S. port of entry
CBP typically refers apprehended aliens to DOJ for
or may attempt to enter the United States illegally between
criminal prosecution if they meet criminal enforcement
ports of entry. The Department of Homeland Security
priorities (e.g., child trafficking, prior felony convictions,
(DHS) has broad discretion to detain aliens, including
multiple illegal entries). DOJ’s U.S. Marshals Service then
asylum seekers, during the pendency of removal
transports these individuals to DOJ criminal detention
proceedings that determine whether they are admissible or
facilities for pre-trial detention. After they have been
have other grounds to remain in the United States. Removal
tried—and if convicted, served a criminal sentence—they
proceedings involve either a formal hearing before an
are transferred to DHS Immigration and Customs
immigration judge or a streamlined removal procedure (i.e.,
Enforcement (ICE) custody and placed in immigration
expedited removal) without hearings or significant review.
detention. ICE, which represents the government in
removal hearings, then commences removal proceedings.
Arriving foreign nationals who seek asylum (described
below) may request it at a U.S. port of entry before an
Because children are not permitted in DOJ criminal
admissions officer with the DHS Customs and Border
detention with adults, prosecuting adults who cross the
Protection (CBP) Office of Field Operations, or upon
border illegally with their children poses unique challenges.
apprehension between U.S. ports of entry before an agent
Once DHS transfers an adult to DOJ custody, it generally
with CBP’s U.S. Border Patrol. All aliens requesting
treats accompanying minor children as unaccompanied
asylum are entitled to an interview with an asylum officer
alien children (UAC) and transfers them to the care and
to assess the credibility of their asylum claims.
custody of the Department of Health and Human Services
(HHS) Office of Refugee Resettlement (ORR) (see below).
Illegal U.S. Entry
However, a California federal court ruled that if DHS
separates families to enable the prosecution of adult illegal
Aliens entering the United States illegally face two types of
entrants, DHS is required to reunite the families after
penalties. First, the Immigration and Nationality Act (INA)
criminal proceedings conclude and any sentence is served.
establishes civil penalties for persons who are in the United
States unlawfully (i.e., without legal status). These penalties
Unaccompanied Children
apply to aliens who entered the United States illegally as
well as those who entered legally but subsequently violated
Federal law contains distinct provisions for unaccompanied
the terms of their admission, typically by “overstaying”
alien children, defined as (1) lacking lawful immigration
their visa duration. Foreign nationals apprehended for such
status in the United States, (2) under age 18, and (3)
civil immigration violations are generally subject to
without a parent or legal guardian in the United States or
removal (deportation) and placed in removal proceedings.
one available to provide care and physical custody.
Second, the INA establishes criminal penalties for (1)
UACs are not subject to expedited removal. Instead, a UAC
persons who are convicted of entering or attempting to
who immigration authorities determine to be subject to
enter the United States illegally between ports of entry, (2)
removal is generally placed in formal removal proceedings.
eluding examination or inspection by immigration officers,
DHS may permit a UAC to voluntarily return to his or her
or (3) attempting to enter or obtaining entry to the United
country in lieu of removal proceedings, but only if the UAC
States through fraud or willful misrepresentation (generally
is a national or habitual resident of a contiguous country
classified as a misdemeanor). In addition, the INA provides
(i.e., Mexico and Canada), and (1) has not been, or is not at
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U.S. Immigration Laws for Aliens Arriving at the Border
risk in his or her country of being, a victim of human
Credible fear means that there is “a significant possibility,”
trafficking; (2) does not have a credible fear of persecution
taking into account the credibility of the statements made
in his or her country; and (3) is capable of independently
by the alien in support of his or her claim and such other
withdrawing his or her application for U.S. admission. A
facts as are known to the officer, that the alien could
UAC from Mexico or Canada must be screened within 48
establish eligibility for asylum. Those who receive a
hours of apprehension to determine whether he or she can
favorable credible fear determination are placed into formal
voluntarily return.
removal proceedings and given a hearing before an
immigration judge, thereby placing an asylum seeker on the
If a UAC is not from a contiguous country or is from a
defensive path to asylum. Those who receive an
contiguous country but has a credible fear of persecution, or
unfavorable credible fear determination may request that an
CBP does not make a determination within the 48-hour
immigration judge review the case. Aliens in expedited
screening period, the UAC is to be placed in the custody of
removal who cannot demonstrate a credible fear are
ORR pending formal removal proceedings.
promptly deported.
A child typically must be transferred to ORR within 72
Removal
hours after DHS determines he or she is a UAC. ORR must
Under the formal removal process, an immigration judge
then place the UAC “in the least restrictive setting that is in
from DOJ’s Executive Office for Immigration Review
the best interest of the child.” UACs are typically released
(EOIR) determines whether an alien is removable. The
to sponsors, most of whom are parents or close relatives
immigration judge may grant certain forms of relief (e.g.,
already residing in the United States. In 2018, UACs spent
asylum, cancellation of removal), and removal decisions are
an average of 60 days in ORR custody.
subject to administrative and judicial review.
Family Units
Under streamlined removal procedures, which include
Although UACs are not subject to expedited removal,
expedited removal and reinstatement of removal (i.e., when
accompanied alien children, such as those arriving at the
DHS reinstates a removal order for a previously removed
border with family members, are generally treated the same
alien), opportunities for relief and review are generally
as non-citizen adults, and may face either expedited or
limited. Under expedited removal, an alien who lacks
formal removal proceedings with the family unit.
proper documentation or has committed fraud or willful
Generally, DHS detains children and accompanying parents
misrepresentation to gain admission into the United States
in family residential centers for limited periods (typically
may be removed without any further hearings or review,
not exceeding 20 days) before releasing them pending their
unless he or she indicates a fear of persecution in the home
removal proceedings.
country or an intention to apply for asylum. Two other
removal options, often referred to as “returns”—voluntary
Asylum
departure and withdrawal of petition for admission—
require aliens to leave the United States promptly but
Many aliens arriving at the Southern border seek asylum in
exempt them from certain penalties associated with other
the United States. Asylum is a protection granted to foreign
types of removal.
nationals physically present within the United States or at
the U.S. border who meet the definition of a refugee. The
Expedited removal can be applied to any alien who meets
INA defines refugee as a person who is outside his or her
the expedited removal inadmissibility criteria described
home country (a second country that is not the United
above, has not been admitted or paroled (i.e., given
States) and is unable or unwilling to return because of
temporary permission to enter or remain in the United
persecution, or a well-founded fear of persecution, on one
States despite being inadmissible), and cannot affirmatively
or more of five possible criteria: (1) race, (2) religion, (3)
show continuous physical presence for the prior two years.
nationality, (4) membership in a particular social group, or
As a matter of policy, however, expedited removal to date
(5) political opinion. Asylum is not numerically limited and
has been limited to persons apprehended within 100 miles
is granted on a case-by-case basis. Asylum can be requested
of the U.S. border and who have been present in the United
by foreign nationals who have legally entered the United
States and are not in removal proceedings (“affirmative”
States for less than 14 days. Executive Order 13767, issued
on January 25, 2017, mandates that DHS expand expedited
asylum, not discussed below) or those who are in removal
removal to the full extent of the statute. That expansion has
proceedings and claim asylum as a defense to being
removed (“defensive” asylum).
not yet occurred.

If apprehended foreign nationals are found to be removable,
Arriving aliens who are inadmissible, either because they
ICE and CBP share the responsibility for repatriating
lack proper entry documents or because they attempt U.S.
them. CBP handles removals at the border for unauthorized
entry through misrepresentation or false claims to U.S.
aliens from Mexico and Canada, and ICE handles all
citizenship, are put into expedited removal. Aliens in
removals from the U.S. interior and removals for all
expedited removal who express a fear of persecution are to
unauthorized aliens from noncontiguous countries.
be detained by ICE and given a credible fear interview with
an asylum officer from DHS’s U.S. Citizenship and
Immigration Services (USCIS) to determine if the asylum
William A. Kandel, Analyst in Immigration Policy
claim has sufficient validity to merit a hearing before an
Hillel R. Smith, Legislative Attorney
immigration judge.
IF11074
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U.S. Immigration Laws for Aliens Arriving at the Border


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