Legal Sidebari

An Overview of U.S. Immigration Laws
Regulating the Admission and Exclusion of
Aliens at the Border

Updated June 10, 2019
UPDATE: Following the publication of this Sidebar, there have been several developments concerning
the Trump Administration’s “zero tolerance” policy and the separation of families pending removal
proceedings or any unlawful entry criminal prosecution of a family member. A Legal Sidebar and CRS
Report addressing these developments and the legal issues they raise are available
here.
In addition, at the end of 2018, the Trump Administration announced new policies that would make aliens
who unlawfully enter the United States at the southern border ineligible for asylum, and that would
require many asylum seekers who arrive at the southern border to wait in Mexico pending the outcome of
their removal proceedings. Legal Sidebars addressing these policies and the court litigation concerning
the legality of these policies are available
here. The original post from June 15, 2018, as updated, is
below
.
Reports of a “migrant caravan” traveling from Central America to the United States have sparked
considerable attention on the treatment of non-U.S. nationals (aliens) without legal immigration status
who are arrested at or near the U.S.-Mexico border. The “caravan” comprises aliens primarily from
Honduras, many of whom purportedly came to the United States to escape crime and political instability
in their native countries. In recent months, there has been a marked increase in the number of
apprehensions
of aliens at the border seeking to unlawfully enter the country, with roughly three times as
many border apprehensions in May 2018 compared to the same time last year.
In response to this influx of unauthorized border crossings, President Trump and other administration
officials have called for stricter immigration laws and enhanced border security. In addition, the
Department of Justice (DOJ) has announced a “zero tolerance” policy to criminally prosecute aliens who
unlawfully enter
the United States at the southern border; a policy which has reportedly led to the
separation of children from parents awaiting prosecution for unlawful entry. The Administration and its
supporters argue that these policies serve as a “tough deterrent” that is necessary to curb illegal border
crossings. Opponents of these policies claim that U.S. immigration laws offer inadequate protections for
those seeking a “safe haven” in the United States, and some have also legally challenged the separation of
families on constitutional grounds.
Congressional Research Service
https://crsreports.congress.gov
LSB10150
CRS INSIGHT
Prepared for Members and
Committees of Congress




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The situation at the border and U.S. immigration authorities’ response to it has prompted significant
attention and, in some cases, confusion regarding the governing laws and policies. This Legal Sidebar
briefly examines the laws governing the admission and exclusion of aliens at the border, including the
procedures for aliens seeking asylum and the circumstances in which arriving aliens may be detained. The
Sidebar also addresses special rules concerning the treatment of unaccompanied alien children (UACs), as
well as legislative proposals that would alter the scope of protections for arriving aliens at the border. A
concluding Table provides an overview of the existing laws governing the detention and removal process
for aliens.
General Statutory Framework Governing the Removal of Aliens
The Immigration and Nationality Act (INA) establishes a number of avenues by which various categories
of aliens can be denied entry or removed from the United States. Typically, when the Department of
Homeland Security (DHS) seeks to remove an alien found in the interior of the United States, it institutes
removal proceedings
under INA § 240. These “formal” proceedings are conducted by an immigration
judge
(IJ) within DOJ’s Executive Office for Immigration Review. Aliens are afforded a number of
procedural protections in such proceedings. For example, the alien may be represented by counsel at his
own expense, potentially apply for relief from removal (such as asylum), present testimony and evidence
on his own behalf, and appeal an adverse decision to the Board of Immigration Appeals (BIA), the highest
administrative body responsible for interpreting and applying U.S. immigration laws. Additionally, the
alien may, as authorized by statute, seek judicial review of a final order of removal in the judicial circuit
in which the removal proceedings were completed. Generally, DHS may (but is not required to) detain an
alien while formal removal proceedings
are pending, and may release the alien on bond or grant
conditional parole as a matter of discretion (however, detention is mandatory if the alien is removable on
certain criminal or terrorist-related grounds except in limited circumstances).
Expedited Removal
The INA sets forth a separate removal process for certain arriving aliens who have not been admitted into
the United States; a process that significantly differs from the formal removal proceedings governed by
INA § 240. Specifically, INA § 235(b)(1) provides that an alien arriving at the U.S. border or a port of
entry may be removed from the United States without a hearing or further review if he lacks valid entry
documents or has attempted to procure his admission by fraud or misrepresentation. (Aliens found
inadmissible on most other grounds—e.g., because of certain criminal activity—are not subject to
expedited removal and will instead be placed in formal removal proceedings.) The expedited removal
statute also authorizes – but does not require – DHS to apply this process to aliens inadmissible on the
same grounds who have not been admitted or paroled into the United States by immigration authorities,
and who have been physically present in the United States for less than two years. Based on this authority,
DHS has implemented expedited removal with respect to the following categories of aliens:
1. arriving aliens seeking entry into the United States;
2. aliens who entered the United States by sea without being admitted or paroled, and who
have been in the country less than two years; and
3. aliens apprehended within 100 miles of the United States border within 14 days of
entering the country, and who have not been admitted or paroled.
Unlike in formal removal proceedings, an alien subject to expedited removal has limited procedural
protections.
The alien has no right to counsel during the expedited removal process, no right to a hearing,
and no right to appeal an adverse ruling to the BIA. Judicial review of an expedited removal order also is
limited in scope.
Further, the INA provides that an alien “shall be detained” pending expedited removal
proceedings. DHS, however, has the discretion to parole an alien undergoing expedited removal for


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“urgent humanitarian reasons” or “significant public benefit,” thereby allowing the alien to temporarily
enter
the United States pending a determination as to whether he should be admitted. In addition, as an
alternative to expedited removal, the agency may permit the alien to voluntarily return to his country if he
intends, and is able, to depart the United States immediately.
Aliens Seeking Asylum
Although an alien subject to expedited removal typically has no right to administrative review, there is an
exception
if the alien expresses either an intent to apply for asylum or a more generalized fear of
persecution if removed to a particular country. In these circumstances, the alien must be referred to an
asylum officer within DHS’s U.S. Citizenship and Immigration Services (USCIS) to determine whether
the alien has a credible fear of persecution (but this exception does not apply to certain aliens arriving
from Canada
who could seek protection in that country). Under this “low screening standard,” the alien
has to show a “substantial and realistic possibility of success on the merits” of an application for asylum,
withholding of removal, or protection under the Convention Against Torture (CAT). A determination that
the alien has demonstrated a credible fear does not mean that the alien will be granted relief from
removal. Instead, if the alien shows a credible fear of persecution or torture, he will be placed in formal
removal proceedings under INA § 240 in lieu of expedited removal, and may pursue an application for
asylum and related protections in those proceedings. To be granted such relief, the alien will have to
satisfy a higher threshold of proof of eligibility for relief than was required to satisfy the initial credible
fear screening (e.g., a “well-founded” fear of persecution to qualify for asylum, or that it is “more likely
than” not that the alien would face torture to obtain CAT protection).
The INA provides that an alien who establishes a credible fear of persecution “shall be detained” pending
the formal removal proceedings, but authorizes DHS to grant parole as a matter of discretion. For many
years, immigration authorities had construed the statute and regulations to provide that, when an alien
apprehended between ports of entry and initially screened for expedited removal was placed in formal
removal proceedings following a credible fear determination, that alien could seek bond and potentially
be released from custody during the pendency of those proceedings. In April 2019, however, Attorney
General William Barr reversed this position, ruling instead that aliens subject to expedited removal who
are placed in formal removal proceedings after a positive credible fear determination may not be released
on bond, “whether they are arriving at the border or are apprehended in the United States.” (The Attorney
General’s ruling has been challenged in federal district court and that case remains pending.)
If an alien does not establish a credible fear of persecution, he may still seek administrative review of the
asylum officer’s determination before an IJ (if the alien declines further review, the USCIS asylum officer
will issue an order of removal). The IJ’s review must be conducted “within 24 hours, but in no case later
than 7 days” after the asylum officer’s decision, and the alien will remain detained pending the IJ’s
determination unless DHS grants parole. If the IJ concurs with the asylum officer’s finding, the alien will
remain subject to expedited removal;
on the other hand, if the IJ determines that the alien has a credible
fear, the alien will be placed in formal removal proceedings under INA § 240, and he may pursue an
application for asylum and related protections in those proceedings.
Aliens Who Claim to be U.S. Citizens, Lawful Permanent Residents, Admitted
Refugees, or Persons Who Have Been Granted Asylum

The INA also provides for an exception to expedited removal in cases where an alien claims to be a U.S.
citizen, a lawful permanent resident (LPR), an admitted refugee, or a person granted asylum. The
immigration officer must attempt to verify the alien’s claim before issuing an expedited removal order.
Further, even if the immigration officer cannot verify the alien’s claim, the alien may still obtain


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administrative review of his claim before an IJ. The alien will be detained pending consideration of his
claim unless DHS grants parole.
Special Rules Concerning the Treatment and Removal of UACs
Federal law notably sets forth different rules and procedures governing the treatment of UACs, who are
defined by statute to include children under the age of 18 with no lawful immigration status who either (1)
have no parent or legal guardian in the United States, or (2) have no parent or legal guardian in the United
States available to provide care and physical custody.
UACs are not subject to expedited removal. Instead, a UAC who is determined by immigration authorities
to be subject to removal is generally placed in formal removal proceedings under INA § 240, regardless of
whether the alien is found in the interior of the United States or at the border. In limited circumstances,
DHS may permit a UAC to voluntarily return to his country in lieu of removal proceedings, but only if
the UAC is “a national or habitual resident of a country that is contiguous with the United States” (i.e.,
Mexico and Canada), and the child (1) has not been a victim of human trafficking (or is not at risk of
human trafficking upon return to his native country); (2) does not have a credible fear of persecution in
his country; and (3) is capable of independently withdrawing his application for admission to the United
States.
A UAC who is believed to be from Mexico or Canada is required to be screened within 48 hours of his
apprehension to determine whether he meets the criteria for voluntary return. If the UAC does not meet
the criteria (e.g., the UAC is from a non-contiguous country or, even though he is from a contiguous
country, he has a credible fear of persecution), or no determination is made within the 48-hour screening
period, the UAC will be placed in the custody of the Department of Health and Human Services’ Office of
Refugee Resettlement (ORR)
pending formal removal proceedings under INA § 240. The UAC typically
must be transferred to ORR within 72 hours after DHS determines that the child is a UAC. Following
transfer to ORR, the agency generally must place the UAC “in the least restrictive setting that is in the
best interest of the child.” In assessing the appropriate setting, ORR may consider the child’s “danger to
self, danger to the community, and risk of flight,” and it may place the child with a sponsoring individual
or entity after determining that the sponsor “is capable of providing for the child’s physical and mental
well-being.” In practice, executive officials have told Congress that the majority of UACs are released to
individual sponsors, most of whom are parents or close relatives, within sixty days.
Federal laws also confer additional protections for UACs who apply for asylum which are generally
unavailable to other categories of aliens. The one-year time limitation for most asylum applications does
not apply to UACs seeking asylum. A UAC also may apply for asylum even if he may be removed,
pursuant to a bilateral or multilateral agreement, to a country (other than his native country) where he
would not face persecution and could seek asylum-related protections. Further, while aliens seeking
asylum generally apply either “affirmatively” with USCIS or “defensively” in removal proceedings
before an IJ, USCIS asylum officers have initial jurisdiction over any asylum application filed by a UAC.
A USCIS asylum officer has initial jurisdiction even if the UAC is in removal proceedings (though if the
asylum officer determines that the UAC is not eligible for asylum, the UAC may still pursue his
application before the IJ in removal proceedings).
Accompanied Alien Children
Although UACs may not be removed via expedited removal, accompanied alien children (such as those
arriving in the United States with family members) are generally treated in the same manner as non-
citizen adults, and may be subject to either expedited or formal removal proceedings. Generally, DHS has
detained children and their accompanying parents in family residential centers for limited periods
(typically not exceeding 20 days) before releasing them pending their removal proceedings.


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Recently, however, DOJ implemented a "zero tolerance" policy to criminally prosecute aliens who
unlawfully enter the United States at the southern border, which reportedly has resulted in the separation
of children from parents who are subject to prosecution. In these cases, the parents are transferred from
the custody of immigration authorities in DHS to criminal custody by DOJ, while the children remain in
immigration custody. While the parents are placed in pre-trial detention pending their unlawful entry
prosecution, their children are treated by DHS as UACs and transferred to the custody of ORR. The
children are reportedly treated by DHS as UACs because they cannot be detained with their parents in
criminal custody, and therefore the children are deemed not to have a parent available to provide “care
and physical custody.” A
ccording to DHS, however, the agency itself does not have a policy of
automatically separating families at the border and placing them in different immigration detention
spaces, but there may be circumstances where family separation occurs (e.g., when separating children
from accompanying adults while determining their family relationship, or when the parents are believed
to have engaged in criminal conduct and are transferred to federal criminal law enforcement authorities).
While the INA’s statutory scheme does not prohibit the separation of families detained for immigration
enforcement purposes, plaintiffs in California have filed a class action lawsuit arguing that this practice
violates due process protections of separated persons. Recently, a federal district court in California
refused to dismiss the lawsuit and rejected the government’s contention that the families have no
constitutional right to remain together. The district court’s ultimate ruling in the case may significantly
impact the government’s policies with respect to families and accompanied children at the border.
Recent Legislative Activity
In recent years, there have been several legislative proposals that would alter the procedures for arriving
aliens at the border, generally by restricting their rights and protections. Some of these proposals address
the expedited removal process for arriving aliens, including review of asylum claims raised by such
persons. For example, the Asylum Reform and Border Protection Act (H.R.391) and the Repeal Executive
Amnesty Act of 2015
(S.129) would impose for credible fear assessments an additional requirement that
“it is more probable than not that the statements made by the alien in support of the alien’s claim are
true.” The bills also would restrict DHS’s ability to grant humanitarian parole except in limited
circumstances (e.g., when the alien has a life-threatening medical emergency and is permitted to enter the
United States to receive medical care). Other recent legislation would have (1) expanded the scope of
expedited removal under INA § 235(b)(1) to cover arriving aliens who pose “threats to public safety”
based on certain criminal, gang-related, or terrorist activity, or previous immigration violations; (2)
restricted DHS’s ability to grant parole to aliens involved in gang activity; and (3) barred gang members
from most forms of discretionary relief, including asylum.
There is also proposed legislation that would modify current law governing UACs. For example, the
Protection of Children Act of 2017 (H.R.495) and the Protecting Children and America’s Homeland Act
of 2017
(PCAHA) (Title III, Subtitle B of S.1757) would allow any UAC to qualify for voluntary return
in lieu of removal proceedings, even if the UAC did not come from a contiguous country. The PCAHA
would also expand expedited removal under INA § 235(b)(1) to cover UACs who have previously entered
the United States unlawfully or engaged in certain criminal, terrorist, or gang-related activity. In addition,
H.R. 5163, introduced in 2014, would have created a new removal process that would require a threshold
assessment of whether a UAC is likely admissible to the United States or eligible for any form of relief
from removal (The PCAHA would create a similar procedure for UACs who meet the criteria for
voluntary return but choose not to return to their home country). These bills would also impose time
limitations for removal proceedings involving UACs and modify the procedures and requirements for the
detention and release of UACs.
Other bills would modify current law regarding UACs by amending the UAC definition to exclude
application to a child who has an adult sibling, aunt, uncle, grandparent, or adult cousin who may provide


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care and physical custody. Finally, with respect to accompanied children, there have been legislative
proposals
to prohibit the separation of alien children from their families. In short, lawmakers have
proposed various options in recent years to alter the scope of protections for UACs specifically and aliens
arriving in the United States generally, though to date no such measure has been enacted. Given recent
developments concerning “migrant caravans,” Congress may consider additional legislative initiatives in
the future.
Table: Overview of Laws Governing the Exclusion and Removal of Aliens
Voluntary
Departure/Volu
Procedural
ntary Return in
Removal
Rights and
Detention and
Credible Fear
Lieu of
Category
Process
Protections
Custody
and Asylum
Removal
Alien within the
Generally formal
Right to counsel,
DHS generally
May apply for
Alien may apply
interior of the
removal
right to a hearing,
may detain alien
asylum and
for voluntary
United States
proceedings
right to present
pending
related
departure under
under INA § 240
evidence and
proceedings, but
protections
INA § 240B prior
(unless the alien
apply for relief
may release alien
during removal
to or upon
meets the
from removal,
on bond or grant
proceedings; no
completion of
statutory criteria
right to appeal
conditional
credible fear
removal
to be placed in a
adverse decision
parole; detention
assessment
proceedings if
different type of
to BIA, and (as
is mandatory for
required before
certain statutory
removal
authorized by
aliens removable
applying for
requirements are
proceeding)
statute) right to
on certain
asylum
met

seek judicial
criminal/terrorist-
review
related grounds
except in limited
circumstances
(1) Arriving alien
Expedited
Generally no right Detention is
Credible fear
DHS may permit
(2) Alien who
removal
to counsel,
mandatory during
determination
alien to
entered the
proceedings
hearing, or
expedited
required if alien
voluntarily return
United States by
under INA §
further review.
removal process
expresses an
to his country in
sea without being
235(b)(1) if alien
Judicial review of
(including pending intent to apply for lieu of expedited
admitted or
lacks valid entry
expedited
credible fear
asylum or a fear
removal
paroled and who
documents or has removal order
determination)
of persecution; if
proceedings if he
has been in the
attempted to
available only in
but DHS may
alien shows a
intends, and is
country for less
procure
limited
parole alien for
credible fear, he
able, to depart
than two years
admission
circumstances
“urgent
may pursue
the United States
through
humanitarian
asylum and
immediately
(3) Alien
fraud/misrepresen
reasons” or
related
apprehended
tation (if
“significant public
protections in
within 100 miles
inadmissible on
benefit”
formal removal
of U.S. border
other grounds,
proceedings
within 14 days of
If alien is placed in
alien is subject to
under INA § 240;
entering the
formal removal
formal removal
if credible fear
country who has
proceedings (e.g.,
proceedings
claim is rejected
not been
because alien has
under INA § 240)
by the asylum
admitted or
a credible fear),
officer, the alien
paroled
detention is
mandatory
may stil seek
(unless DHS
administrative
grants parole) and review before IJ
alien may not be
released on bond
Unaccompanied
Formal removal
Right to counsel,
Alien is placed in
May apply for
Alien may be
Alien Children
proceedings
right to a hearing,
custody of ORR
asylum and
permitted to
under INA § 240
right to present
pending removal
related
voluntarily return


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Voluntary
Departure/Volu
Procedural
ntary Return in
Removal
Rights and
Detention and
Credible Fear
Lieu of
Category
Process
Protections
Custody
and Asylum
Removal
(regardless of
evidence and
proceedings;
protections
to his country in
whether alien is
apply for relief
ORR may place
during removal
lieu of formal
found in the
from removal,
alien with a
proceedings; no
removal
interior of the
right to appeal
sponsor who “is
credible fear
proceedings if he
U.S. or at the
adverse decision
capable of
assessment
is “a national or
border)
to BIA, and (as
providing for the
required.
habitual resident
authorized by
child’s physical
Alien is not
of a country that
statute) right to
and mental well-
subject to one-
is contiguous with
seek judicial
being”
year time
the United
review
limitation for
States” and alien
asylum
(1) lacks a
applications, and
credible fear of
may pursue
persecution; (2) is
asylum even if he
not a victim or
may be removed
likely victim of
to third country
trafficking; and (3)
where he could
is capable of
seek asylum-
agreeing to
related
return
protections under
the receiving
country’s laws;
USCIS has initial
jurisdiction over
any asylum
application even if
alien is in removal
proceedings; alien
may stil pursue
application before
IJ in removal
proceedings


Author Information

Hillel R. Smith

Legislative Attorney







Congressional Research Service
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