Legal Sidebari

Immigration Laws Regulating the Admission
and Exclusion of Aliens at the Border
Updated July 21, 2020
Before the Coronavirus Disease 2019 (COVID-19) pandemic, the past few years had seen a marked
increase in the number of apprehensions of non-U.S. nationals (aliens) at the border seeking to unlawfully
enter the country. But entry restrictions at the U.S.-Mexico border in response to the COVID-19 pandemic
have significantly reduced the number of alien apprehensions. Border closures and emergency measures
in other countries have also restricted the ability of some “migrant caravans” to reach the United States.
Even so, there continues to be considerable attention concerning the treatment of aliens without legal
immigration status who arrive at or near the U.S.-Mexico border.
This Legal Sidebar briefly examines the laws generally governing the admission and exclusion of aliens
at the border, including the procedures for asylum seekers and the circumstances in which arriving aliens
may be detained. The Sidebar also addresses special rules for the treatment of unaccompanied alien
children (UACs), recent policy changes affecting the processing of aliens at the border, and legislative
proposals that would alter the scope of protections for arriving aliens. Table 1 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 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 the Department of Justice’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 or her own expense, potentially apply for relief from removal (such as asylum), present
testimony and evidence, 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. DHS may (but is not required to)
detain an alien during the pendency of formal removal proceedings, but may release the alien on bond or
Congressional Research Service
https://crsreports.congress.gov
LSB10150
CRS Legal Sidebar
Prepared for Members and
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the alien’s own recognizance. 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 further hearing or review if the alien lacks valid
entry documents or has attempted to procure admission by fraud or misrepresentation. (Aliens found
inadmissible on most other grounds, including because of criminal activity, are not subject to expedited
removal and instead are 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 (i.e., unlawful
entrants), 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 U.S. border within 14 days of entering the
country, and who have not been admitted or paroled.
In 2019, DHS exercised authority to employ expedited removal to the full degree authorized by INA
§235(b)(1), to include all aliens physically present in the United States without being admitted or paroled,
who have been in the country less than two years, when those aliens lack valid entry documents or
procured admission through fraud or misrepresentation. A federal district court initially enjoined DHS
from implementing this initiative pending the outcome of a lawsuit challenging that expansion, but the
U.S. Court of Appeals for the D.C. Circuit overturned that decision, enabling DHS to apply expedited
removal in the interior of the United States pending the outcome of the litigation.
An alien in expedited removal has limited procedural protections. Unlike in formal removal proceedings,
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 a determination as to whether
the alien should be subject to expedited removal. DHS, however, has the discretion to parole an alien
undergoing expedited removal in limited circumstances (e.g., because of a medical emergency), allowing
the alien to temporarily enter the United States pending a determination on whether the alien will be
admitted. As an alternative to expedited removal, DHS may permit the alien to voluntarily return to his or
her country if the alien 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

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the alien has shown a credible fear does not mean the alien will be granted relief from removal. Instead,
the alien 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 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” during
the pendency of 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 review of
DHS’s custody decision at a bond hearing and potentially be released from custody during the pendency
of those proceedings. In 2019 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.” But a federal district court held that this mandatory detention scheme
unconstitutionally denies aliens who have entered the United States the opportunity to seek release on
bond. The U.S. Court of Appeals for the Ninth Circuit has affirmed that decision. As a result, unlawful
entrants transferred to formal removal proceedings for consideration of asylum applications may not be
indefinitely detained by immigration authorities without a bond hearing.
If an alien does not establish a credible fear of persecution, the alien may still seek administrative review
of the asylum officer’s determination before an IJ (if the alien declines further review, the 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. Unless DHS grants parole, the alien will remain detained
pending the IJ’s determination. If the IJ concurs with the asylum officer’s finding, the alien will remain
subject to expedited removal; but if the IJ finds that the alien has a credible fear, the alien will be placed
in formal removal proceedings, and may pursue 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 when a person 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 claim before issuing an expedited removal order. If the immigration
officer cannot verify the claim, the claimant may still obtain administrative review before an IJ. The
claimant will be detained pending consideration of the claim unless DHS grants parole.
Special Rules Concerning the Treatment and Removal of UACs
Federal law sets forth different rules for the treatment of UACs, defined by statute to include those under
18 without 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, and are generally placed in formal removal proceedings
under INA §240, regardless of whether found in the United States or at the border. DHS may permit a
UAC to voluntarily return to his or her country in lieu of removal proceedings if the UAC is “a national or
habitual resident of a country that is contiguous with the United States” (i.e., Mexico or Canada), and the
child (1) has not been a victim of human trafficking (or is not at risk of human trafficking upon return to
the child’s native country); (2) does not have a credible fear of persecution in his or her country; and (3) is
capable of independently withdrawing his or her application for admission to the United States.

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A UAC believed to be from Mexico or Canada is required to be screened within 48 hours of apprehension
to determine whether he or she meets the criteria for voluntary return. If the UAC does not meet the
criteria (e.g., the UAC is from a noncontiguous country or, even though the UAC is from a contiguous
country, he or she 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 60 days.
Federal law also confers additional protections for UACs who apply for asylum that are generally
unavailable to other aliens. The one-year time limitation for most asylum applications does not apply to
UACs. A UAC also may apply for asylum even if he or she may be removed, pursuant to a safe third
country agreement, to a different country where he or she 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 applications filed by UACs. 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 the application before the IJ in formal removal proceedings).
Accompanied Alien Children
While UACs are not subject to expedited removal, accompanied alien children arriving with family
members may be subject to expedited or formal removal proceedings. Generally, DHS detains children
and accompanying parents in family residential facilities for limited periods (typically not exceeding 20
days due to a court settlement agreement) before releasing them for the pendency of removal proceedings.
In 2018, DOJ started a “zero tolerance” policy to criminally prosecute aliens who unlawfully enter the
United States at the southern border, resulting in the separation of children from parents subject to
prosecution (following the parents’ transfer to criminal custody by DOJ, the children were treated by DHS
as UACs and transferred to ORR custody). A federal court issued a preliminary injunction barring DHS
from detaining parents without their minor children at the border, unless the parents are unfit or present a
danger to the child, or have a criminal history or communicable disease. The court also ordered DHS to
reunite separated families. Following the injunction, DHS stopped referring parents for unlawful entry
prosecution if they had entered the United States as part of a family unit. The agency also allowed the
separation of parents from children only if the parent has a criminal history, presents a danger to the child,
has a communicable disease, or presents a fraudulent claim of parental relationship. The government,
which has made efforts to reunite families that have been separated, is not appealing the injunction.
Recent Policy Changes Affecting the Processing of Aliens at the Border
Since 2019, the Trump Administration has implemented new policies affecting the processing of aliens
arriving at the southern border who would normally be subject to expedited removal (e.g., because they
lack valid entry documents). These policies, discussed in more detail in other CRS products, include the
following:
1. The Migrant Protection Protocols (MPP) (or “Remain in Mexico” policy). Under this
2019 policy, some aliens arriving at the southern border are placed in formal removal

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proceedings rather than expedited removal, and returned to Mexico pending the outcome
of those proceedings. The MPP does not apply to Mexican nationals, UACs, or those who
show that it is more likely than not they will face persecution or torture in Mexico.
2. The third-country transit asylum bar. In 2019, DHS and DOJ jointly promulgated a
rule that makes aliens arriving at the southern border ineligible for asylum if they traveled
through another country without first seeking protection in that country. Such aliens will
be found not to have a credible fear of persecution, but may pursue withholding of
removal and CAT protection in formal removal proceedings if they show a “reasonable
fear” of persecution or torture. The rule potentially applies to UACs, who are placed in
formal removal proceedings rather than expedited removal. The rule is currently enjoined
from implementation by a federal district court.
3. Safe third country agreements (STCAs). In 2019, DHS signed STCAs with Guatemala,
Honduras, and El Salvador to enable the transfer of asylum seekers arriving at the U.S.
southern border to those countries. So far only the Guatemalan STCA has been
implemented, and only Honduran and El Salvadoran nationals have been subject to it.
Under the STCA, aliens screened for expedited removal who indicate an intention to
apply for asylum or a fear of persecution are sent to the receiving country (e.g.,
Guatemala) to pursue relief. But if the alien shows that he or she is more likely than not
to face persecution in the receiving country, the STCA does not apply and DHS will
proceed with the expedited removal process. The STCA does not apply to UACs.
4. Border entry restrictions. Responding to the COVID-19 pandemic, DHS limited
nonessential travel at land ports of entry at the northern and southern borders. These
measures were supplemented by an order from the Centers for Disease Control and
Prevention, barring entry for most aliens arriving from Canada or Mexico and requiring
their immediate return to the countries they entered from (or their country of origin).
DHS has temporarily suspended the inspection and processing of aliens arriving at the
border in most cases. Reportedly, UACs have also been subject to these entry restrictions.
Recent Legislative Activity
Proposals in the 116th Congress would alter procedures for arriving aliens at the border, though none
have been enacted. Some address the expedited removal process for arriving aliens, including review of
asylum claims raised by such persons. For example, some bills (H.R. 517, H.R. 3360) would heighten the
credible fear standard, while others (H.R. 3775, H.R. 3918, H.R. 4202) would clarify which immigration
officers may serve as “asylum officers.” Some bills would address the detention of aliens placed in
expedited removal, either by barring prolonged detention (S. 1243, H.R. 2415, H.R. 3918); or, conversely,
allowing indefinite detention and limiting the availability of parole (S. 1303, S. 1494, H.R. 586, H.R.
2522, H.R. 3360). Proposed legislation would also modify current law governing UACs. Some bills (H.R.
586, H.R. 2522, H.R. 3940, S. 1303, S. 1494) would allow any UAC to qualify for voluntary return in lieu
of removal proceedings, even if the UAC is not from a contiguous country; or require the placement of
UACs in expedited removal if they engaged in certain criminal activity (S. 1303, H.R. 2522). In addition,
some bills would remove DHS’s ability to return arriving aliens to Mexico or Canada pending the
outcome of formal removal proceedings (H.R. 5207), or require an alien’s “affirmative consent” before
being returned under that process (H.R. 3775). One bill (H.R. 3918) would prohibit the separation of an
alien minor from a parent or legal guardian near the border except in certain circumstances.

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Table 1. Procedures for Exclusion and Removal of Aliens
Voluntary
Departure/
Procedural
Voluntary
Removal
Rights and
Detention
Credible Fear
Return in Lieu
Category
Process
Protections
and Custody
and Asylum
of Removal
Alien within the
Generally placed
Aliens in formal
DHS may detain Alien may apply
Alien may apply
interior of the
in formal removal
removal have a
alien during the
for asylum and
for voluntary
United States
proceedings under
right to counsel,
pendency of
other protections
departure under
INA §240 (unless
to a hearing, to
proceedings, or
during formal
INA §240B prior
the alien meets
present evidence
release the alien removal
to or upon
the statutory
and apply for relief on bond or
proceedings; no
completion of
criteria to be
from removal, to
conditional
credible fear
proceedings if
placed in a
appeal adverse
parole. Aliens
assessment is
statutorily eligible.
different type of
decision to BIA,
removable for
required before
removal
and (as authorized
certain criminal
applying for
proceeding).
by statute) to seek or terrorist
asylum.

judicial review.
activity generally
must be
detained.
(1) Arriving
Generally placed
Generally no right
An alien is
In expedited
DHS may permit
alien
in expedited
to counsel,
normally
removal
an alien to
(2) Alien found
removal under
hearing, or further
detained during
proceedings, a
voluntarily return
in any part of
INA §235(b)(1) if
review in
expedited
credible fear
to his or her
the United
alien lacks valid
expedited
removal,
determination is
country in lieu of
States who has
entry documents
removal. Judicial
including while
required if an alien expedited removal
not been
or has attempted
review of
awaiting a
expresses an
if he intends, and
admitted or
to procure
expedited removal credible fear
intent to apply for
is able, to depart
paroled, and
admission through
order is available
determination,
asylum or a fear of the United States
who has been in fraud/
only in limited
but DHS may
persecution. If the
immediately.
the country less
misrepresentation
circumstances.
parole the alien
alien shows a
than two years
(if inadmissible on
But greater
for “urgent
credible fear,
other grounds,
humanitarian
asylum and related

procedural
alien is subject to
protections are
reasons” or
protections may
formal removal
afforded if an alien
“significant
be pursued in
proceedings under
otherwise subject
public benefit.”
formal removal
INA §240).
to expedited
If an alien
proceedings under
DHS may opt to
removal is placed
screened for
INA §240; if a
return aliens
in formal removal
expedited
credible fear claim
encountered at or
proceedings under
removal is
is rejected by the
near the U.S.-
the MPP.
placed in formal
asylum officer, the
Mexico border to
removal
alien may stil seek
Mexico pending
proceedings,
review from an IJ.
formal removal
detention is
Note: Safe third
proceedings under
mandatory
country
the MPP instead of
unless parole is
agreements and
expedited
granted. The
third-country
removal.
alien general y
transit bar may
may not be
preclude
released on
consideration of
bond. (An
many asylum
injunction now
claims.
requires bond

hearings for
unlawful
entrants initially
screened for
expedited

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Voluntary
Departure/
Procedural
Voluntary
Removal
Rights and
Detention
Credible Fear
Return in Lieu
Category
Process
Protections
and Custody
and Asylum
of Removal
removal but
then placed in
formal removal
proceedings.)
Unaccompanied
UACs may only be Aliens in formal
UACs are
UACs are not
A UAC may be
Alien Children
placed in removal
removal have a
placed in the
categorically
permitted to
proceedings under
right to counsel,
custody of ORR
exempted from
voluntarily return
INA §240,
to a hearing, to
during pendency the third-country
to his or her
regardless of
present evidence
of removal
transit asylum bar.
country in lieu of
whether they are
and apply for relief proceedings.
Non-disqualified
formal removal
found in the
from removal, to
ORR may place
UACs may apply
proceedings if
interior or arriving appeal adverse
a UAC with a
for asylum during
UAC is “a national
at the U.S. border.
decision to BIA,
sponsor who “is removal
or habitual
(UACs are not
and (as authorized
capable of
proceedings
resident” of
subject to the
by statute) to seek providing for
without an initial
Mexico or Canada,
MPP.)
judicial review.
the child’s
credible fear
and the alien (1)
physical and
assessment.
lacks a credible
mental well-
UACs are not
fear of
being.”
subject to one-
persecution; (2) is
year limitation for
not a victim or
seeking asylum,
likely victim of
and may pursue
trafficking; and (3)
asylum even if they is capable of
may safely be
agreeing to return.
removed to a
third country.
USCIS has initial
jurisdiction over
UACs’ asylum
applications even
in removal
proceedings. But a
UAC may stil
pursue application
before an IJ during
removal
proceedings.


Author Information

Hillel R. Smith

Legislative Attorney

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Disclaimer
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information that has been provided by CRS to Members of Congress in connection with CRS’s institutional role.
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LSB10150 · VERSION 15 · UPDATED

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