Legal Sidebari

Immigration Arrests in the Interior of the
United States: A Primer
Updated June 3, 2021
U.S. Immigration and Customs Enforcement (ICE), a component of the Department of Homeland
Security (DHS), is primarily responsible for immigration enforcement in the interior of the United States.
ICE has substantial authority to arrest and detain non-U.S. nationals (aliens) identified for removal
because of immigration violations. In recent years, there had been a marked increase in arrests and
removals conducted by ICE. As discussed in this Legal Sidebar and as compared to prior administrations,
the Trump Administration made enforcement a touchstone of its immigration policy, and ICE generally
sought to enforce federal immigration laws against a broader range of aliens who had committed
immigration violations. A recalibration of priorities by the Biden Administration has led ICE to prioritize
immigration enforcement actions pertaining to a narrower category of aliens; namely, those who present
terrorism or national security concerns, those who recently came to or attempted to unlawfully enter the
United States, or those who pose a threat to public safety based on the commission of certain crimes.
While immigration enforcement priorities may change over time, the governing authorities for ICE’s
activities have largely remained constant. This Legal Sidebar provides an overview of ICE’s authority to
conduct arrests and other enforcement actions.
ICE’s General Authority to Arrest and Detain
ICE was established following the creation of DHS in 2003. The agency’s stated mission is “to protect
America from the cross-border crime and illegal immigration that threaten national security and public
safety.” ICE officers’ authority to arrest aliens believed to have committed immigration violations derives
primarily from two federal statutes: Sections 236 and 287 of the Immigration and Nationality Act (INA).
INA § 236(a) provides that an immigration officer may arrest and detain an alien who is subject to
removal upon issuance of a “Warrant for Arrest of Alien.” This administrative arrest warrant (ICE
Warrant) may be issued with a Notice to Appear (NTA), the charging document that initiates formal
removal proceedings, or “at any time thereafter and up to the time removal proceedings are completed.”
DHS regulations provide that the ICE warrant may be issued only by certain designated immigration
officials (e.g., a supervisory officer). In addition, an ICE warrant is issued exclusively for use by
immigration officers. Reviewing courts have recognized that this administrative warrant may not serve as
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the basis for state or local law enforcement officials to arrest and detain an alien, except when done under
the terms of a cooperative agreement with federal authorities under INA § 287(g).
While an immigration-related arrest generally requires an ICE warrant, INA § 287(a)(2) lists two
circumstances when an ICE warrant is not required for an immigration officer to arrest an alien for a
suspected immigration violation:
1. the alien, in the presence or view of the immigration officer, is entering or attempting to
enter the United States unlawfully; or
2. the immigration officer has “reason to believe” that the alien is in the United States in
violation of law and is likely to escape before a warrant can be obtained.
The immigration officer must also have completed immigration law enforcement training and be one of
the designated immigration officers who have the warrantless arrest authority under DHS regulations.
While this Legal Sidebar focuses on ICE officers’ authority to arrest aliens for immigration violations that
render them removable, it bears mentioning that ICE frequently investigates and arrests persons who may
potentially be subject to both criminal prosecution and removal proceedings (e.g., transnational criminal
street gangs). INA § 287(a) permits designated immigration enforcement officers, during the course of
their immigration enforcement duties, to make warrantless arrests of aliens and other persons for criminal
offenses in specified circumstances (e.g., when the offense is committed in the officer’s presence, or the
officer has reason to believe the suspect committed a felony and would likely escape before a warrant
could be obtained). DHS regulations require the immigration officer to advise the person being arrested of
his or her legal rights, and to arrange promptly for that person’s initial appearance before a federal
magistrate or district court judge.
Limitations to ICE’s Arrest Authority for Civil Immigration Violations
Generally, upon issuance of an ICE warrant, or “reason to believe” that an alien is removable and likely to
escape, an authorized immigration officer may arrest and detain an alien. There are constitutional
restrictions on this arrest authority. The Fourth Amendment’s protections against unreasonable searches
and seizures apply to immigration-related arrests and detentions. Thus, reviewing courts have interpreted
the “reason to believe” standard for warrantless immigration arrests to be the equivalent of probable
cause. Under this standard, the immigration officer must have sufficient facts that would lead a reasonable
person to believe, based on the circumstances, that the alien has violated federal immigration laws and is
likely to escape before an ICE warrant can be obtained.
The Supreme Court also has held that the Fourth Amendment’s prohibition against unreasonable seizures
precludes the use of excessive force during an arrest. Thus, DHS regulations provide that “non-deadly
force” may be used only when the immigration officer reasonably believes that such force is warranted,
and that a “minimum” level of non-deadly force should be employed unless circumstances warrant a
greater degree of force. And the regulations instruct that “deadly force”—defined as “any use of force that
is likely to cause death or serious physical injury”—may be used only when the officer reasonably
believes that such force is necessary to protect the officer or others from death or serious harm. The
regulations also prohibit the use of threats or physical abuse to compel an individual to make a statement
or waive his or her legal rights.
The Supreme Court has also long held that the Fourth Amendment prohibits the government’s
nonconsensual entry into a person’s home without a judicial warrant. This restriction may also extend to
other areas where there is a reasonable expectation of privacy, such as the non-public part of a workplace
or business. Unlike judicial warrants, ICE warrants are purely administrative, as they are neither reviewed
nor issued by a judge or magistrate, and therefore do not confer the same authority as judicially approved
arrest warrants. Applying these principles, some courts have ruled that ICE agents violated the Fourth

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Amendment by forcibly entering homes without a judicial warrant, when no exigent circumstances or
other exceptions to general Fourth Amendment requirements existed. Thus, immigration authorities
would generally be unable to enter homes and non-public parts of a business absent exigent circumstances
(e.g., risk of harm to the public, potential destruction of evidence) or the owner’s consent.
ICE also has a long-standing policy of not taking enforcement actions (i.e., arrests, interviews, searches,
and surveillance) at certain “sensitive locations.” These sensitive locations currently include schools
(including postsecondary institutions); hospitals and other health care facilities; Coronavirus Disease
2019 (COVID-19) vaccination sites; places of worship; courthouses (including the close vicinity of a
courthouse); public demonstrations; and the sites of funerals, weddings, or other public religious
ceremonies. ICE officers may engage in an enforcement action at a sensitive location only with prior
approval from a supervisory official, unless (1) the enforcement action involves a national security or
terrorism matter; (2) there is an imminent risk of death, violence, or physical harm to any person; (3) the
enforcement action involves the hot pursuit of a person who presents a danger to public safety; or (4)
there is an imminent risk of destruction of evidence material to a criminal case. For courthouses, an
immigration enforcement action may be taken against a person who poses a threat to public safety only if
a safe alternative location for such action does not exist or would be too difficult to achieve, and the
action has been approved by a supervisory official.
Immigration-Related Arrest and Detention Process
DHS regulations provide that, upon an arrest (with or without an ICE warrant), the immigration officer
must promptly identify himself if it is practical and safe to do so, and inform the alien of the reason for
the arrest. If the arrested individual claims to be a U.S. citizen, ICE guidelines require the immigration
officer to assess any evidence of citizenship before taking that individual into custody. Before transporting
the alien to an ICE facility, the officer may search the alien “as thoroughly as circumstances permit.” The
alien must be transported “in a manner that ensures the safety of the persons being transported,” and the
alien “shall not be handcuffed to the frame or any part of the moving vehicle or an object in the moving
vehicle,” or left unattended during transport.
Typically, an alien arrested under an ICE warrant is taken into custody pending removal proceedings. At
any time during those proceedings, ICE may decide to release the alien (but in some cases, such as when
aliens have committed specified crimes, detention is mandatory). If an alien is arrested without an ICE
warrant, DHS regulations require the alien to first be “examined by an officer other than the arresting
officer,” unless no other qualified immigration officer is “readily available.” If the examining officer
determines there is sufficient evidence that the alien has committed an immigration violation, the alien is
to be issued an NTA and placed in removal proceedings. ICE must decide within 48 hours of a
warrantless arrest whether to issue an NTA and whether to keep the alien detained. In “an emergency or
other extraordinary circumstance,” the regulations permit ICE to exceed the 48-hour time limitation and
make its charging and custody determinations “within an additional reasonable period of time.”
If an alien is placed in formal removal proceedings and then issued a final order of removal, the alien is
generally subject to detention pending efforts to secure removal (though aliens usually must be released
from custody if removal is not effectuated within a certain period). If the alien is not in ICE’s physical
custody, the agency will typically issue a “Bag and Baggage” letter directing the alien to report to ICE so
removal may be effectuated. If the alien fails to surrender, ICE may arrest the alien under an
administrative Warrant of Removal. As noted above, an administrative warrant does not confer authority
to enter a home or private area. The immigration officer’s ability to arrest the alien may also be restricted
by ICE’s “sensitive locations” policy.

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Routine Questioning and Brief Investigative Detentions
ICE also has authority to conduct interrogations and brief detentions as part of an investigation into
possible immigration violations. INA § 287(a)(1) states that an immigration officer may, without a
warrant, “interrogate any alien or person believed to be an alien as to his right to be or to remain in the
United States.” The exercise of this authority is subject to constraint under the Fourth Amendment. The
Supreme Court has declared that law enforcement officers do not violate the Fourth Amendment by
merely questioning individuals in public places. Therefore, in INS v. Delgado, the Court held that
immigration officers did not violate the Fourth Amendment by entering factory buildings (which the
Court treated as “public places” because the officers had acted on either a warrant or the employer’s
consent) and questioning employees about their citizenship, even if there were armed officers stationed
near the exit doors. The Court reasoned that the questioning was “nothing more than a brief encounter”
that did not prevent the employees from going about their business.
The Supreme Court, however, has long held that certain, more intrusive encounters that do not rise to the
level of an arrest, such as a brief detention or “stop and frisk,” may be justified only if there is reasonable
suspicion that a crime is afoot. This standard, lower than the probable cause threshold for an arrest,
requires specific, articulable facts—rather than a mere hunch—that reasonably warrant suspicion of
unlawful activity. The Supreme Court has applied this standard to immigration-related detentions. For
example, in United States v. Brignoni-Ponce, the Court held that random automobile stops near the border
to question the occupants about their immigration status require reasonable suspicion that the occupants
are aliens who may be unlawfully present in the United States. (Conversely, in INS v. Delgado,
immigration authorities did not require any individualized suspicion to question factory employees
because they were not being detained.)
The Supreme Court has not decided, more generally, whether immigration authorities may briefly detain
individuals solely on a reasonable suspicion that they are aliens, absent reasonable suspicion of their
unlawful presence. Some lower courts, however, have ruled that an immigration officer may not detain an
alien to investigate his or her immigration status (e.g., stopping a pedestrian on the street) absent
reasonable suspicion of the alien’s unlawful presence. Some courts have held that the officer may not rely
solely on “generalizations,” such as an individual’s appearance, ethnicity, or inability to speak English, to
establish reasonable suspicion.
Reflecting some of these Fourth Amendment constraints, DHS regulations provide that an immigration
officer may question an individual so long as the officer “does not restrain the freedom of an individual,
not under arrest, to walk away.” An immigration officer may “briefly detain” an individual for
questioning only if there is reasonable suspicion that the person is “engaged in an offense against the
United States or is an alien illegally in the United States.” The information obtained from the immigration
officer’s questioning “may provide the basis for a subsequent arrest” (e.g., if the immigration officer
forms probable cause that the alien is unlawfully present in the United States).
Worksite Inspections
ICE also has statutory authority to conduct worksite inspections to enforce federal immigration laws on
the employment of aliens. Under INA § 274A, it is unlawful for “a person or other entity” knowingly to
employ an “unauthorized alien,” defined as an alien who is not lawfully admitted for permanent residence
or otherwise authorized to be employed in the United States. The statute requires an employer to complete
a Form I-9 attesting that a person hired for employment is not an unauthorized alien. The employer must
also retain the I-9 form for inspection for three years after the hiring. DHS regulations allow ICE to
conduct the inspection at the employer’s place of business with at least three business days’ notice. I-9
site inspections do not require an administrative or judicial warrant, or probable cause of an immigration
violation. Under DHS regulations, ICE may conduct a worksite inspection so long as there is reasonable

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suspicion that there are aliens at the site who are “illegally in the United States” or “engaged in
unauthorized employment.”
Mirroring the Fourth Amendment’s restrictions, DHS regulations provide that an immigration officer
conducting an inspection may not enter the non-public areas of a business, a residence, a farm, or other
outdoor agricultural operation (excluding private lands near the border) to question the occupants or
employees about their immigration status in the absence of a judicial warrant or the property owner’s
consent. The immigration officer may enter publicly accessible parts of a business without any warrant,
consent, or reasonable suspicion of the unlawful presence of aliens. As noted above, the Supreme Court in
INS v. Delgado held that immigration officers who had legally entered worksites could briefly question
employees about their citizenship as long as the employees were not restrained. Some lower courts have
ruled that detaining employees during such questioning, without permitting them to leave, is
unconstitutional absent reasonable suspicion.
Congressional Activity
Several legislative proposals have been introduced in the 117th Congress concerning the scope and
limitations of ICE’s conduct of immigration enforcement actions. Some of these bills have sought to
statutorily constrain certain types of immigration enforcement activities. For example, the Protecting
Sensitive Locations Act (H.R. 529) would essentially codify ICE’s “sensitive locations” policy and
expand or clarify the range of locations where the agency may not engage in enforcement actions, to
expressly include law offices, domestic violence shelters, public assistance offices, places that provide
disaster or emergency services, congressional district offices, and school bus stops. The New Way
Forward Act (H.R. 536) and the Dignity for Detained Immigrants Act (S. 1186) would restrict ICE’s
ability to indefinitely detain aliens placed in formal removal proceedings and require the release from
custody of “vulnerable persons” (e.g., persons over 60 years of age, pregnant women, crime victims,
aliens who are found to have a credible fear of persecution) and “primary caregivers” (e.g., a parent or
close relative caring for or traveling with a child). In addition, the New Way Forward Act would require
ICE to establish Alternatives to Detention programs, limit the time period in which ICE may commence
formal removal proceedings against a removable alien, and prohibit state and local authorities from
engaging in immigration enforcement functions or otherwise assisting in the performance of such
functions. Similarly, the PROTECT Immigration Act (S. 1336) would bar ICE from entering into
agreements with state and local authorities to enforce federal immigration laws.
Other legislative proposals would expand ICE’s immigration enforcement powers. For instance, the
Criminal Alien Gang Member Removal Act (S. 1056) and the Protecting Our Communities from Gang
Violence Act (H.R. 1995) would broaden the classes of aliens who would be subject to removal or
mandatory detention (e.g., aliens associated with criminal gangs). Another bill, the Empowering Law
Enforcement Act (S. 1582) would give state and local law enforcement officials some immigration
enforcement powers and permit ICE to extend the detention of aliens who have committed certain
criminal offenses.

Author Information

Hillel R. Smith

Legislative Attorney

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Disclaimer
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LSB10362 · VERSION 3 · UPDATED

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