Understanding and Conceptualizing Domestic
December 29, 2023
Terrorism: Issues for Congress
Lisa N. Sacco
The federal government defines domestic terrorism (DT) as ideologically driven crimes
Analyst in Illicit Drugs and
committed by individuals in the United States that are intended to intimidate or coerce a civilian
Crime Policy
population or influence the policy or conduct of a government. Federal definitions of DT are

found in the USA PATRIOT Act (18 U.S.C. §2331), the Homeland Security Act (6 U.S.C. §101),
and Title 28 of the Code of Federal Regulations (§0.85). Aside from the statutory and regulatory

definitions of DT, the Federal Bureau of Investigation (FBI) has historically emphasized
particular qualities inherent to the actors who engage in DT. According to the FBI, domestic terrorists are Americans who
commit violence to achieve their goals that stem from domestic, extremist ideological influence, and lack foreign direction or
influence. This conceptualization excludes ideologically driven crimes committed in the United States by individuals whose
actions are directed or motivated by foreign groups.
How the federal government defines and conceptualizes DT shapes the nation’s understanding of it as criminal conduct and
as a policy issue. Domestic terrorists (and the crimes they commit) are labeled as such because their actions are directed
against the civilian population and/or U.S. government within the boundaries of the United States. Like foreign terrorism,
domestic terrorism involves ideologically driven criminal acts aimed at influencing the government or coercing the
population.
Unlike foreign terrorism, the federal government does not have a mechanism to formally charge an individual with DT,
which sometimes makes it difficult (and occasionally controversial) to formally characterize someone as a domestic terrorist.
Further, domestic terrorists may adhere to the ideologies of certain extremist movements or belong to hate or extremist
groups, but unlike the formal process involved in designating foreign terrorist organizations, DT movements and groups are
not officially labeled as such by the federal government, thereby making it difficult to categorize the threat presented by any
group or movement as a DT threat. While some observers may look to terrorism-related incidents, investigations, and arrests
to help understand the scope of the DT threat, these data are limited.
DT incidents have a low occurrence rate but high impact, and the federal government has a significant role in combatting the
threat of DT. In 2021, the FBI and the Department of Homeland Security (DHS) issued the nation’s first national strategy for
countering the DT threat. The strategy identifies DT threats to include potentially unlawful use or threats of force or violence
in furtherance of ideological agendas from racially or ethnically motivated violent extremists, anti-government or anti-
authority violent extremists (further broken down to include militia violent extremists, anarchist violent extremists, and
sovereign citizen violent extremists), animal rights/environmental violent extremists, and abortion-related violent extremists.
How the government defines and combats DT and extremism is complicated for many reasons. Believing in or expressing
extremist ideals and/or vocalizing support for DT incidents are not violations of federal law. If an individual in the United
States espouses extremist beliefs, such as anarchy or the superiority of the white race, that behavior is generally protected
speech under the First Amendment. Expressions of these beliefs sometimes precede DT incidents, and in hindsight some may
question why these incidents could not be prevented. Crossing the line from First Amendment-protected activity, such as a
peaceful protest, to DT-related violence can happen quickly; however, there is often little law enforcement can do in response
to extremist but protected speech.
Despite the statutory definition of DT in Title 18 of the U.S. Code, no federal criminal provision expressly prohibits
“domestic terrorism.” While DT is defined in federal statute, the term domestic terrorist is not used to officially label any
group (as it is with foreign terrorist organizations). However, federal law enforcement has referred (in some instances such as
congressional testimony) to individuals as domestic terrorists and their crimes as DT.
Going forward, Congress may consider any number of legislative options regarding the federal government’s approach to
defining and confronting DT, including (1) enactment of a DT charging statute; (2) the utility and consequences of applying
the DT label in federal policy; (3) allocation of additional, less, or equivalent appropriations to address DT; and (4)
adjustments to DT data collection requirements for federal agencies.
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Introduction
How the federal government defines and conceptualizes domestic terrorism (DT)1 shapes the
nation’s understanding of it as a federal crime and policy issue. Domestic terrorists (and the
crimes they commit) are labeled as such because their criminal actions are directed against the
civilian population and/or government and intended to influence the conduct of government
within the boundaries of the United States. Like foreign terrorism, DT involves ideologically
driven criminal acts aimed at influencing the government or coercing the population. But unlike
with foreign terrorism, the federal government currently cannot formally charge individuals with
DT, which sometimes makes it difficult (and occasionally controversial) for the federal
government to formally characterize any individual as a domestic terrorist. Further, domestic
terrorists may adhere to certain extremist ideologies or belong to hate or extremist groups, but
unlike the formal process involved in designating foreign terrorist organizations, the federal
government does not have a formal process to label domestic terrorist movements or groups,
thereby making it difficult to categorize the threat presented by groups or movements as a DT
threat. Some observers may look to terrorism-related incidents, investigations, and arrests to help
them understand the scope of the DT threat, but these data are limited (see the “Domestic
Terrorism Data” section).
Over the past several years, Congress has addressed DT through hearings, appropriations, and
legislation. Further, Congress experienced an act of DT at the U.S. Capitol while Members were
in session on January 6, 2021.2 This report examines DT as a federal policy issue, analyzes DT
threats and incidents, and discusses issues Congress may consider as it deliberates the federal
government’s approach to defining and confronting DT.
Defining Domestic Terrorism and Extremism
In addition to statutory definitions of DT, the federal government has further defined and
conceptualized DT through policy. The Federal Bureau of Investigation (FBI) has defined DT as
ideologically driven crimes committed by individuals in the United States that lack foreign
direction or influence.3 This conceptualization excludes individuals directed or motivated by
foreign groups such as Al Qaeda or the Islamic State.4 Further, the U.S. government does not
provide a precise, comprehensive, and public explanation of any particular groups it might
consider to be domestic terrorist organizations. Listing groups in this way may infringe on First
Amendment-protected free speech—or the act of belonging to an ideological group, which in and
of itself is not a crime in the United States. Instead, the FBI and Department of Homeland
Security (DHS) have identified a number of general DT threats, and they categorize the threats
according to specific extremist beliefs. The ideological concepts underlying such threats may

1 This report largely focuses on DT as a federal crime.
2 See comments made by FBI Director Wray in U.S. Congress, Senate Committee on the Judiciary, Oversight of the
Federal Bureau of Investigation: the January 6 Insurrection, Domestic Terrorism, and Other Threats, hearing, 117th
Cong., 1st sess., March 2, 2021. For CRS analysis of the attack on the U.S. Capitol on January 6, 2021, see CRS Insight
IN11573, Domestic Terrorism and the Attack on the U.S. Capitol.
3 James F. Jarboe, then-Domestic Terrorism Section Chief, Counterterrorism Division, FBI, Testimony Before the
House Resources Committee, Subcommittee on Forests and Forest Health, February 12, 2002; and Council on Foreign
Relations, A Conversation with Christopher Wray, April 26, 2019, https://www.cfr.org/event/conversation-christopher-
wray-0.
4 For more information about Al Qaeda, see CRS In Focus IF11854, Al Qaeda: Background, Current Status, and U.S.
Policy. For more information about the Islamic State, see CRS In Focus IF10328, The Islamic State.
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inspire criminal activity, such as hate crimes, that does not rise to the level of terrorism—but
occasionally they do. The threshold for when a hate crime incident rises to the level of DT and the
government decision to label it as such are not always clear (see “Hate Crimes as Domestic
Terrorism Incidents”).
In the National Defense Authorization Act for Fiscal Year 2020 (NDAA FY2020; P.L. 116-92),
Congress directed the FBI Director and DHS Secretary, in consultation with the Director of
National Intelligence, to develop uniform definitions of DT and other related terms for the
purpose of recordkeeping and tracking related data. The NDAA FY2020 also required that the
FBI and DHS issue an annual strategic intelligence assessment and report on DT. These
definitions and assessments are referenced throughout this CRS report.
Federal Definitions of Domestic Terrorism
In general statutory terms, a domestic terrorist
engages in terrorist activity that occurs in the
Federal Agencies Responsible for
United States. The FBI and DHS rely on
Countering Domestic Terrorism
statutory and regulatory definitions to identify
The FBI has lead responsibility for federal terrorism
incidents as DT or individuals as domestic
investigations.5 Its Counterterrorism Division has a DT
terrorists. The FBI generally relies on two
Operations Section comprised of special agents,
fundamental sources to define DT. First, the
intelligence analysts, and professional staff. Other
federal agencies such as the Bureau of Alcohol,
Code of Federal Regulations characterizes
Tobacco, Firearms, and Explosives and other
terrorism as including “the unlawful use of
Department of Justice (DOJ) agencies; the Internal
force and violence against persons or property
Revenue Service; and agencies within DHS also play a
to intimidate or coerce a government, the
role in enforcement efforts to counter DT. These
agencies—as well as state and local law enforcement
civilian population, or any segment thereof, in
representatives—typically cooperate within the
furtherance of political or social objectives.”8
framework of Joint Terrorism Task Forces (JTTFs),
Second, 18 U.S.C. §2331(5) more narrowly
multiagency investigative units led by DOJ and the FBI
defines domestic terrorism and differentiates it
across the country.6
from international terrorism and other criminal
Federal agencies such as those within DHS also support
activity. This definition comes from Section
community-level and individual-level resilience to DT
and extremist violence. They provide financial,
802 of the Uniting and Strengthening America
technical, and educational assistance to those who are
by Providing Appropriate Tools Required to
“well placed to recognize and address possible
Intercept and Obstruct Terrorism Act (USA
domestic terrorism recruitment and mobilization to
PATRIOT Act) of 2001 (P.L. 107-56).
violence.”7
According to 18 U.S.C. §2331(5), DT occurs
primarily within U.S. territorial jurisdiction and involves:

5 28 C.F.R. §0.85. The FBI exercises lead agency responsibility in investigating all crimes for which it has primary or
concurrent jurisdiction and that involve terrorist activities or acts in preparation of terrorist activities within the
statutory jurisdiction of the United States.
6 FBI and DHS, Strategic Intelligence Assessment and Data on Domestic Terrorism, June 2023, p. 28,
https://www.fbi.gov/file-repository/fbi-dhs-domestic-terrorism-strategic-report-2023.pdf (hereinafter, “Strategic
Intelligence Assessment and Data on Domestic Terrorism, 2023”). For more information on JTTFs, see FBI, Joint
Terrorism Task Forces, https://www.fbi.gov/investigate/terrorism/joint-terrorism-task-forces; and DHS, U.S.
Immigration and Customs Enforcement, Joint Terrorism Task Force: Supporting the Global Fight Against Terrorism,
https://www.ice.gov/partnerships-centers/jttf.
7 The White House, National Security Council, National Strategy for Countering Domestic Terrorism, June 2021, p.
20, https://www.whitehouse.gov/wp-content/uploads/2021/06/National-Strategy-for-Countering-Domestic-
Terrorism.pdf (hereinafter, National Strategy for Countering Domestic Terrorism).
8 28 C.F.R. §0.85.
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(A) ... acts dangerous to human life that are a violation of the criminal laws of the United
States or of any State;
(B) appear to be intended—
(i) to intimidate or coerce a civilian population;
(ii) to influence the policy of a government by intimidation or coercion; or
(iii) to affect the conduct of a government by mass destruction, assassination, or
kidnapping....
In their 2022 report to Congress containing strategic intelligence assessment and DT data (in
describing its methodology for classifying acts of DT), the FBI described DT as “an
ideologically-driven criminal act, including threats made to or acts of violence against specific
victims, in furtherance of a domestic political and/or social goal.”9 In their 2023 report, the FBI
removed “ideologically-driven” from this definition among other changes: “[t]he FBI defines a
‘DT incident’ as a criminal act, including threats or acts of violence to specific victims, made in
furtherance of a domestic political and/or social goal, which has occurred and can be
confirmed.”10
Aside from the statutory and regulatory definitions of DT, the FBI has historically emphasized
particular qualities inherent to the actors who engage in it. According to the FBI, domestic
terrorists are Americans who commit violence to achieve their goals that stem from domestic,
extremist ideological influences.11 The FBI identifies and categorizes certain extremist
ideological influences to define and describe the DT threat.
For its use of the term domestic terrorism, DHS relies on the definition of terrorism from the
Homeland Security Act (HSA; 6 U.S.C. §101(18)), which is substantially similar, but not
identical, to 18 U.S.C. §2331(5). It states that terrorism is any activity that:
(A) involves an act that—
(i) is dangerous to human life or potentially destructive of critical infrastructure or key
resources; and
(ii) is a violation of the criminal laws of the United States or of any State or other
subdivision of the United States; and
(B) appears to be intended—
(i) to intimidate or coerce a civilian population;
(ii) to influence the policy of a government by intimidation or coercion; or
(iii) to affect the conduct of a government by mass destruction, assassination, or
kidnapping.

9 FBI and DHS, Strategic Intelligence Assessment and Data on Domestic Terrorism, October 2022, p. 5,
https://www.dhs.gov/sites/default/files/2022-10/22_1025_strategic-intelligence-assessment-data-domestic-
terrorism.pdf (hereinafter, “Strategic Intelligence Assessment and Data on Domestic Terrorism, 2022”).
10 Strategic Intelligence Assessment and Data on Domestic Terrorism, 2023, p. 5.
11 Michael C. McGarrity, Statement Before the House Homeland Security Committee, FBI, May 8, 2019,
https://www.fbi.gov/news/testimony/confronting-the-rise-of-domestic-terrorism-in-the-homeland (hereinafter, “FBI
McGarrity testimony, May 2019”); FBI, “Domestic Terrorism in the Post-9/11 Era,” September 7, 2009; James F.
Jarboe (then Domestic Terrorism Section Chief, Counterterrorism Division), FBI, Testimony Before the House
Resources Committee, Subcommittee on Forests and Forest Health, February 12, 2002.
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Unlike the USA PATRIOT Act, this definition from the HSA specifically includes acts that are
potentially destructive to critical infrastructure and does not specifically refer to domestic
terrorism.
In describing its methodology for classifying acts of DT, the DHS Office of Intelligence and
Analysis (I&A) defines a DT attack as “an incident motivated by a DVE [domestic violent
extremist] ideology in which a weapon or tactic is purposefully deployed against a target for the
purpose of causing injury, death, or property destruction.”12 In distinguishing DHS’s methodology
from the FBI’s, both the FBI and DHS explain:
these ideologically driven criminal acts must be dangerous to human life or potentially
destructive to critical infrastructure or key resources to meet the definition of DT. A single
incident may be part of a spree of criminal or violent activity conducted by the same
perpetrator(s) using the same tactic(s), which are carried out against multiple locations in
short succession.13
DHS’s inclusion of physical threats to “critical infrastructure or key resources” sets it apart from
the FBI’s definition of DT.
Federal Definitions of Domestic Violent Extremism
In recent years, both the FBI and DHS have categorized the DT threat by types of extremism, and
more specifically, domestic violent extremism. In Domestic Terrorism: Definitions, Terminology,
and Methodology, released in 2020, they list and describe the DT threat categories as follows:
Racially or Ethnically Motivated Violent Extremism: This threat encompasses the
potentially unlawful use or threat of force or violence in furtherance of ideological agendas
derived from bias, often related to race or ethnicity, held by the actor against others or a
given population group. Racially or Ethnically Motivated Violent Extremists purport to use
both political and religious justifications to support their racially- or ethnically-based
ideological objectives and criminal activities.
Anti-Government or Anti-Authority Violent Extremism: This threat encompasses the
potentially unlawful use or threat of force or violence in furtherance of ideological agendas,
derived from anti-government or anti-authority sentiment, including opposition to
perceived economic, social, or racial hierarchies, or perceived government overreach,
negligence, or illegitimacy.
Animal Rights/Environmental Violent Extremism: This threat encompasses the
potentially unlawful use or threat of force or violence in furtherance of ideological agendas
by those seeking to end or mitigate perceived cruelty, harm, or exploitation of animals
and/or the perceived exploitation or destruction of natural resources and the environment.
Abortion-Related Violent Extremism: This threat encompasses the potentially unlawful
use or threat of force or violence in furtherance of ideological agendas relating to abortion,
including individuals who advocate for violence in support of either pro-life or pro-choice
beliefs.
All Other Domestic Terrorism Threats: This category encompasses threats involving
the potentially unlawful use or threat of force or violence in furtherance of ideological
agendas which are not otherwise defined under or primarily motivated by one of the other
Domestic Terrorism threat categories. Such agendas could flow from, but are not limited
to, a combination of personal grievances and beliefs, including those described in the other

12 Strategic Intelligence Assessment and Data on Domestic Terrorism, 2023, p. 6.
13 Ibid.
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Domestic Terrorism threat categories. Some actors in this category may also carry bias
related to religion, gender, or sexual orientation.14
In their 2023 annual report, Strategic Intelligence Assessment and Data on Terrorism (hereinafter
referred to as Strategic Intelligence Assessment, with the respective year of the report), the FBI
and DHS rely on and amend/update the language in these categories to describe the DT threat,
and also define the term domestic violent extremist (DVE). The report defines a DVE as follows:
an individual based and operating primarily within the United States or its territories
without direction or inspiration from a foreign terrorist group or other foreign power who
seeks to further political or social goals, wholly or in part, through unlawful acts of force
or violence dangerous to human life.15
One apparent difference between the definitions of a DVE and domestic terrorist is that a DVE
seeks to further political or social goals through unlawful violence while a domestic terrorist goes
so far as to plan or commit acts of violence. In the aforementioned report, the FBI and DHS stress
that “mere advocacy of political or social positions, political activism, use of strong rhetoric, or
generalized philosophic embrace of violent tactics does not constitute extremism, and is
constitutionally protected.”16 The FBI and DHS acknowledge that the I&A uses the term domestic
terrorist interchangeably with domestic violent extremist.17
In the Strategic Intelligence Assessment, 2021, the FBI and DHS further break down the anti-
government/anti-authority violent extremism (-ist) category as follows:
Militia Violent Extremists: DVEs who take overt steps to violently resist or facilitate the
overthrow of the US Government in support of their belief that the US Government is
purposely exceeding its Constitutional authority and is trying to establish a totalitarian
regime; oppose many federal and state laws and regulations, particularly those related to
firearms ownership.
Anarchist Violent Extremists: DVEs who oppose all forms of capitalism, corporate
globalization, and governing institutions, which are perceived as harmful to society.
Sovereign Citizen Violent Extremists: DVEs who believe they are immune from
government authority and laws.18
The FBI and DHS have added further details about these extremists, but did not again define
them in subsequent Strategic Intelligence Assessment reports. For example, in the Strategic
Intelligence Assessment, 2023, the FBI and DHS add the following details for abortion-related
violent extremists: “[a]bortion-related violent extremists (AbRVEs) – both pro-life and pro-choice
– have threatened, vandalized, and impeded access to facilities that provide reproductive health
services or counseling, which can violate the Freedom of Access to Clinic Entrances Act.”19

14 FBI and DHS, Domestic Terrorism: Definitions, Terminology, and Methodology, November 2020,
https://www.fbi.gov/file-repository/fbi-dhs-domestic-terrorism-definitions-terminology-methodology.pdf/view.
15 Strategic Intelligence Assessment and Data on Domestic Terrorism, 2023, p. 4.
16 Strategic Intelligence Assessment and Data on Domestic Terrorism, 2023, p. 4; and Strategic Intelligence
Assessment and Data on Domestic Terrorism, 2022, p. 4. In the 2021 report, the FBI and DHS less affirmatively say
that advocacy may not constitute extremism and may be constitutionally protected. See FBI and DHS, Strategic
Intelligence Assessment and Data on Domestic Terrorism, May 2021, p. 4, https://www.fbi.gov/file-repository/fbi-dhs-
domestic-terrorism-strategic-report.pdf (hereinafter, “Strategic Intelligence Assessment and Data on Domestic
Terrorism, 2021”).
17 FBI and DHS, Domestic Terrorism: Definitions, Terminology, and Methodology, November 2020,
https://www.fbi.gov/file-repository/fbi-dhs-domestic-terrorism-definitions-terminology-methodology.pdf, p. 2.
18 Strategic Intelligence Assessment and Data on Domestic Terrorism, 2021, p. 5.
19 Strategic Intelligence Assessment and Data on Domestic Terrorism, 2023, p. 10.
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Law enforcement officials often use the term domestic violent extremists to describe the actors (or
the alleged actors) while using domestic terrorism to describe the acts. For example, FBI Director
Christopher Wray, in describing the January 6, 2021, attack on the U.S. Capitol, has referred to
the individuals who engaged in violent criminal activity as violent extremists and has described
the incident as DT:
Certainly the Capitol attack involved violent extremist[s]. As I said we the FBI consider
this a form of domestic terrorism. It included a variety of backgrounds, certainly there were
quite a number—we are seeing quite a number as we are building out the cases on the
individuals we have arrested for the violence quite a number who what we would call sort
of militia violent extremists so we’ve got a number who self-identify with you know the
Proud Boys or the Oath Keepers, things like that. And we also have a couple of instances
where we have already identified individuals involved in the criminal behavior who we
would put in the racially motivated violent extremists who advocate for what you would
call CERT of white supremacy so there have been some of those individuals as well.20
The National Strategy for Countering Domestic Terrorism
In June 2021, President Biden and the National Security Council released the first U.S. strategy to address DT. The
strategy points to the statutory definition of DT in Title 18 of the U.S. Code and highlights that federal DT law
does not distinguish between political views.21 In noting violent domestic terrorist attacks by individuals motivated
by a range of ideologies, the strategy emphasizes that “racially or ethnically motivated violent extremists
(principally those who promote the superiority of the white race) and militia violent extremists are assessed as
presenting the most persistent and lethal threats.”22
Federal Domestic Terrorism Laws
DT is not a chargeable federal offense. While an individual may commit crimes that are widely
considered to be acts of DT, they cannot be charged at the federal level with committing an act of
DT because there is no federal criminal provision expressly prohibiting domestic terrorism. For
example, Timothy McVeigh, widely considered a domestic terrorist in the United States,23 was
never charged with or convicted of DT. Instead, he was convicted of murder, conspiracy, and
using a weapon of mass destruction in the 1995 bombing of the Alfred P. Murrah Federal
Building in Oklahoma City that killed 168 people.24 Some states have DT laws,25 and individuals
who commit certain offenses in those states may face prosecution for DT under state law.26 For

20 Comments made by FBI Director Wray in U.S. Congress, Senate Committee on the Judiciary, Oversight of the
Federal Bureau of Investigation: the January 6 Insurrection, Domestic Terrorism, and Other Threats, hearing, 117th
Cong., 1st sess., March 2, 2021.
21 National Strategy for Countering Domestic Terrorism, p. 13.
22 Ibid., p. 6.
23 For more information on Timothy McVeigh and the Oklahoma City DT incident in 1995, see FBI, Oklahoma City
Bombing, https://www.fbi.gov/history/famous-cases/oklahoma-city-bombing; and Lou Michel and Dan Herbeck,
American Terrorist: Timothy McVeigh and the Oklahoma City Bombing (Harper, 2001).
24 Lois Romano and Tom Kenworthy, “McVeigh Guilty on All 11 Counts,” The Washington Post, June 3, 1997.
25 For a comprehensive list of state DT laws, see International Center for Not-For-Profit Law, State Domestic
Terrorism Laws in the United States, October 2023, https://www.icnl.org/post/analysis/state-domestic-terrorism-laws-
in-the-united-states.
26 Shirin Sinnar, Separate and Unequal: The Law of “Domestic” and “International” Terrorism, 117 MICH. L. REV.
1333, 1353–54 (2019): “In practice, state-level prosecutions for conduct that could be classified as terrorism generally
proceed using conventional criminal charges.”
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example, in 2019 James Jackson was convicted of DT as well as other crimes in New York for the
“white supremacist murder” of Timothy Caughman.27
While there is no federal criminal offense that expressly prohibits DT, several federal statutes and
the U.S. Sentencing Guidelines provide for increased penalties if DT is involved in a chargeable
offense. For example, Section 111 of Title 18 of the U.S. Code authorizes various prison terms28
for forcibly assaulting, resisting, opposing, impeding, intimidating, or interfering with certain
federal officers or employees.29 If an individual commits such an offense, and it involves acts of
international or domestic terrorism as defined in 18 U.S.C. §2331(5), federal law authorizes
imprisonment for up to an additional eight years.30 For a discussion of how the courts have
applied this and other DT-related sentence enhancements, see CRS Report R46829, Domestic
Terrorism: Overview of Federal Criminal Law and Constitutional Issues.
Despite the absence of a specific federal DT charging statute, the FBI describes some acts as DT,
some investigations as DT investigations, and some individuals as “DT subjects” arrested for
applicable criminal violations or “subjects included within the domestic terrorism program.”31 As
mentioned previously, FBI Director Wray is quoted as saying that the attack on the U.S. Capitol
on January 6 was DT: “That attack—that siege, was criminal behavior, plain and simple, and it
was behavior that we, the FBI, view [as] domestic terrorism.”32 To date, most federal charges33
against accused participants in the attack range from vandalism of government property34 to
seditious conspiracy,35 and most do not include DT nor any sentencing enhancement related to
DT.36 In some cases, judges have rejected prosecutors’ requests for a DT sentencing
enhancement.37 However, in May 2023 Stewart Rhodes (founder of the Oath Keepers, a militant

27 Manhattan District Attorney’s Office, D.A. Vance Secures Domestic Terrorism Conviction of James Jackson For
White Supremacist Murder of Timothy Caughman, January 23, 2019.
28 Acts under the statute that qualify as only “simple assault” are punishable by up to one year in prison, while acts that
“involve physical contact with the victim of that assault or the intent to commit another felony” are punishable by
imprisonment for up to eight years. 18 U.S.C. §111(a). Use of a deadly or dangerous weapon or infliction of bodily
injury enhances the applicable penalty to up to 20 years in prison. 18 U.S.C. §111(b).
29 18 U.S.C. §111.
30 For more information on this offense, see CRS Report RL34303, Obstruction of Justice: An Overview of Some of the
Federal Statutes That Prohibit Interference with Judicial, Executive, or Legislative Activities.
31 Strategic Intelligence Assessment and Data on Domestic Terrorism, 2023, p. 26; and Strategic Intelligence
Assessment and Data on Domestic Terrorism, 2022, p. 21.
32 Comments made by FBI Director Wray in U.S. Congress, Senate Committee on the Judiciary, Oversight of the
Federal Bureau of Investigation: the January 6 Insurrection, Domestic Terrorism, and Other Threats, hearing, 117th
Cong., 1st sess., March 2, 2021.
33 For more information on charges against the accused participants in the January 6, 2021, attack on the U.S. Capitol,
see DOJ, Capitol Breach Investigation Resource Page, https://www.justice.gov/usao-dc/capitol-breach-cases. For legal
discussion of three specific categories of federal criminal statutes that may have been violated by some of the
participants, see CRS Legal Sidebar LSB10564, Federal Criminal Law: January 6, 2021, Unrest at the Capitol.
34 See 18 U.S.C. §1361.
35 See 18 U.S.C. §2384.
36 For one of the accused participants in the January 6 attack on the U.S. Capitol, the FBI and DOJ used a DT provision
in Section 219 of the USA PATRIOT Act (P.L. 107-56) to request a search warrant from a U.S. magistrate judge
outside of the district where the suspect and property in question reside. See In the Matter of the Search of One Apple
iPhone Smartphone that is Currently Being Carried on the Person of Undisclosed Name, Under Rule 41, Case No. 21-
sw-253 (ZMF) Under Seal (United States District Court for the District of Columbia). According to the opinion,
Section 219 of the USA PATRIOT Act “empowers a judge to issue an extraterritorial warrant ‘in an investigation of
domestic terrorism or international terrorism’ so long as ‘activities related to the terrorism may have occurred’ in the
issuing district.”
37 Kyle Cheney and Josh Gerstein, “Judge rejects ‘terrorism’ sentencing enhancement for leader of Jan. 6 tunnel
(continued...)
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group as described by Director Wray)38 was sentenced for crimes committed on January 6, and
his sentence was enhanced for involving acts of DT; Judge Amit Mehta noted that Rhodes’
actions met the legal definition of terrorism.39 Since Rhodes’ sentencing, the DT sentence
enhancement has been applied several times more for crimes related to January 6.40
Domestic Terrorism Threats
The FBI and DHS do not officially designate domestic terrorist organizations,41 but they openly
delineate domestic terrorist threats. As discussed previously, the U.S. Department of Justice
(DOJ) identifies DT threats to include potentially unlawful use or threat of force or violence in
furtherance of ideological agendas from racially or ethnically motivated violent extremists, anti-
government or anti-authority violent extremists (further broken down to include militia violent
extremists, anarchist violent extremists, and sovereign citizen violent extremists), animal
rights/environmental violent extremists, and abortion-related violent extremists.42
In explaining to the public how they investigate terrorism, the FBI describes the DT threat as
persistent, with actors “crossing the line from exercising First Amendment-protected rights to
committing crimes in furtherance of violent agendas.”43 Crossing the line from First Amendment-
protected activity, such as a peaceful protest, to DT-related violence can happen quickly. In 2020,
for example, violence and rioting broke out at protests across the country (many occurring in
Portland, OR) that had previously been peaceful.44 Then-Attorney General William P. Barr said at
the time, “The violence instigated and carried out by Antifa and other similar groups in
connection with the rioting is domestic terrorism and will be treated accordingly.”45 DOJ

confrontation,” Politico, February 27, 2023, https://www.politico.com/news/2023/02/27/judge-rejects-terrorism-
sentencing-jan-6-00084592; and Daniel Barnes and Ryan J. Reilly, “Capitol rioter Guy Reffitt gets longest Jan. 6
sentence, but no terrorism enhancement,” NBC News, August 1, 2022, https://www.nbcnews.com/politics/justice-
department/capitol-rioter-guy-reffitt-gets-longest-jan-6-sentence-no-terrorism-en-rcna40664.
38 U.S. Congress, Senate Committee on the Judiciary, Oversight of the Federal Bureau of Investigation: the January 6
Insurrection, Domestic Terrorism, and Other Threats, hearing, 117th Cong., 1st sess., March 2, 2021.
39 For more information on this case, see DOJ, Court Sentences Two Oath Keepers Leaders to 18 Years in Prison on
Seditious Conspiracy and Other Charges Related to U.S. Capitol Breach, May 25, 2023, https://www.justice.gov/usao-
dc/pr/court-sentences-two-oath-keepers-leaders-18-years-prison-seditious-conspiracy-and-other.
40 DOJ, Two Leaders of the Proud Boys Sentenced to 17 and 15 Years in Prison on Seditious Conspiracy and Other
Charges Related to U.S. Capitol Breach, August 31, 2023, https://www.justice.gov/opa/pr/two-leaders-proud-boys-
sentenced-17-and-15-years-prison-seditious-conspiracy-and-other.
41 While the government does not provide an official and public list of domestic terrorist organizations, it does include
known or suspected terrorists (to include international and domestic terrorists) in its Threat Screening System (formerly
known as the Terrorist Screening Database and commonly known as the Terrorist Watchlist.) See FBI, Terrorist
Screening Center, “Frequently Asked Questions,” https://ucr.fbi.gov/nsb/tsc/terrorist-screening-center-frequently-
asked-questions-032416.pdf; and FBI, Terrorist Screening Center, https://www.fbi.gov/investigate/terrorism/tsc.
42 In recent years, the FBI switched from using the term anti-abortion to abortion-related extremism, thus including
individuals who may commit crimes to protect abortion rights. For an example of how the FBI previously applied the
term anti-abortion extremism or extremist, see FBI, Terrorism 2002/2005, https://www.fbi.gov/stats-services/
publications/terrorism-2002-2005. For an example of how FBI applies the term abortion-related violent extremism, see
Strategic Intelligence Assessment and Data on Domestic Terrorism, 2023.
43 FBI, What We Investigate, https://www.fbi.gov/investigate/terrorism (accessed on November 15, 2023).
44 For a discussion of federal law enforcement and the Portland, OR, protests in 2020, see CRS Legal Sidebar
LSB10529, Federal Law Enforcement and the Portland Protests: Legal Considerations.
45 DOJ, Attorney General William P. Barr’s Statement on Riots and Domestic Terrorism, May 31, 2020,
https://www.justice.gov/opa/pr/attorney-general-william-p-barrs-statement-riots-and-domestic-terrorism.
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responded by engaging its JTTFs and charging many of those who engaged in violence with
violations of federal law.46
Former Methods of Describing Threats
The FBI’s descriptions of DT have evolved. In previous descriptions of the DT threat, the FBI has
used the terms ecoterrorists, black separatists, white supremacists, and abortion extremists.47
Also in past descriptions of the DT threat, the FBI distinguished between special interest
terrorism and traditional right-wing and left-wing terrorism. For instance, in congressional
testimony in 2002, James Jarboe, former Domestic Terrorism Section Chief of the FBI’s
Counterterrorism Division, described special interest terrorism as follows:
Special interest terrorism differs from traditional right-wing and left-wing terrorism in that
extremist special interest groups seek to resolve specific issues, rather than effect
widespread political change. Special interest extremists continue to conduct acts of
politically motivated violence to force segments of society, including the general public,
to change attitudes about issues considered important to their causes. These groups occupy
the extreme fringes of animal rights, pro-life, environmental, anti-nuclear, and other
movements.48
It is unclear whether any FBI materials currently use the categories of special interest, left-wing,
and right-wing terrorism, but they have not appeared in recent FBI reports or testimony. Labeling
terrorism in such a manner is discussed further in the “Utility of Using the Domestic Terrorism
Term” section.
Current Threats—Extremists and Lone Actors
According to the FBI, the DT threat “expanded significantly” in 2021 and 2022.49 As it had in
previous years, the FBI concluded that the increase is largely attributable to an escalating threat
from DVEs and an increase in anti-government or anti-authority violent extremism. DHS has
echoed this conclusion and states that DVEs present the “most persistent and lethal threat” to the
homeland, and it has designated domestic violent extremism as a “national priority area” for its
Homeland Security Grant Program (HSGP).50 FBI Director Wray stated that “[t]rends may shift,
but the underlying drivers for domestic violent extremism—such as perceptions of government or
law enforcement overreach, sociopolitical conditions, racism, anti-Semitism, Islamophobia,
misogyny, and reactions to legislative actions—remain constant.”51

46 Ibid; and DOJ, “74 People Facing Federal Charges for Crimes Committed During Portland Demonstrations: Charges
Include Assaulting Federal Officers, Arson, Failing to Obey Lawful Orders, and Damaging Government Property,”
August 27, 2020, https://www.justice.gov/usao-or/pr/74-people-facing-federal-charges-crimes-committed-during-
portland-demonstrations.
47 DOJ, Counterterrorism White Paper, June 22, 2006, p. 59. See also FBI, “What Are Known Violent Extremist
Groups?”. The FBI’s former website was captioned “Don’t Be a Puppet,” and addressed teenagers. It succinctly
described numerous violent extremist groups or ideologies, but is no longer publicly available.
48 James F. Jarboe (then Domestic Terrorism Section Chief, Counterterrorism Division), FBI, Testimony Before the
House Resources Committee, Subcommittee on Forests and Forest Health, February 12, 2002.
49 FBI, FY2023 President’s Budget Request, March 2022, p. 68.
50 DHS, Homeland Threat Assessment, October 2020, p. 17; and DHS, Summary of the Terrorism Threat to the United
States, National Terrorism Advisory System Bulletin, June 7, 2022, https://www.dhs.gov/sites/default/files/ntas/alerts/
22_0607_S1_NTAS-Bulletin_508.pdf. For more information about the HSGP, see DHS, Homeland Security Grant
Program, https://www.dhs.gov/homeland-security-grant-program-hsgp.
51 FBI Director Christopher Wray, Worldwide Threats to the Homeland: Statement for the Record, Statement Before
(continued...)
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In the Strategic Intelligence Assessment and Data on Domestic Terrorism, budget documents, and
FBI testimony regarding the DT threat over the last several years, the FBI has stated that it is
most concerned about lone actors and small groups of individuals, primarily using firearms and
easily accessible weapons.52 According to the FBI, these individuals “act without a clear group
affiliation or guidance, making them challenging to identify, investigate, and disrupt” and they
often radicalize online.53 The decentralized and fluid nature of the threat from lone actors who
may quickly mobilize to action presents a significant challenge to law enforcement in seeking to
prevent terrorist incidents.54
Domestic Terrorism Incidents
As compared to other violent crimes, DT incidents occur less frequently,55 but when they do
occur they often have high impact. Federal law enforcement officials and researchers generally
agree that the number of DT incidents has risen in recent years, but government statistics on these
incidents are limited (see the “Domestic Terrorism Data” section).56 In 2021 and 2022, the FBI
published data on DT-related charges from 2015-2021 as required by the National Defense
Authorization Act for Fiscal Year 2020 (NDAA FY2020; P.L. 116-92). While these data show the
number of referrals to the FBI for possible DT incidents pending FBI DT investigations, and the
number of subjects arrested for DT-related charges (see Table 1), they do not provide a
comprehensive understanding of DT in the United States. Additional details, such as which
underlying offenses precisely qualify as DT-related charges,57 the location of incidents, and the
relevant category of extremism would help provide a more comprehensive understanding of the
nature and extent of DT-related crimes in the United States.

the House Homeland Security Committee, September 17, 2020, https://www.fbi.gov/news/testimony/worldwide-
threats-to-the-homeland-091720.
52 In the Strategic Intelligence Assessment and Data on Domestic Terrorism, 2021, the FBI and DHS called the threat
from lone offenders the “greatest terrorism threat to the Homeland we face today.” In subsequent assessments in 2022
and 2023, they labeled the threat as “one of the most significant terrorism threats to the United States we face today.”
See Strategic Intelligence Assessment and Data on Domestic Terrorism, 2023, p. 2; Strategic Intelligence Assessment
and Data on Domestic Terrorism, 2022, p. 2; and Strategic Intelligence Assessment and Data on Domestic Terrorism,
2021, p. 2.
53 Ibid.; FBI, McGarrity testimony, May 2019; and FBI, FY2023 President’s Budget Request, March 2022, p. 68.
54 National Strategy for Countering Domestic Terrorism, p. 9.
55 While DT data are limited in several ways (see the “Domestic Terrorism Data” section of this report), based on what
is known about violent crime in the United States, DT incidents occur less frequently than most other violent crimes.
56 FBI Director Christopher Wray, Federal Bureau of Investigation Budget Request for Fiscal Year 2023, Statement
Before the Senate Appropriations Committee, Subcommittee on Commerce, Justice, Science, and Related Agencies,
May 25, 2022, https://www.fbi.gov/news/testimony/federal-bureau-of-investigation-budget-request-for-fiscal-year-
2023; and William Braniff, Countering Domestic Terrorism: Examining the Evolving Threat, National Consortium for
the Study of Terrorism and Responses to Terrorism (START), Testimony before the House Homeland Security and
Governmental Affairs Committee, September 25, 2019, p. 3.
57 The FBI and DHS provide examples of federal statutes that reach conduct associated with DT depending on the
circumstances of the crimes. They state that some federal criminal statutes on their face relate to DT (such as aircraft
sabotage and bombing of federal property) while others do not. See Strategic Intelligence Assessment and Data on
Domestic Terrorism, 2023, p. 26.
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Table 1. Number of Individuals Arrested with DT-Related Charges, Pending DT
Investigations, and Referrals of Possible DT Incidents
FY2015–FY2022

FY2015
FY2016
FY2017
FY2018
FY2019
FY2020
FY2021
FY2022
Number of DT
subjects arrested
by or in
130
169
109
61
65
NA
NA
NA
coordination
with FBI with
federal chargesa
Number of DT
subjects arrested
by or in
coordination
81
60
77
59
44
NA
NA
NA
with FBI charged
with state/local
chargesa
Total number
of subjects
with state or
211
229
186
113
107
180
800
400
federal DT-
related
chargesb
Number of
referrals to FBI of
NA
NA
NA
NA
675
5,669
8,375
5,772
possible DT
incidentsc
Number of
referrals of
possible DT
incidents from
NA
NA
NA
NA
NA
1,287
1,399
1,118
FBI to federal
and/or SLTTd
partners
Number of DT
incidents the FBI
converted to
NA
NA
NA
NA
NA
747
1,525
394
preliminary or
ful DT
investigations
Approximate
number of
NA
NA
1,000
1,000
1,000
1,400
2,700
2,700
pending FBI DT
investigationse
Source: Federal Bureau of Investigation and U.S. Department of Homeland Security, Strategic Intelligence
Assessment and Data on Domestic Terrorism, June 2023, pp. 25-27, https://www.fbi.gov/file-repository/fbi-dhs-
domestic-terrorism-strategic-report.pdf; Federal Bureau of Investigation and U.S. Department of Homeland
Security, Strategic Intelligence Assessment and Data on Domestic Terrorism, October 2022, pp. 20-25,
https://www.dhs.gov/sites/default/files/2022-10/22_1025_strategic-intelligence-assessment-data-domestic-
terrorism.pdf; and Federal Bureau of Investigation and U.S. Department of Homeland Security, Strategic
Intelligence Assessment and Data on Domestic Terrorism, May 2021, pp. 20-25, https://www.fbi.gov/file-repository/
fbi-dhs-domestic-terrorism-strategic-report.pdf.
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Notes: NA = not available. In the Strategic Intelligence Assessment, 2023, the FBI and DHS state that a “litany of
federal and state charges are used to charge DT subjects for applicable criminal violations.” They describe federal
charges as including “those related to weapons, explosives, threats, attacks on federal officials or facilities, hate
crimes, arson, violence against animal enterprises, and material support to terrorists.” The FBI and DHS
specifically refer to 18 U.S.C. §2339A, and state “it is a crime to provide material support or resources to
another knowing or intending they wil be used in preparation for or carrying out certain terrorism-related
offenses. Unlike a violation of 18 U.S.C. §2339B, the recipient of the material support need not be a designated
foreign terrorist organization.” See FBI and DHS, Strategic Intelligence Assessment and Data on Domestic Terrorism,
June 2023, p. 25.
a. For FY2020 to FY2022, the FBI did not break down the arrest data for federal, state, and local charges, but
instead more generally stated that arrests were often in coordination with partner agencies.
b. In FY2018, seven subjects were charged with both federal and state/local charges, and in FY2019, two
subjects were charged with both federal and state/local charges. Therefore, the number of subjects charged
federally and the number of subjects charged with state/local charges do not sum to the total number of
subjects charged for those fiscal years. For FY2020 to FY2022, the FBI provided the approximate number of
subjects. In FY2023, the FBI began referring to the subjects as “subjects included within the domestic
terrorism program.”
c. In 2019, the FBI began tagging reports of possible DT incidents to enhance program management and
operational oversight. The process is manual and user-dependent, and may not accurately capture the
number of DT referrals.
d. SLTT refers to state, local, territorial, and tribal law enforcement agencies.
e. The FBI did not provide the number of pending DT investigations for FY2015 and FY2016.
As shown in Table 1, the total number of subjects with DT-related charges decreased each year
from FY2016 to FY2019, before increasing by more than four times from 180 in FY2020 to 800
in FY2021 and then decreasing to 400 in FY2022.The increase in DT-related charges filed from
FY2020 to FY2021 is largely attributable to the DOJ investigation of the January 6, 2021, attack
on the U.S. Capitol. As of December 6, 2023, more than 1,237 defendants have been charged with
crimes related to the Capitol breach. While the FBI considers the incident itself to be DT, it is
unclear how many of these charges are considered to be DT-related.58
In recent years, the FBI and DHS have elaborated on DT-related arrests and incidents in
congressional testimony and other public statements. In 2019, FBI Director Wray informed
Congress that a majority of the DT cases that the FBI had investigated by that point in FY2019
were motivated by white supremacist violence.59 The FBI reportedly later clarified that Director
Wray meant that a majority of the DT cases involving a racial motive were thought to be
motivated by white supremacy.60 More recently, in the 2022 Strategic Intelligence Assessment
and Data on Domestic Terrorism, the FBI stated that the primary investigative classification for
DT investigations had shifted from racially or ethnically motivated violent extremism at the end
of FY2020 to anti-government or anti-authority violent extremism by the end of FY2021 (see
Table 2).

58 DOJ, U.S. Attorney’s Office, District of Columbia, 35 Months Since the Jan. 6 Attack on the Capitol.
59 U.S. Congress, Senate Committee on the Judiciary, Oversight of the Federal Bureau of Investigation, 116th Cong., 1st
sess., July 23, 2019.
60 Matt Zapotosky, “Wray says FBI has recorded about 100 domestic terrorism arrests in fiscal 2019 and many
investigations involve white supremacy,” Washington Post, July 23, 2019.
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Table 2. Percentage Breakdown of FBI DT Investigations by
Investigative Classification
FY2020 – FY2022
Investigative Classification
End of FY2020
End of FY2021
End of FY2022
Racially or Ethnically Motivated Violent Extremism
40%
19%
19%
Anti-Government or Anti-Authority Violent
37%
38%
31%
Extremism
Animal Rights/Environmental Violent Extremism
1%
1%
1%
Abortion-Related Violent Extremism
1%
0%
1%
All Other DT Threats
4%
11%
13%
Anti-Riot Laws/Civil Unresta
17%
31%
35%
Source: Federal Bureau of Investigation and U.S. Department of Homeland Security, Strategic Intelligence
Assessment and Data on Domestic Terrorism, June 2023, p. 25, https://www.fbi.gov/file-repository/fbi-dhs-domestic-
terrorism-strategic-report.pdf; and Federal Bureau of Investigation and U.S. Department of Homeland Security,
Strategic Intelligence Assessment and Data on Domestic Terrorism, October 2022, p. 20, https://www.dhs.gov/sites/
default/files/2022-10/22_1025_strategic-intelligence-assessment-data-domestic-terrorism.pdf.
Notes: In presenting these data, the FBI noted that a significant portion of the FY2021 investigations (included in
this table) were “directly related to the unlawful activities during the January 2021 siege on the U.S. Capitol” but
does not indicate the investigative classification for each investigation. The FBI provides percentages for the
investigative classifications, but does not provide all numbers.
a. In their 2023 Strategic Intelligence Assessment, the FBI added an asterisk to this category, and labeled it as a
“non-DT threat” category classification that is covered under the DT Program. In the assessment, the FBI
explains that “[a]lthough civil unrest and anti-riot investigations may not be directly aligned to the DT threat
categories, these investigations are part of the FBI’s DT Program for multiple reasons, including: because
investigation of these matters may be closely related to separate terrorism investigations; because this
criminal activity may be motivated by similar ideologies as those that appear in the DT threat categories;
and/or for other administrative or organizational matters.” See Strategic Intelligence Assessment and Data on
Domestic Terrorism, June 2023, p. 18, https://www.fbi.gov/file-repository/fbi-dhs-domestic-terrorism-
strategic-report.pdf.
Another trend highlighted by the FBI has been online radicalization of domestic extremists and
terrorist incidents related to their radicalization. Former Assistant FBI Director McGarrity noted
in testimony to Congress that radicalization to violence is increasingly taking place online where
“social media is used for the distribution of propaganda, recruitment, target selection, and
incitement to violence.”61
Former Assistant FBI Director McGarrity further explained that the global nature of the threat has
enabled extremists to engage with other like-minded individuals without having to join organized
groups. For example, a 2019 incident (highlighted by FBI Director Wray in congressional
testimony)
involved the online radicalization of a U.S. Coast Guard officer who has been accused of plotting
a domestic terrorist attack. Christopher Hasson is said to have researched online information on
Hitler, Nazis, and the number of Jewish people living in the United States, and he allegedly
plotted a large-scale terrorist attack to assassinate Democratic Members of Congress, journalists,
and others.62

61 FBI, McGarrity testimony, May 2019.
62 Lynh Bui, “‘I am dreaming of a way to kill almost every last person on earth’: A self-proclaimed white nationalist
planned a mass terrorist attack, the government says,” Washington Post, February 20, 2019; Lynn Bui, “Coast Guard
(continued...)
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Hate Crimes as Domestic Terrorism Incidents
Recent mass violence events in the United
Social Media and the DT Threat63
States and the federal response have illustrated
the conceptual overlap between DT and hate
Social media plays an important role in the
radicalization and mobilization of extremists in the
crimes. When characterizing ideologically
United States.64 Extremists of various beliefs and
inspired criminal actors for investigative
backgrounds use social media to share and consume
purposes, the FBI occasionally confronts
content; foster relationships with like-minded
suspects who can be viewed either as domestic
individuals; and, in some instances, facilitate violent
terrorists or as perpetrators of hate crimes, or
attacks. While extremists use mainstream platforms
(e.g., Facebook, X), mainstream social media
both. As noted previously, DT is not a
companies’ efforts to remove content that violates
chargeable federal offense, but hate crimes
their policies, and if necessary remove the account
are,67 and these two categories are not
responsible for the content from their platforms, may
mutually exclusive.
cause extremists to switch to less-moderated and
more encrypted social media platforms.65 In its National
Among other things, federal law defines hate
Strategy for Countering Domestic Terrorism, the Biden
crimes to include conduct involving bodily
Administration stated that DOJ is examining whether
injury in which certain jurisdictional
new legislative authorities that balance safety and the
protection of civil rights and liberties are “necessary
prerequisites are met and the offender
and appropriate.”66
intentionally selects a victim because of their
actual or perceived race, color, religion, national origin, gender, gender identity, disability, or
sexual orientation.68 Hate crimes may appear to involve ideological issues; however, as described
by one former FBI official, a hate crime “generally involve[s] acts of personal malice directed at
individuals” and is missing the broader motivations driving acts of DT.69 The line may sometimes
be blurry, and some cases may be investigated as both a hate crime and DT.
Government officials’ statements regarding certain violent incidents illustrate the challenges
officials face in characterizing acts as hate crimes or DT, or distinguishing between them. On

officer accused of plotting terrorist attack to remain jailed, judge says,” Washington Post, May 13, 2019; and Thomas
Cullen, Opinion: The Grave Threats of White Supremacy and Far-Right Extremism, DOJ, New York Times (published
February 22, 2019, by the New York Times and republished by DOJ on February 25, 2019).
63 For more information about social media and the DT threat, see CRS Insight IN11999, Law Enforcement
Investigations of Extremist Calls to Action on Social Media.
64 The National Consortium for the Study of Terrorism and Responses to Terrorism, The Use of Social Media by United
States Extremists, research brief, July 2018, https://www.start.umd.edu/pubs/
START_PIRUS_UseOfSocialMediaByUSExtremists_ResearchBrief_July2018.pdf.
65 U.S. Congress, House Committee on Energy and Commerce, Subcommittee on Communications and Technology,
Disinformation Nation: Social Media’s Role in Promoting Extremism and Misinformation, 117th Cong., 1st sess., March
25, 2021; and Ellen Nakashima, Mark Berman, and Matthew D. LaPlante, “Purges force extremists off social media
sites. That can complicate investigators’ work,” Washington Post, January 17, 2021.
66 National Strategy for Countering Domestic Terrorism, p. 25.
67 A number of federal criminal statutes expressly prohibit certain types of bias-motivated conduct. One prominent
example is the Matthew Shepard and James Byrd Jr. Hate Crimes Prevention Act of 2009 codified at 18 U.S.C. §249,
which among other things makes it a crime to “willfully cause bodily injury to any person or, through the use of ... a
dangerous weapon,” or attempt to “cause bodily injury to any person” due to certain actual or perceived characteristics
of any person. That said, a number of federal criminal statutes historically used to prosecute hate crimes do not
expressly require proof of bias nor do they specifically refer to hate crimes. For example, see 18 U.S.C. §§241, 242.
For a further overview of these statutes see CRS In Focus IF12333, Hate Crimes: Key Federal Statutes.
68 See the Matthew Shepard and James Byrd, Jr., Hate Crimes Prevention Act of 2009, 18 U.S.C. §249.
69 U.S. Congress, Senate Committee on Environment and Public Works, Eco-Terrorism Specifically Examining the
Earth Liberation Front and the Animal Liberation Front, Responses of John E. Lewis to Additional Questions from
Senator Obama, 109th Cong., 1st sess., May 18, 2005.
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May 14, 2022, Payton Gendron shot 13 individuals (who were predominantly Black; 10 were
killed) in a supermarket in Buffalo, NY.70 Prior to this incident, Gendron reportedly wrote a
document and made various online statements outlining his plans to murder Black people and
supporting a racist theory. The DOJ description of the incident, FBI Director Wray’s statement,
and President Biden’s remarks at the crime site may illustrate the challenges officials face in
characterizing acts as hate crimes, violent extremism, or DT, and distinguishing between them. In
describing the investigation, DOJ and FBI Director Wray stated they are treating the incident as a
“hate crime and an act of racially-motivated violent extremism,” while President Biden described
the incident as DT.71
While the data are not directly comparable,72 reported hate crime incidents and related federal
investigations appear to occur more frequently than reported DT incidents and their associated
investigations. As required by the Hate Crime Statistics Act (HCSA; P.L. 101-275), the FBI
collects data on hate crimes reported to the police, which are voluntarily reported by law
enforcement agencies across the country. As required by the NDAA FY2020, the FBI reports data
for “each completed or attempted incident of domestic terrorism” that has occurred in the United
States and is reported to a law enforcement agency.73 According to the FBI, reported hate crime
incidents increased 6.5%—from 10,891 in 2021 to 11,643 in 2022.74 In FY2022, the FBI reported
receiving 5,772 referrals of possible DT incidents—31.0% less than the number of referrals
(8,375) in FY2021 (see Table 1). While the NDAA FY2020 requires the FBI to report the number

70 Gendron pleaded guilty to 10 counts of first-degree murder and one count of domestic terrorism motivated by hate
(state charges). The federal case against Gendron, which includes 10 counts of hate crimes resulting in death, among
other charges, is still pending. For more information, see Bill Hutchinson and Aaron Katersky, “Judge says ‘no mercy,’
victim’s families vent their anger as Buffalo mass shooter sentenced to life,” ABC News, February 15, 2023; and DOJ,
Victim Notification – United States v. Payton Gendron, https://www.justice.gov/usao-wdny/victim-notification-united-
states-v-payton-gendron.
71 DOJ, Justice Department Statement on the Mass Shooting in Buffalo, NY, May 14, 2022; FBI, Statement on the FBI
Response to the Shooting in Buffalo, New York, May 16, 2022, https://www.fbi.gov/news/press-releases/press-
releases/statement-on-the-fbi-response-to-the-shooting-in-buffalo-new-york; and The White House, Remarks by
President Biden and First Lady Biden Honoring the Lives Lost in Buffalo, New York, and Calling on All Americans to
Condemn White Supremacy, May 17, 2022, https://www.whitehouse.gov/briefing-room/speeches-remarks/2022/05/17/
remarks-by-president-biden-and-first-lady-biden-honoring-the-lives-lost-in-buffalo-new-york-and-calling-on-all-
americans-to-condemn-white-supremacy/.
72 The FBI’s methodology for collecting and recording hate crime data is vastly different from the way it records DT
incidents. For hate crimes, the FBI collects data from law enforcement agencies across the country and requires them to
use a two-step process for investigating hate crimes before reporting them to the FBI’s Hate Crime Statistics Program.
In the first step, the law enforcement officer that initially responds to a potential hate crime incident is responsible for
determining whether there is any indication that the offense was motivated by bias against an individual’s perceived
membership in one of the groups specified in the Hate Crime Statistics Act (HCSA). If there is an indication of a bias
motivation, the incident is designated as a suspected bias-motivated crime and forwarded to an investigator. In the
second step, the investigator is responsible for reviewing the facts of the incident and making the final determination as
to whether the crime meets the HCSA definition of a hate crime. According to the FBI, an agency should only report an
incident as a hate crime when a law enforcement investigation reveals sufficient evidence to lead a reasonable and
prudent person to conclude that the offender’s actions were motivated, in whole or in part, by his or her bias. For more
information, see CRS Report R46318, Federal Data on Hate Crimes in the United States. In recording the referrals of
DT incidents or possible DT incidents, the FBI relies on its case management system (eGuardian) for handling
suspicious activity reports from federal, state, and local law enforcement agencies and the Department of Defense
related to counterterrorism, counterintelligence, cyber incidents, criminal complaints, and weapons of mass destruction.
A report is transferred to the FBI’s internal Guardian system where it is “further evaluated by the appropriate squad or
JTTF for any action deemed necessary.” See Strategic Intelligence Assessment and Data on Domestic Terrorism, 2023,
p. 27.
73 See Section 5602 of the National Defense Authorization Act for Fiscal Year 2020 (P.L. 116-92) and Strategic
Intelligence Assessment and Data on Domestic Terrorism, 2023.
74 FBI, Hate Crime Statistics, 2022, https://cde.ucr.cjis.gov.
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of FBI investigations with a nexus to DT initiated as a result of a referral or investigation by a
federal, state, local, tribal, territorial, or foreign government of a hate crime, the FBI states that it
is unable to do this because “there is no mandatory reporting requirement to identify hate crime
incidents that are also considered criminal activity that appears motivated by a political and/or
social goal consistent with the DT threat categories.”75
Political Violence and Domestic Terrorism
Some but not all political violence may be classified as DT, and it may be difficult for law enforcement to
determine the ultimate motivations in these crimes and classify them accordingly. For example, in 2017
Representative Steve Scalise and five others were shot by a DVE, but several years passed before the FBI officially
classified the incident as DT.76 In another example of the complicated nature of classifying political violence,
Secretary of Homeland Security Alejandro Mayorkas stated that the violent assault on Paul Pelosi (husband of
Speaker Nancy Pelosi) in October 2022 would be difficult to label as DT because this would have “legal
implications for particular proceedings in a court of law” and that he would “let that process play out in a court of
law.”77
Going Forward in Understanding Domestic
Terrorism: Issues Facing Congress
Congress may consider any number of legislative and oversight options in considering the federal
government’s approach in defining and confronting DT, including (1) enactment of a DT charging
statute; (2) the utility and consequences of applying the DT label in federal policy; (3) allocation
of additional, less, or equivalent appropriations to address DT; and (4) adjustments to DT data
collection requirements for federal agencies.
Considering a Federal Domestic Terrorism Charging Statute
Some observers argue in support of creating a federal criminal statute that would make DT a
chargeable federal offense under Title 18 of the U.S. Code, the main criminal code of the federal
government. Others argue against this idea.78 Overall, some believe a specific criminal statute
could help deter future terrorist attacks,79 while others believe it could alienate those who may be
sympathetic to domestic extremist causes and possibly lead to an increase in DT incidents.80

75 Strategic Intelligence Assessment and Data on Domestic Terrorism, 2023, p. 26.
76 Rebecca Beitsch, FBI Reclassifies 2017 Baseball Field Shooting as Domestic Terror, The Hill, May 17, 2021,
https://thehill.com/policy/national-security/553958-fbi-reclassifies-2017-baseball-field-shooting-as-domestic-terror/.
For the FBI’s discussion of classification of the incident as DT, see Strategic Intelligence Assessment and Data on
Domestic Terrorism, 2021, p. 35.
77 Comments by Secretary Mayorkas during interview on The Situation Room with Wolf Blitzer, CNN, October 31,
2022. See also discussion of interview in Zach Schonfeld, “Mayorkas Says its ‘Difficult’ Legally to Label Paul Pelosi
Attack ‘Domestic Terrorism’,” The Hill, October 31, 2022, https://thehill.com/policy/national-security/3713382-
mayorkas-says-its-difficult-legally-to-label-paul-pelosi-attack-domestic-terrorism/.
78 Some of these arguments are outlined in Charlie Savage, “What Could a Domestic Terrorism Law Do?,” New York
Times, August 7, 2019; and Mike Bebernes, “Does the U.S. need a domestic terrorism law to fight extremism?” Yahoo
News 360, January 16, 2021.
79 Adam Maruyama, “Terrorism is a tactic—not a color or ideology,” The Hill, January 8, 2021.
80 Emerson T. Brooking and Jacob Shapiro, “Americans Were Worried About the Wrong Threat,” The Atlantic,
January 10, 2021.
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Arguments in Support of a Domestic Terrorism Law
Arguments in support of making DT a chargeable federal offense include that (1) it would elevate
the seriousness of the crime to reflect its threat to national security, (2) it would lead to an
increase in the tools available to law enforcement to address the threat of DT and prevent future
incidents, and (3) it would lead to a more accurate understanding of the nature and scope of DT
incidents, among other arguments.81
Reflecting the Threat of Domestic Terrorism to National Security
Some argue that a chargeable DT statute would allow for DOJ to appropriately charge an
individual who has committed a DT offense with a crime to reflect an issue of national security.82
While some who commit DT-related offenses are charged with crimes that reflect national
security concerns, such as seditious conspiracy, other DT incidents do not necessarily include
charges that clearly reflect issues of national security. The FBI Agents Association83 advocates for
the creation of a DT law for this reason. In a public statement, the association argues that
“domestic terrorism is a threat to the American people and our democracy. Acts of violence
intended to intimidate civilian populations or to influence or affect government policy should be
prosecuted as domestic terrorism regardless of the ideology behind them.”84
Effect on the Tools Available to Federal Law Enforcement
Some argue that a chargeable DT statute would expand the tools available to federal law
enforcement in enforcing DT-related crimes. Proponents of a DT law have said that it would
appropriately integrate the crime into U.S. counterterrorism operations for both prevention and
response purposes. Mary McCord, former Acting Assistant Attorney General for National
Security and former Principal Deputy Assistant Attorney General for the National Security
Division, supports this argument:
It … would integrate the investigation and prosecution of all terrorism, not just
“international” terrorism, more fully into the national counterterrorism program—a
program designed to prevent terrorist attacks by aggressive use of law-enforcement tools
like online undercover personas and sting operations, and more coordinated sharing of
information between the U.S government and foreign allies and between the U.S.
government and state and local law enforcement.85
McCord points to the case of Christopher Hasson as an example of why federal prosecutors could
use more tools such as a DT law. In 2019, Hasson was arrested and accused of gathering an
arsenal and plotting to murder lawmakers and journalists in hope of inciting a race war. In 2020,

81 See, for example, Mary McCord and Jason Blazakis, “A Road Map for Congress to Address Domestic Terrorism,”
Lawfare, February 27, 2019.
82 See, for example, Thomas O’Connor, “It is time to make domestic terrorism a federal crime,” The Hill, September
13, 2017.
83 The FBI Agents Association has a membership of over 14,000 active and retired FBI special agents, and advocates
for their interests. See https://www.fbiaa.org.
84 The FBI Agents Association, FBI Agents Association Statement on Bipartisan Domestic Terrorism Legislation,
August 15, 2019, https://www.fbiaa.org/fbiaa-press-releases-list/fbi-agents-association-statement-bipartisan-domestic-
terrorism-legislation.
85 Mary B. McCord, Filling the Gaps in Our Terrorism Statutes, Program on Extremism, George Washington
University, August 2019, p. 5.
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Hasson was sentenced to over 13 years in prison for various federal firearms and drug offenses.86
McCord described the federal charges as “weak” compared to what she feels would have been a
more commensurate response—a federal charge of domestic terrorism.87
Effect on Data Collection
Some argue that a new DT law would lead to improvements in the public and lawmakers’
understanding of the nature and extent of DT through expanded data collection.88 Much of what
Congress and the public know about the DT threat stems from the FBI’s congressional testimony
and the annual Strategic Intelligence Assessment reports issued by the FBI and DHS. Research
and public understanding of DT trends and the nature of current threats may be improved by
knowing how many people have been arrested for, charged with, and convicted of DT—a
determination made in court with due process of law. (For further discussion, see the “Domestic
Terrorism Data” section.)
Arguments Against a Domestic Terrorism Law
Arguments against a DT law include that (1) it is unnecessary due to existence of other federal
laws used to target DT-related offenses, (2) it may violate the First Amendment of the
Constitution in practice, and (3) it might be used by law enforcement to unjustly target certain
groups, among other arguments.89
It Is Unnecessary As There Are Other Available Statutes
Some argue that a DT law is unnecessary because law enforcement already has the tools it needs
to arrest, prosecute, and punish those who commit or attempt to commit DT-related offenses. For
example, Christopher Hasson was prosecuted under existing federal laws and was sentenced to
more than 13 years in prison.90 Some argue that additional DT charges would be unnecessary to
further punish individuals like Hasson. One scholar argues that “[n]o ‘terrorist’ has gone
unpunished for want of a law.”91
Further, some states have DT laws, and individuals who commit DT-related offenses in those
states may face prosecution under state law. The ability of some states to prosecute individuals as
domestic terrorists, some argue, further makes the case that a federal DT statute may not be
necessary. For example, in 2023 five individuals were arrested and charged with domestic

86 United States Attorney’s Office, District of Maryland, Christopher Hasson Sentenced to More Than 13 Years in
Federal Prison on Federal Charges of Illegal Possession of Silencers, Possession of Firearms by an Addict to and
Unlawful User of a Controlled Substance, and Possession of a Controlled Substance, January 31, 2020.
87 Charlie Savage, “What Could a Domestic Terrorism Law Do?,” New York Times, August 7, 2019.
88 Mary McCord and Jason Blazakis, “A Road Map for Congress to Address Domestic Terrorism,” Lawfare, February
27, 2019.
89 See, for example, David Stebbins and Douglas Ligor, “Why labeling domestic extremists ‘terrorists’ could backfire,”
The Hill, March 1, 2021; and Moustafa Bayoumi, “No, We Do Not Need New Anti-Terrorism Laws to Combat Right-
Wing Extremists,” The Nation, January 11, 2021.
90 United States Attorney’s Office, District of Maryland, Christopher Hasson Sentenced to More Than 13 Years in
Federal Prison on Federal Charges of Illegal Possession of Silencers, Possession of Firearms by an Addict to and
Unlawful User of a Controlled Substance, and Possession of a Controlled Substance, January 31, 2020.
91 Brian Michael Jenkins, “Five Reasons to Be Wary of a New Domestic Terrorism Law,” The RAND Blog, February
24, 2021.
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terrorism as well as other crimes in Georgia for violent crimes committed at the site of the future
Atlanta Public Safety Training Center.92
It May Violate the First Amendment of the U.S. Constitution
Some argue that a new DT law may encroach on free speech protected by the First Amendment of
the Constitution.93 There is concern that law enforcement would unlawfully investigate the
activity of individuals and groups that adhere to certain ideologies. The FBI has repeatedly
expressed that it is careful not to encroach on First Amendment protected activity, but it has been
clear that it does “not tolerate violent agitators and extremists who use the guise of First
Amendment-protected activity to incite violence and wreak havoc.”94 It is a delicate balance for
the FBI even without a chargeable DT statute. For example, the FBI field office in Norfolk, VA,
issued a situational information report that warned of violence at the U.S. Capitol on January 6,
2021; the FBI discovered the threat through statements made on an online message board. Even
with the threat of violence, the FBI expressed concern over First Amendment protected speech in
its report (as obtained by and quoted in the Washington Post):
“Individuals/Organizations named in this [situational information report] have been
identified as participating in activities that are protected by the First Amendment to the
U.S. Constitution,” the document says. “Their inclusion here is not intended to associate
the protected activity with criminality or a threat to national security, or to infer that such
protected activity itself violates federal law.… However,” it continues, “based on known
intelligence and/or specific historical observations, it is possible the protected activity
could invite a violent reaction towards the subject individual or others in retaliation or with
the goal of stopping the protected activity from occurring in the first instance. In the event
no violent reaction occurs, FBI policy and federal law dictates that no further record be
made of the protected activity.”95
Regardless of support for a DT law, some have expressed further the First Amendment-related
concern that enforcement of a DT law would lead to the unlawful targeting of the protected
activity of certain groups depending on the balance of political power at the time.96
Enforcement Might Unjustly Target Certain Groups
Some individuals who oppose a DT law have looked to the past to point out how enforcement of
such a law might be used to unjustly target certain groups based on any number of factors
including race, ethnicity, and political beliefs. Examples provided include the federal
government’s use of the Alien Registration Act of 1940 (also known as the Smith Act) to
allegedly target communists during the so-called Red Scare97 and currently existing terrorism
authorities to allegedly target Black civil rights activists, individuals from Muslim, Arab, Middle
Eastern, and South Asian communities, animal rights and environmental rights activists, and

92 Georgia Bureau of Investigation, Five Arrested for Domestic Terrorism Charges at Site of Future Atlanta Public
Safety Training Center, June 23, 2023, https://gbi.georgia.gov/press-releases/2023-06-23/five-arrested-domestic-
terrorism-charges-site-future-atlanta-public.
93 For legal discussion of the Free Speech Clause of the First Amendment, see CRS In Focus IF11072, The First
Amendment: Categories of Speech.
94 FBI, Director Wray’s Statement on Violent Activity at the U.S. Capitol Building, January 7, 2021.
95 The FBI field office in Norfolk, VA, as quoted in Devlin Barrett and Matt Zapotosky, “FBI report warned of ‘war’ at
Capitol, contradicting claims there was no indication of looming violence,” Washington Post, January 12, 2021.
96 Richard B. Zabel, “Domestic terrorism is a national problem. It should also be a federal crime,” Washington Post,
February 2, 2021.
97 Ibid.
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members of other groups viewed as having controversial beliefs.98 In another example, a former
FBI agent and Brennan Center fellow claimed the FBI wrongly identified eco-terrorism as the top
terrorist threat in the United States from 2004-2008.99 Some who argue against a DT law claim
that a new authority would be used in similar discriminatory ways.
Utility of Using the Domestic Terrorism Term
If individuals who commit DT-related offenses cannot be charged with DT, some observers may
question the utility of federal law enforcement labeling threats, incidents, and investigations as
DT and referring to individuals as domestic terrorists. Congress may consider how the DT label is
applied and how the term domestic terrorism is used in federal law enforcement activities (and
the consequences of applying the term) and data collection.
Understanding the Threat and the Data
Labeling individuals who have committed an act of DT according to the category of extremism
they adhere to helps lawmakers, law enforcement agencies, and researchers understand the nature
and extent of the DT threat and how to address it. Congress may consider whether to direct the
FBI and DHS regarding the manner in which they categorize and label DT threats. There remains
some confusion as to how the FBI and DHS establish DT threat categories and how or why some
categories may be added or removed.
The labeling and recognition of extremist beliefs as a way to describe and categorize the DT
threat as well as the labeling of certain crimes as DT or groups as domestic terrorist groups have
caused controversy among the public and lawmakers.100 Even when an incident precisely fits the
definitions of DT provided in statute, the use of DT as a label for the incident and the perpetrators
can be controversial. Congress may consider whether revising DT statutes should include further
detail as to what qualifies as DT and whether the responsibility of labeling incidents as DT and
individuals as domestic terrorists belongs with government agencies or with judges and juries.
Consequences of Being Labeled a Domestic Terrorist
If the FBI or other federal agency conclude that an individual’s actions (or suspected actions)
qualify as DT, then that individual could be added to the FBI’s Threat Screening System
(formerly known as the Terrorist Screening Database and commonly known as the Terrorist
Watchlist.) The Terrorist Watchlist is the U.S. government’s consolidated database containing
sensitive (but unclassified) law enforcement and national security information regarding those
who are known to be or are reasonably suspected of being involved in terrorist activities (both
domestic and international). Portions of the Watchlist are exported to data systems in federal
agencies that perform screening activities. These data systems101 include the No Fly, Selectee, and

98 American Civil Liberties Union, Written Statement of the Record, American Civil Liberties Union, Written Statement
submitted to the U.S. Senate Committee on Homeland Security and Governmental Affairs for the hearing entitled,
Countering Domestic Terrorism: Examining the Evolving Threat on September 25, 2019, pp. 3-4,
https://www.aclu.org/hearing-statement/aclu-written-statement-record-emerging-domestic-terrorism-threat.
99 Michael German, “Why New Laws Aren’t Needed to Take Domestic Terrorism More Seriously,” Brennan Center
for Justice, December 14, 2018.
100 Michael Murray, “CPAC Dallas panel proclaims ‘We are all domestic terrorists’,” Chron, August 8, 2022,
https://www.chron.com/politics/article/CPAC-Dallas-we-are-all-domestic-terrorists-banner-17359959.php; Charlie
Savage, “Was the Jan. 6 Attack on the Capitol an Act of ‘Terrorism’?,” New York Times, January 7, 2022; and Betsy
Woodruff Swan, “Trump says he’s naming antifa a ‘Terrorist Organization.’ Can he do that?”, Politico, May 31, 2020.
101 For a brief discussion of such databases, see the “Exporting of Information” section of this CRS report.
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Expanded Selectee lists for airline passenger screening.102 Watchlist information is also used by
select foreign governments for screening purposes and to assist in coordination of terrorist threat
awareness, assessment, analysis, or response. Watchlist data are also shared with certain private
entities (both domestic and foreign) for the same purposes.103
Congress may wish to review the federal government’s existing authorities that allow the FBI to
include known or suspected domestic terrorists on the Watchlist.104
Addressing the Threat
Understanding the nature and extent of the DT threat may help Congress and federal agencies
effectively allocate resources to secure the homeland. For example, in congressional testimony,
FBI Director Wray has highlighted the evolving DT threat and said the FBI was dealing with
“lone domestic violent extremists radicalized by personalized grievances ranging from racial and
ethnic bias to anti-government, anti-authority sentiment to conspiracy theories.”105 Wray went on
to explain this was why the FBI was dedicating more resources to DT investigations.
Allocation of Resources to Address Domestic Terrorism
Until recently, federal agencies, such as DHS and the FBI, did not specifically address the DT
threat in their budgets. Instead, these agencies used existing funding streams to address the DT
threat. For example, the FBI generally handled DT as part of its overall counterterrorism program
and did not seem to dedicate specific resources to countering DT. Today, federal agencies
describe the nature and extent of DT threats in their budget requests to Congress and allocate
resources according to these threats, including the following examples:
• In 2021, DOJ began to summarize its budgetary requests specific to DT for the
next fiscal year.106 DOJ also emphasized the need for additional resources due to
the increasing number of cases and defendants related to the January 6, 2021,
attack on the U.S. Capitol.107
• In a FY2022 congressional budget hearing, DHS Secretary Mayorkas stated that
DT is “the most lethal and persistent terrorism-related threat to the United States
today,” and explained that this was the reason for DHS requesting “$131 million
to support innovative methods to prevent domestic terrorism while respecting
privacy, civil rights, and civil liberties.”108

102 DOJ, Office of Inspector General, “Audit of the Federal Bureau of Investigation’s Management of Terrorist
Watchlist Nominations,” March 2014, footnote 10, p. 4. For broader discussion of this issue, see CRS In Focus
IF11731, Aviation Security Measures and Domestic Terrorism Threats.
103 FBI, “Terrorist Screening Records System (TSRS),” 72 Federal Register 47073, August 22, 2007; FBI, Terrorist
Screening Center, “Frequently Asked Questions,” https://ucr.fbi.gov/nsb/tsc/terrorist-screening-center-frequently-
asked-questions-032416.pdf; and FBI, Terrorist Screening Center, https://www.fbi.gov/investigate/terrorism/tsc.
104 For a legal discussion of the issues surrounding the Terrorist Watchlist, see CRS Legal Sidebar LSB11009, Legal
Challenges to the Terrorist Screening Database.
105 Christopher Wray, Threats to the Homeland: Evaluating the Landscape 20 Years After 9/11, Federal Bureau of
Investigation, Statement Before the Senate Homeland Security and Governmental Affairs Committee, September 21,
2021.
106 See DOJ, FY2022 Budget Request: Addressing Domestic Terrorism, fact sheet.
107 Ibid.
108 Secretary Alejandro Mayorkas, Secretary Alejandro N. Mayorkas Testimony to the Senate Homeland Security and
Governmental Affairs Committee, DHS, July 27, 2021.
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• For FY2024, the FBI requested a budget increase “to counter the increasing acts
of domestic terrorism across the United States.”109
Similarly, until recently Congress did not specifically address the DT threat in appropriations.
Today, Congress specifically appropriates resources to address the DT threat, including the
following examples:
• In FY2022, Congress appropriated additional resources for the FBI to counter DT
and required the FBI to provide (in future expenditure plans) details on DT
threats and the resources to address them.110 Further, Congress directed the FBI
“to provide the Committees on Appropriations with terrorism threat category
descriptions and assessments as part of the normal budget review process, as well
as when requested or as new threat scenarios develop, to ensure the Committees
have the necessary insight into the alignment of threats and resource
allocation.”111
• In FY2022, Congress directed DHS to coordinate with DOJ and the FBI to
promote information sharing and a collaborative effort to combat DT.112
• In FY2023, Congress made similar provisions for DOJ and DHS to address
DT.113
Congress may consider various options when addressing the DT threat through allocation of
resources. It may choose to rely on a broader strategy (such as that outlined in the National
Strategy for Countering Domestic Terrorism) and appropriate funds according to the strategy, and
possibly across a broader range of federal agencies. Alternatively, policymakers could choose to
reduce the scope of DT resources allocated (e.g., request fewer resources be dedicated to the
issue) and/or remove references to DT from appropriations language and other legislative
direction. Through appropriations law, Congress may also request more data and transparency
from agencies that address DT and collect additional data to more fully understand the DT threat.
Domestic Terrorism Data
Domestic terrorists have orchestrated numerous attacks over the last several decades, and
collective knowledge of these incidents is more limited than knowledge of crime more generally.
There are several reasons for this. First, unlike other federal crimes, the federal government does

109 DOJ, Statement of Christopher A. Wray, Director, Federal Bureau of Investigation Before the Subcommittee on
Commerce, Justice, Science and Related Agencies, Committee on Appropriations, United States House of
Representatives at a Hearing Entitled “Federal Bureau of Investigation Budget Request for Fiscal Year 2024, April 27,
2023.
110 U.S. Congress, House Committee on Appropriations, Consolidated Appropriations Act, 2022 (H.R. 2471; P.L. 117-
103): Provisions Applying to All Divisions of the Consolidated Appropriations Act, committee print, 117th Cong., 1st
sess., pp. 257-258.
111 Ibid., p. 258.
112 Ibid., p. 1207.
113 See U.S. Congress, House Committee on Appropriations, Subcommittee on Commerce, Justice, Science, and
Related Agencies, Commerce, Justice, Science, and Related Agencies Appropriations Bill, 2023, H.Rept. 117-395, To
accompany H.R. 8256, 117th Cong., 2nd sess., p. 57; and U.S. Congress, House Committee on Appropriations,
Subcommittee on Homeland Security, Department of Homeland Security Appropriations Bill, 2023, H.Rept. 117-396,
To accompany H.R. 8257, 117th Cong., 2nd sess., p. 7.
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not publish annual data on DT-related prosecutions and sentencing.114 For example, the public can
find the number of defendants prosecuted in federal court for drug offenses in recent years
through the Bureau of Justice Statistics, Federal Justice Statistics Program,115 but the public
cannot do the same for DT offenses. Part of the reason for this is the absence of a federal DT
charging statute. However, as required by the NDAA 2020, the FBI now provides data on the
“number of federal charges with a DT nexus” (see Table 1), but the data are still not as robust as
those for other federal crime categories. For example, the U.S. Sentencing Commission does not
identify sentencing outcomes for convictions related to DT but rather the specific federal statutes
that were violated and the associated sentence. Congress could consider placing additional
reporting requirements on other federal agencies such as the U.S. Sentencing Commission.
Another reason that knowledge of DT incidents and threats is limited is because federal agencies
label some of these data as For Official Use Only. For example, in August 2022 I&A at DHS
released data on DVE attacks and disrupted plots in the United States from 2010-2021, but
released it as For Official Use Only. If broader disclosure is sought, Congress could require that
additional DT data be released to the public, and consider conducting oversight of the internal
processes of classifying data as For Official Use Only and other processes such as classifying
information as Law Enforcement Sensitive.
While the NDAA FY2020 required the FBI and DHS to report DT data, there is no mandatory
incident reporting requirement for DT incidents to be reported to the federal government. As the
Strategic Intelligence Assessment, 2022, notes, “many DT incidents are rooted in state and local
level criminal activity,”116 and a complete understanding of the prevalence of DT in the United
States is not possible without state and local DT incident data. Congress could consider
encouraging states and localities to report DT incident data by incentivizing states, if necessary, to
report these data through vehicles such as grant conditions.
Finally, the NDAA FY2020 required the Strategic Intelligence Assessment reports to be updated
annually for five years. Should Congress decide to continue to require the FBI and DHS to
publish these reports, it could renew this requirement in subsequent legislation and ask for
additional DT data and information from these agencies.

Author Information

Lisa N. Sacco

Analyst in Illicit Drugs and Crime Policy

114 The U.S. Sentencing Commission publishes the number of federal offenders receiving terrorism-related sentencing
guidelines adjustments (§3A1.4) but does not indicate whether it is international or domestic terrorism. See U.S.
Sentencing Commission, 2022 Annual Report and Sourcebook of Federal Sentencing Statistics, https://www.ussc.gov/
research/sourcebook-2022.
115 See DOJ, Federal Criminal Case Processing Statistics.
116 Strategic Intelligence Assessment and Data on Domestic Terrorism, 2022, p. 20.
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