Terrorist Material Support: An Overview of 18 U.S.C. § 2339A and § 2339B

Terrorist Material Support: An Overview of
August 15, 2023
18 U.S.C. § 2339A and § 2339B
Charles Doyle
The material support statutes, 18 U.S.C. § 2339A and § 2339B, have been among the
Senior Specialist in
most frequently prosecuted federal anti-terrorism statutes. Section 2339A outlaws:
American Public Law


(1) whoever

(2) [knowingly]
(3)(a) attempting to,
(b) conspiring to, or
(c) actually
(4)(a) providing material support or resources, or
(b) concealing or disguising
(i) the nature,
(ii) location,
(iii) source, or
(iv) ownership of material support or resources
(5) knowing or intending that they be used
(a) in preparation for,
(b) in carrying out,
(c) in preparation for concealment of an escape from, or
(d) in carrying out the concealment of an escape from
(6) an offense identified as a federal crime of terrorism.

Section 2339B outlaws:
(1) whoever
(2) knowingly
(3)(a) attempting to provide,
(b) conspiring to provide, or
(c) actually providing
(4) material support or resources
(5) to a foreign terrorist organization
(6) knowing that the organization
(a) has been designated a foreign terrorist organization, or
(b) engages, or has engaged, in “terrorism” or “terrorist activity.”

The sections each define the term “material support or resources” to mean any service or tangible or intangible
property. The Supreme Court in Humanitarian Law Project upheld § 2339B, as applied, against challenges that it
was unconstitutionally vague and inconsistent with the First Amendment’s freedom of speech and freedom of
association requirements. Violations of § 2339A are punishable by imprisonment for not more than 15 years;
violations of § 2339B by imprisonment for not more than 20 years. Although the sections do not create a civil
cause of action for victims, treble damages and attorneys’ fees may be available for some victims under 18 U.S.C.
§ 2333, which Congress clarified in 2016 to expressly extend to anyone who aids and abets the victimizing
commission of an act of international terrorism.
Section 2339B has two extraterritorial jurisdiction provisions. One is general, providing for extraterritorial jurisdiction over
an offense (“there is extraterritorial jurisdiction over an offense under this section”), and the other enumerates categories in
which extraterritorial jurisdiction is provided (for example, the offender is a U.S. national). Section 2339A has no such
provisions, but it likely applies overseas at least when its predicate offense or offenses have extraterritorial reach.
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Contents
Introduction ..................................................................................................................................... 1
Background ..................................................................................................................................... 1
Support of Terrorism (18 U.S.C. § 2339A) ..................................................................................... 2
Whoever .................................................................................................................................... 3
Knowingly ................................................................................................................................. 4
Provides ..................................................................................................................................... 5
Concealing or Disguising Material Support .............................................................................. 5
Material Support........................................................................................................................ 6
Use in Relation to a Federal Crime of Terrorism ...................................................................... 7
Attempt, Conspiracy, Aiding and Abetting ............................................................................... 8
Consequences of Charge or Conviction .................................................................................. 10
Federal Crime of Terrorism ............................................................................................... 10
Extraterritorial Jurisdiction ...................................................................................................... 11
Venue ....................................................................................................................................... 12
Defenses .................................................................................................................................. 13
Civil Actions............................................................................................................................ 13

Support of Designated Terrorist Organizations (18 U.S.C. § 2339B) ........................................... 16
Whoever .................................................................................................................................. 17
Knowingly ............................................................................................................................... 17
Provides ................................................................................................................................... 18
Material Support...................................................................................................................... 18
Terrorist Organizations ............................................................................................................ 20
Designated Terrorist Organizations ................................................................................... 21
Attempt, Conspiracy, Aiding and Abetting ............................................................................. 22
Consequences of Charge or Conviction .................................................................................. 24
Federal Crime of Terrorism ............................................................................................... 26
Extraterritorial Jurisdiction ..................................................................................................... 27
Civil Actions............................................................................................................................ 28
Reporting Requirements ................................................................................................... 30
Protection of Classified Information ................................................................................. 30


Contacts
Author Information ........................................................................................................................ 32

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Terrorist Material Support: An Overview of 18 U.S.C. § 2339A and § 2339B

Introduction
Two federal material support statutes sit at the heart of the Justice Department’s terrorist
prosecution efforts.1 One provision, 18 U.S.C. § 2339A, outlaws providing material support for
the commission of certain designated offenses that might be committed by terrorists. The other,
18 U.S.C. § 2339B, outlaws providing material support to certain designated terrorist
organizations. They share a common definition of the term “material support,” augmented to
some extent in § 2339B cases. 2
Background
Since their inception in the mid-1990s, Congress has periodically expanded and sought to clarify
the scope of § 2339A and § 2339B. Section 2339A passed with little fanfare as part of a wide-
ranging crime package, the Violent Crime Control and Law Enforcement Act of 1994.3 Almost
immediately, Congress amended § 2339A and supplemented it with § 2339B as part of the
Antiterrorism and Effective Death Penalty Act of 1996 (AEDPA).4 As the House committee
report explained, § 2339B reflected a recognition of
the fungibility of financial resources and other types of material support. Allowing an
individual to supply funds, goods, or services to an organization, or to any of its subgroups,

1This report is available in an abridged version as CRS Report R41334, Terrorist Material Support: A Sketch of 18
U.S.C. § 2339A and § 2339B
, without the footnotes, citations to authority, attributions, or attachments found here.
2 A Review of the Material Support to Terrorism Prohibition Improvements Act: Hearing Before the Subcomm. on
Terrorism, Technology and Homeland Security
, 109th Cong., 1st Sess. 45 (2005) (statement of Barry Sabin, Chief,
Counterterrorism Section, U.S. Dept. of Justice); Implementation of the USA PATRIOT Act: Prohibition of Material
Support Under Sections 805 of the USA PATRIOT Act and 6603 of the Intelligence Reform and Terrorism Prevention
Act of 2004
, 109th Cong., 1st Sess. 18 (2005) (statement of Barry Sabin, Chief, Counterterrorism Section, U.S. Dept. of
Justice); David Cole, Out of the Shadows: Preventive Detention, Suspected Terrorists, and War, 97 CAL. L. REV. 693,
723 (2009) (“The most important of these statutes is 18 U.S.C. § 2339B . . . . [R]arely enforced before 9/11, it has since
become a principal tool in the Justice Department’s ‘terrorism’ prosecutions.”); Francesca Laguardia, Considering a
Domestic Terrorism Statute and Its Alternatives
, 114 NW. U. L. REV. 1061, 1071 (2020); (“[M]ost ‘terrorism
prosecutions’ are material support prosecutions under § 2339B. Exemplifying this point, the Center on National
Security has found that over 66% of ISIS prosecutions have been § 2339B prosecutions.”); Shirin Sinnar, Separate and
Unequal: The Law of Domestic and International Terrorism
, 117 MICH. L. REV. 1333, 1356 (2019) (“Indeed, attempt
or conspiracy to provide material support are exceedingly common charges in international terrorism cases.”).
3 Pub. L. No. 103-322, § 120005, 108 STAT. 2022 (1994). The Violent Crime Control and Law Enforcement Act was a
355-page amalgam of legislative proposals consisting of 33 separate titles which included Cop on the Beat grants, the
Violence Against Women Act, revival of the death penalty as a federal sentencing alternative, a ban on assault
weapons, DNA identification, and crime victims’ rights. Its various components were the subject of two dozen House
committee reports, listed in 1994 U.S.C.C.A.N. 1801 (1994), none which appear to have addressed § 2339A. The
section, however, was included in much the same language in separate legislative proposals offered by members of
both parties in both Houses during the 103d Congress, see e.g., H.R. 1301, 103rd Cong. § 110 (Representative
Schumer); H.R. 2807, 103rd Cong. § 702 (Representative Sensenbrenner); H.R. 2872, 103rd Cong. § 421 103rd Cong.
(Representative McCullom); H.R. 3131, 103rd Cong. (Representative Brooks); S. 8, 103rd Cong. § 702 (Senator
Hatch); S. 1488, 103rd Cong. § 726 (Senator Biden).
4 Pub. L. No. 104-132, §§ 323, 303, 110 STAT. 1255, 1250, respectively. Section 323 amended § 2339A to enlarged its
predicate offense list to include 18 U.S.C. §§ 37 (relating to violence at international airports), 81 (relating to arson),
175 (relating to biological weapons), 831 (relating to nuclear weapons), 842(m) and (n) (relating to plastic explosives),
1362 (relating to destruction of communications facilities), 2155 and 2156 (relating to destruction, or defective
production, of war materials), 2332 (relating to terrorist violence against Americans overseas), 2332a (relating to
weapons of mass destruction), and 2332b (multi-national terrorism). Later in the year, Congress added three other
crimes to § 2339A’s predicate offense list: 18 U.S.C. §§ 930(c) (relating to use of a firearm during a murderous attack
on a federal facility), 1992 (relating to train wrecking), and 2332c (relating to chemical weapons). Economic Espionage
Act of 1996, Pub. L. No. 104-294, § 601(b)(2), (s)(2), (s)(3), 110 STAT. 3502, 3506 (1996).
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Terrorist Material Support: An Overview of 18 U.S.C. § 2339A and § 2339B

that draw significant funding from the main organization’s treasury, helps defray the costs
to the terrorist organization of running the ostensibly legitimate activities. This in turn frees
an equal sum that can then be spent on terrorist activities.5
In 2001, the USA PATRIOT Act amended both sections, (1) increasing the maximum term of
imprisonment from 10 to 15 years (and to life imprisonment when commission of the offense
resulted in death); (2) adding “expert advice or assistance” to forms of proscribed material
support or resources; and (3) subjecting attempts and conspiracies to violate § 2339A to the same
maximum penalties as the substantive violation of the section.6
The Intelligence Reform and Terrorism Prevention Act of 2004 amended the definition of
“material support or resources” that applies to both sections.7 The specific forms of support
previously used to define the term became examples in a more general definition which covers
“any property, tangible or intangible, or service.”8 Congress added clarifying definitions for
“training” and “expert advice or assistance,” and a clarifying explanation of the term “personnel”
in § 2339B. At the same time, the predicate offense list of § 2339A expanded to cover any of the
federal crimes of terrorism.9
In 2009, Congress added genocide and recruiting child soldiers to § 2339A’s predicate offense
list10 and adjusted § 2339B’s deadlines for the government’s interlocutory appeals relating to
classified information.11 In 2015, it increased the maximum penalty for violating § 2339B from
imprisonment for not more than 15 years to imprisonment for not more than 20 years.12
In 2016, Congress amended § 2333 to make it clear that civil liability for international terrorist
offenses extends to those who aid and abet the commission of those offenses.13 Congress further
amended § 2333 in 2018 to permit the use of certain blocked assets to satisfy judgments of U.S.
nationals secured against a “terrorist party.”14
Support of Terrorism (18 U.S.C. § 2339A)
Section 2339A outlaws support or concealing support for the crimes a terrorist has committed or
may be planning to commit. More precisely, § 2339A provides:
(1) whoever

5 H.R. REP. NO.104-383, 81 (1995). AEDPA also eliminated a restriction on § 2339A investigations which the report
characterized as “effectively negat[ing] the efficacy of § 2339A.” Id. at 82.
6 Pub. L. No. 107-56, §§ 805(a), 810(c), (d), 811, 115 STAT. 377, 380, 381 (2001). At the time, attempts and
conspiracies to violate § 2339B were already subject to the same maximum penalty as the underlying substantive
offense, 18 U.S.C. § 2339B (2000).
7 Pub. L. No. 108-458, § 6603, 118 STAT. 3762 (codified at 18 U.S.C. § 2339B(g)(4) (2006)). The amendments,
initially temporary, were made permanent in the USA PATRIOT Act Improvement and Reauthorization Act of 2005,
Pub. L. No. 109-177, § 104, 120 STAT. 195 (2006).
8 18 U.S.C. § 2339A(b)(1).
9 Id. § 2339A(a).
10 Human Rights Enforcement Act of 2009, Pub. L. No. 111-122, § 3(d), 123 STAT. 3481-82 (codified at 18 U.S.C.
§ 2339A(a)).
11 Statutory Time-Periods Technical Amendments Act of 2009, Pub. L. No. 111-16, §§ 3(6), (3)7, 3(8), 123 STAT. 1608
(codified at 18 U.S.C. § 2339B(f)(5)(B)(ii), (f)(5)(B)(iii)(I), (f)(5)(B)(iii)(III)).
12 USA FREEDOM Act of 2015, Pub. L. No. 114-23, tit. VI, §704, 129 STAT. 300.
13 Justice Against Sponsors of Terrorism Act, Pub. L. No. 114-222, § 4, 133 STAT. 852 (2016) (codified at 18 U.S.C.
§ 2333(d)).
14 Anti-Terrorism Clarification Act of 2018, Pub. L. No. 115-253, 132 STAT. 3182 (codified at 18 U.S.C. § 2333(e)).
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Terrorist Material Support: An Overview of 18 U.S.C. § 2339A and § 2339B

(2) [knowingly]
(3)(a) attempts to,
(b) conspires to, or
(c) actually
(4)(a) provides material support or resources, or
(b) conceals or disguises
i. the nature,
ii. location,
iii. source, or
iv. ownership
of material support or resources
(5) knowing or intending that they be used
(a) in preparation for,
(b) in carrying out,
(c) in preparation for concealment of an escape from, or
(d) in carrying out the concealment of an escape from
(5) an offense identified as a federal crime of terrorism.15
Whoever
“Whoever” usually means any legal entity or individual. The Dictionary Act declares that “In
determining the meaning of any Act of Congress, unless the context indicates otherwise . . . the
words ‘person’ and ‘whoever’ include corporations, companies, associations, firms, partnerships,
societies, and joint stock companies, as well as individuals.”16 Elsewhere, courts have looked to
the Dictionary Act when construing a federal criminal statute.17 Moreover, federal law now
generally holds that corporations are criminally liable for crimes committed by their officers,
employees, or agents within the scope of their employment and for the benefit of the
corporation,18 although at common law corporations could not be held criminally liable.19

15 More exactly, § 2339A(a) declares, “Whoever provides material support or resources or conceals or disguises the
nature, location, source, or ownership of material support or resources, knowing or intending that they are to be used in
preparation for, or in carrying out, a violation of section 32, 37, 81, 175, 229, 351, 831, 842(m) or (n), 844(f) or (i),
930(c), 956, 1091, 1114, 1116, 1203, 1361, 1362, 1363, 1366, 1751, 1992, 2155, 2156, 2280, 2281, 2332, 2332a,
2332b, 2332f, 2340A, or 2442 of this title, section 236 of the Atomic Energy Act of 1954 (42 U.S.C. 2284), section
46502 or 60123(b) of Title 49, or any offense listed in section 2332b(g)(5)(B) (except for sections 2339A and 2339B)
or in preparation for, or in carrying out, the concealment of an escape from the commission of any such violation, or
attempts or conspires to do such an act, shall be fined under this title, imprisoned not more than 15 years, or both, and,
if the death of any person results, shall be imprisoned for any term of years or for life. . . . ”.
Here and elsewhere “knowingly” has been added to the section’s elements to reflect the requirement that aid be given
“knowing or intending” that it will be used in connection with a terrorist predicate offense.
16 1 U.S.C. § 1.
17 E.g., United States v. A & P Trucking Co., 358 U.S. 121, 123 (1958); United States v. Polizzi, 500 F.2d 856, 907
(9th Cir. 1974); United States v. George, 946 F.3d 643, 647 (4th Cir. 2020) (“Congress drafted the identity theft statutes
using the term ‘person,’ which the Dictionary Act defines as . . . ”); United States v. Ruzicka, 331 F. Supp. 3d 888, 893
n.2 (D. Minn. 2018) (“While the CVRA [Crime Victims’ Rights Act] does not define ‘person,’ the Dictionary Act
defines ‘person’ to include both individuals and corporations.”).
18 United States v. Grayson Enters., 950 F.3d 386, 407–08 (7th Cir. 2020); United States v. Agosto-Vega, 617 F.3d
541, 552–53 (1st Cir. 2010); United States v. Singh, 518 F.3d 236, 249–50 (4th Cir. 2008); see generally CRS Report
R43293, Corporate Criminal Liability: An Overview of Federal Law, by Charles Doyle.
19 I WILLIAM BLACKSTONE, COMMENTARIES ON THE LAWS OF ENGLAND 464 (1765) (“A corporation cannot commit
treason, or felony, or other crime, in its corporate capacity: though its members may, in their distinct individual
capacities.”) (transliteration provided).
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Terrorist Material Support: An Overview of 18 U.S.C. § 2339A and § 2339B

Knowingly
At common law, every crime consisted of two essentials, one mental (mens rea) and the other
physical (actus reus).20 As Justice Jackson explained, “[c]rime, as a compound concept, generally
constituted only from the concurrence of an evil-meaning mind with an evil-doing hand.”21 Later,
legislative bodies, Congress included, from time to time created criminal offenses which had no
mental component, no mens rea.22 This type of strict liability occurred most often for regulatory,
“public welfare” misconduct, misconduct that did not constitute a common law crime.23 These
offenses ordinarily carried fines or short periods of incarceration.24 Courts and commentators
came to associate the lack of a mens rea with less severely punished offenses.25
The Supreme Court has stopped short of equating felony status with the intent to require a mens
rea component. In Staples, however, it declared that where “dispensing with mens rea would
require the defendant to have knowledge only of traditionally lawful conduct, a severe penalty is
a further factor tending to suggest that Congress did not intend to eliminate a mens rea
requirement. In such a case, the usual presumption that a defendant must know the facts that
make his conduct illegal should apply.”26
Section 2339A speaks to “whoever provides” material support. Unlike § 2339B, it does not say
“whoever knowingly provides” material support. Thus, on its face, it might be thought to envelop
both those who knowingly provide support and those who unknowingly or inadvertently provide
support. Yet Staples suggests that the courts will reject such an interpretation without a clear
congressional contrary intent. Section 2339A offenses are 15-year felonies. Considered alone, this
penalty length seems to weigh heavily on the implied mens rea side of the ledger. The nature of
the support provided might suggest a more mixed result. Some of the support, like providing
lodging or training, is a form of “traditionally lawful conduct.” Some, like providing false
documentation, is not. The most telling indication of Congress’s intent, however, appears later in
the section where Congress has supplied an explicit mens rea requirement. Providing support only

Mens Rea, BLACK’S LAW DICTIONARY 1181 (11th ed. 2019) (“[Law Latin ‘guilty mind’] The state of mind that the
prosecution, to secure a conviction, must prove that a defendant had when committing a crime . . .. Mens rea is the
second of two essential elements of every crime at common law, the other being actus reus.”); see generally CRS
Report R46836, Mens Rea: An Overview of State-of-Mind Requirements for Federal Criminal Offenses, by Michael A.
Foster.
21 Morissette v. United States, 342 U.S. 246, 251 (1952) (“Crime, as a compound concept, generally constituted only
from the concurrence of an evil-meaning mind with an evil-doing hand . . . .”).
22 Id. at 253–60.
23 Id. at 255; Staples v. United States, 511 U.S. 600, 616–17 (1994).
24 Staples, 511 U.S. at 616 (“Certainly, the cases that first defined the concept of the public welfare offense almost
uniformly involved statutes that provided for only light penalties such as fines or short jail sentences, not imprisonment
in the state penitentiary.”).
25 Id. at 616–17 (“As commentators have pointed out, the small penalties attached to such offenses logically
complemented the absence of a mens rea requirement: In a system that generally requires a ‘vicious will’ to establish a
crime, imposing severe punishments for offenses that require no mens rea would seem incongruous. Indeed, some
courts justified the absence of mens rea in part on the basis that the offenses did not bear the same punishments an
‘infamous crimes,’ and questioned whether imprisonment was compatible with the reduced capability required or such
regulatory offenses. Similarly, commentators collecting the early cases have argued that offenses punishable by
imprisonment cannot be understood to be public welfare offenses . . . .” (quoting Staples v. United States, 511 U.S.
600, 608 n.3 (1994))
26 Id. at 618–19 (emphasis added); see also United States v. Farah, 766 F.3d 599, 613 (6th Cir. 2014) (“Where a statute
is silent as to the mens rea requirement, the appropriate standard is whether the act is done ‘knowingly’”); Elonis v.
United States, 575 U.S. 723, 735 (2015) (“[O]ur cases have explained that a defendant generally must ‘know the facts
that make his conduct fit the definition of the offense.’” (quoting Staples v. United States, 511 U.S. 600, 608 n.3
(1994)).
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Terrorist Material Support: An Overview of 18 U.S.C. § 2339A and § 2339B

violates the section if it is provided “knowing or intending” that the support will be used to
commit or prepare for the commission of a predicate offense. A defendant cannot unknowingly
provide support or resources while at the same time “know[] or intend[] that they are to be used”
for the commission of one of the predicate offenses.
As general rule, a “knowing” mens rea standard requires the government to prove that the
defendant had “knowledge of the facts that constitute the offense.”27 The government need not
prove that the defendant knew his conduct was unlawful.28
Provides
Little is said of the meaning of the word “provides” in § 2339A or § 2339B. When a statute’s text,
its context, or its legislative history suggest otherwise, Congress is thought to have intended
common words to have their common meaning.29 The word “provide” ordinarily means “to
supply something for sustenance or support.”30 Section 2339A has no explicit definition of the
word “provide.” At least two lower federal courts have suggested that the word “provide” in §
2339A should be given its ordinary dictionary meaning.31 The section immediately following §§
2339A and 2339B states that “the term ‘provides’ includes giving, donating, and transmitting.”32
Concealing or Disguising Material Support
Section 2339A condemns both providing material support and concealing “the nature, location,
source, or ownership” of such support. The concealing prong has been part of § 2339A from its
inception33 and seems designed to reach the middle men or conduits between terrorists and their
supporters. Expansion of the definition of material support to include services and the option of
charging middle men with conspiracy or aiding and abetting may have rendered the provision
redundant. In any event, concealment charges seem to have thus far been confined to those who
have also been charged with providing support.34

27 Dixon v. United States, 548 U.S. 1, 5 (2006) (quoting Bryan v. United States, 524 U.S. 184, 193 (1998)).
28 Id.; see also United States v. Morosco, 822 F.3d 1, 20 (1st Cir. 2016); United States v. Vereen, 920 F.3d 1300, 1307–
08 (11th Cir. 2019) (“[A] ‘knowing’ mens rea ‘merely requires proof of knowledge of the facts that constitute the
offense’ ‘[A] defendant need not intend to violate the law to commit a general intent crime, but he must actually intend
to do the act that the law proscribes.’”) (first quoting United States v. Vereen, 920 F.3d 1300, 1307; and then quoting
United States v. Phillips, 19 F.3d 1565, 1567–77 (11th Cir. 1994), amended, 59 F.3d 1095 (11th Cir. 1995)).
29 Food Mktg. Inst. v. Argus Leader Media, 139 S. Ct. 2356, 2362 (2019) (“But FOIA nowhere defines the term
‘confidential.’ So, as usual, we ask what that term’s ‘ordinary, contemporary, common meaning’ was when Congress
enacted FOIA in 1966.”); Wis. Cent. Ltd. v. United States, 138 S. Ct. 2067, 2072 (2018); Sandifer v. U.S. Steel Corp.,
571 U.S. 220, 227 (2014) (“[U]nless otherwise defined, words will be interpreted as taking their ordinary,
contemporary, common meaning (quoting Perrin v. United States, 444 U.S. 37, 42 (1979)); Taniguchi v. Kan Pac.
Saipan, Ltd., 566 U.S. 560, 566 (2012) (“When a term goes undefined in a statute, we give the term its ordinary
meaning.”).
30 Provide, MERRIAM-WEBSTER’S COLLEGIATE DICTIONARY (10th ed. 2002).
31 United States v. Sattar, 314 F. Supp. 2d 279, 297 (S.D.N.Y. 2004); United States v. Abu-Jihaad, 600 F. Supp. 2d 362,
399–400 (D. Conn. 2009); see also Estate of Parsons v. Palestinian Auth., 952 F. Supp. 2d 61, 68 (D.D.C. 2013)
(agreeing with the court in Abu-Jihaad).
32 18 U.S.C. § 2339C(e)(4). Section 2339C proscribes financing terrorism.
33 S. 266, § 2101 (102d Cong.); Violent Crime Control and Law Enforcement Act of 1994, Pub. L. No. 103-322,
§ 120005(a), 108 STAT. 2022 (codified at 18 U.S.C. § 2339A (1994)).
34 Kassir v. United States, 3 F.4th 556, 559 (2d Cir. 2021) (“various counts of (1) providing and concealing material
support and resources to terrorists, 18 U.S.C. §§ 2339A, 2339B . . .”); United States v. Stewart, 590 F.3d 93, 114 (2d
Cir. 2009) (“The government charged that the defendants provided ‘material support or resources’ in the form of
(continued...)
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Terrorist Material Support: An Overview of 18 U.S.C. § 2339A and § 2339B

Material Support
Section 2339A defines “material support” to encompass “any property, tangible or intangible, or
service.”35 The term excludes medicine and religious materials, but includes
• currency or monetary instruments or financial securities,
• financial services,
• lodging,
• training (i.e., instruction or teaching designed to impart a specific skill, as
opposed to general knowledge),
• expert advice or assistance (i.e., advice or assistance derived from scientific,
technical, or other specialized knowledge),
• safehouses,
• false documentation or identification,
• communications equipment, facilities,
• weapons,
• lethal substances,
• explosives,
• personnel (one or more individuals who may be or include oneself), and,
• transportation,
Section 2339B alone has a more explicit description of the “personnel” covered by its
proscription, which confines the term to those provided to a foreign terrorist organization to direct
its activities or to work under its direction or control.36 The omission of a comparable provision
from § 2339A led one court to conclude § 2339A does not include the “working under the
direction or control” limitation imposed on § 2339B.37 Because § 2339A requires that the support
be given while knowing or intending that it will be used in preparation for or in the commission
of a specific terrorist offense, the section has survived challenges arguing that it is
unconstitutionally vague.38

‘personnel. . . . . The government further asserted that Stewart and Yousry ‘conceal[ed] and disguise[d] the nature,
location, and source’ of their material support by means of the defendants’ covert conduct.”); United States v. Hassoun,
476 F.3d 1181, 1183–84 (11th Cir. 2007) (“Count Three charges the defendants with violating 18 U.S.C. § 2339A(a)
by providing material support and resources, and concealing and disguising the nature thereof, all with the knowledge
and intent that the material support and resources be used in preparation for and carrying out a violation of § 956.”);
United States v. Giampietro, 614 F. Supp. 3d 612, 614 (M.D. Tenn. 2022) (“[The defendant] did knowingly conceal
and disguise the nature, location, source, ownership, and control of material support and resources, as that term is
defined in Title 18, United States Code, Section 2339A(b)(1), knowing and intending that the support and resources,
including currency, personnel, and services, were provided and were intent to be provided in violation of Title 18,
United States Code, Section 2339B.”).
35 18 U.S.C. § 2339A(b)(1).
36 18 U.S.C. § 2339B(h) (“No person may be prosecuted under this section in connection with the term ‘personnel’
unless that person has knowingly provided, attempted to provide, or conspired to provide a foreign terrorist
organization with 1 or more individuals (who may be or include himself) to work under that terrorist organization’s
direction or control or to organize, manage, supervise, or otherwise direct the operation of that organization. Individuals
who act entirely independently of the foreign terrorist organization to advance its goals or objectives shall not be
considered to be working under the foreign terrorist organization’s direction and control.”).
37 United States v. Abu-Jihaad, 600 F. Supp. 2d 362, 400 (D. Conn. 2009).
38 Stewart, 590 F.3d at 117; United States v. Abu Khatallah, 151 F. Supp. 3d 116, 140 (D.D.C. 2015); United States v.
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Use in Relation to a Federal Crime of Terrorism
Section 2339A outlaws providing or concealing support when the defendant knows or intends the
support to be used in relation to a federal crime of terrorism. The intended support must be related
to the preparation for, commission of, or the escape following, the commission of one or more of
a list of predicate terrorist offenses. The predicate offense list consists of several specifically
identified offenses, such as bombing a federal building or murdering a federal official in the
performance of his duty.39 Section 2339A’s predicate offense list ends with a cross reference to
the list of federal crimes of terrorism.40 The predicate offenses, both those identified individually
and those included because of their status as federal crimes of terrorism may, but need not, be
calculated to serve terrorist purposes.41
Section 2339A bans attempts and conspiracies. Consequently, a violation of § 2339A may occur
even if the anticipated federal crime of terrorism has not.42 On the other hand, because the section

Amawi, 545 F. Supp. 2d 681, 684 (N.D. Ohio 2008); United States v. Abdi, 498 F. Supp. 2d 1048, 1058 (S.D. Ohio
2007).
39 18 U.S.C. § 2339A(a) (“Whoever provides material support . . . knowing or intending that [it is] to be used . . . in
carrying out a violation of section 32 [destruction of aircraft and aircraft facilities], 37 [violence at international
airports], 81 [arson within the special maritime and territorial jurisdiction of the United States, 175 [biological weapons
offenses], 229 [chemical weapons offenses], 351 [assassination, kidnapping, or assaulting Members of Congress, the
Supreme Court, or the Cabinet], 831 [transactions involving nuclear material], 844(m) [importing or exporting plastic
explosives without a detection agent], 842(n) [possession of a plastic explosive without a detection agent], 844(f)
[bombing federal property], 844(i) [bombing property used in, or affecting, interstate or foreign commerce], 930(c)
[killing a person in the course of an attack on a federal facility with a firearm or dangerous weapon], 956 [conspiracy to
kill, kidnap, maim, or injure individuals, or to damage property, in a foreign country], 1091 [genocide], 1114 [killing a
federal officer, employee, or member of the armed forces], 1116 [killing internationally protected individuals], 1203
[hostage taking], 1361 [destruction of federal property], 1362 [destruction of communication lines, stations or systems],
1363 [destruction of property in the special maritime and territorial jurisdiction of the United States], 1366 [destruction
of an energy facility], 1751 [assassination, kidnapping, or assaulting of the President, Vice President, or senior White
House staff members], 1992 [terrorist on mass transit), 2155 [destruction of national defense material], 2156
[production of defective national defense material), 2280 [violence against maritime navigation], 2281 [violence
against maritime fixed platforms], 2332 [killing or assaulting a United States national outside the United States], 2332a
[use of weapons of mass destruction], 2332b [multinational acts of terrorism], 2332f [bombing public places or
infrastructure facilities], 2340A [torture abroad], or 2442 [recruiting or using child soldiers] of this title; section 236 of
the Atomic Energy Act of 1954 (42 U.S.C. 2284) [sabotage of nuclear facilities or fuel]; section 46502 [aircraft piracy]
or 60123(b) [destruction of gas pipelines] of title 49. . . . ”).
40 18 U.S.C. § 2339A(a) (“Whoever provides material support . . . knowing or intending that [it is] to be used . . . in
carrying out a violation of . . . any offense listed in section 2332b(g)(5)(B) . . . .”). The cross reference to federal crimes
of terrorism adds the following offenses to § 2339A’s predicate offense list: offenses under (i) section 175b (biological
weapons), 175c (variola virus), 832 (participation in nuclear and weapons of mass destruction threats to the United
States), 1030(a)(1) (protection of computers), 1030(a)(5)(A) resulting in damage as defined in 1030(c)(4)(A)(i)(II)
through (VI) (protection of computers), 2156 (national defense material, premises, or utilities), 2281a (violence against
maritime fixed platforms), 2332g (missile systems designed to destroy aircraft), 2332h (radiological dispersal devices),
2332i (acts of nuclear terrorism), 2339C (financing of terrorism), 2339D (military-type training from a foreign terrorist
organization) of this title; (ii) section 92 (prohibitions governing atomic weapons) of the Atomic Energy Act of 1954
(42 U.S.C. § 2122); (iii) the second sentence of section 46504 (assault on a flight crew with a dangerous weapon),
section 46505(b)(3) or (c) (explosive or incendiary devices, or endangerment of human life by means of weapons, on
aircraft), section 46506 if homicide or attempted homicide is involved (application of certain criminal laws to acts on
aircraft) of title 49; or (iv) section 1010A of the Controlled Substances Import and Export Act (narco-terrorism).
41 The terrorist sentencing enhancement, however, only applies for support provided in relation to a predicate offense
calculated to serve terrorist purposes. U.S. SENT. GUIDELINES MANUAL § 3A1.4 cmt. app. n.1 (U.S. SENT’G COMM’N
2021); 18 U.S.C. § 2332b(g)(5)(A).
42 United States v. Hassoun, 476 F.3d 1181, 1188 (11th Cir. 2007) (“[T]he Government need not prove all the elements
of §956 [conspiracy to commit certain violent crimes overseas], the object offense, in order to satisfy the elements of
the substantive § 2339A charge. By its elements, § 2339A criminalizes material support given ‘in preparation for’ the
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also reaches support for concealment of an escape from a predicate offense, a violation of the
section may occur even after commission of the predicate offense.
Several of the predicate offense statutes cover, or consist solely of, conspiracy to violate their
proscription., For example, 18 U.S.C. § 956 prohibits conspiracy to commit certain violent crimes
overseas. Although the law ordinarily does not permit prosecution of a conspiracy to conspire, the
“[c]ourts have recognized that one conspiracy can serve as the predicate for another conspiracy
when the ‘[overarching] conspiracy and the predicate conspiracy are distinct offenses with
entirely different objectives.’”43
Attempt, Conspiracy, Aiding and Abetting
Section 2339A outlaws attempts as well as conspiracies to violate its proscriptions.44 In general,
attempt is the unfulfilled commission of an underlying offense. If the attempt succeeds, the
offender cannot be prosecuted or punished for both the completed offense and the attempt to
commit it.45 “Attempt” has two elements: (1) an intent to commit the underlying offense;46 and
(2) some substantial step towards its completion.47 Mere preparation is not enough.48 “To
constitute a substantial step, a defendant’s actions must cross the line between preparation and
attempt by unequivocally demonstrating that the crime will take place unless interrupted by
independent circumstances.”49 It is no defense that, unbeknownst to the defendant, commission of
the underlying offense was impossible, as for example because he was dealing with government
undercover agents rather than agents of a foreign terrorist organization.50 An attempt to provide
material support in violation of Section 2339A and providing that assistance are punished the
same: imprisonment for not more than 15 years (for any term of years or life, if death results from
the commission of the offense), a fine of not more than $250,000 (not more than $500,000 for an
organization) (or not more than twice the amount of gain or loss associated with the offense), or
both imprisonment and a fine.51
Conviction for conspiracy to violate § 2339A requires the government to “prove (1) that [the
defendant] entered into a conspiracy; (2) that the objective thereof was to provide support or

object offense – clearly, the object offense need not even have been completed yet, let alone proven as an element of
the material support offense. To meet its burden under § 2339A, the Government must at least prove that the
defendants provided material support or resources knowing that they be used in preparation for the § 956 conspiracy.”).
43 United States v. Khan, 461 F.3d 477, 493 (4th Cir. 2006) (alteration in original) (quoting United States v. Pugitore,
910 F.2d 1084, 1135 (3d Cir. 1990).
44 18 U.S.C. § 2339A(a).
45 United States v. Rivera-Relle, 333 F.3d 914, 921 n.11 (9th Cir. 2003).
46 United States v. Farhane, 634 F.3d 127, 145–46 (2d Cir. 2011); United States v. Hossain, 579 F. Supp. 3d 477, 480
(S.D.N.Y. 2022).
47 Braxton v. United States, 500 U.S. 344, 349 (1991); United States v. Mehanna, 735 F.3d 32, 53 (1st Cir. 2013);
Hossain, 579 F. Supp. 3d at 480.
48 United States v. Barlow, 568 F.3d 215, 219 (5th Cir. 2009); United States v. DeMarce, 564 F.3d 989, 998 (8th Cir.
2009); Hossain, 579 F. Supp. 3d at 480.
49 United States v. Mincoff, 574 F.3d 1186, 1195 (9th Cir. 2009) (quoting United States v. Goetzke, 494 F.3d 1231,
1237 (9th Cir. 2007)); United States v. Morris, 549 F.3d 548, 550 (7th Cir. 2008); see also Hossain, 579 F. Supp. 3d at
481 (“a substantial step towards the provision of material support need not be planned to culminate in actual terrorist
harm, but only in support – even benign support – for an organization committed to such harm.”) (quoting United
States v. Farhane, 634 F.3d 127, 148 (2d Cir. 2011)).
50 Mehanna, 735 F.3d at 53; see also United States v. Rehak, 589 F.3d 965, 970–71 (8th Cir. 2009); United States v.
Coté, 504 F.3d 682, 687–88 (7th Cir. 2007); cf. United States v. Lakhani, 480 F.3d 171, 174–77 (3d Cir. 2007).
51 18 U.S.C. §§ 2339A(a), 3571.
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resources; and (3) that he then knew and intended that such support or resources would be used in
preparation for, or in carrying of [a predicate offense].”52 No First Amendment violation occurs
when the government introduces at trial evidence of the defendant’s conspiratorial statements.
“Forming an agreement to engage in criminal activities – in contrast with simply talking about
religious or political beliefs – is not [First Amendment] protected speech.”53
In general, the offense of conspiracy to provide material support is complete upon assent; the
support need only be planned, not delivered.54 Moreover, each of the conspirators is liable not
only for the conspiracy, but for any other foreseeable offense committed by any of the
conspirators in furtherance of the overall scheme.55 Like attempt, conspiracy to provide material
support carries the same penalties as the completed substantive offense: imprisonment for not
more than 15 years (for any term of years or life, if death results from the commission of the
offense), or a fine of not more than $250,000 (not more than $500,000 for an organization)(or not
more than twice the amount of gain or loss associated with the offense), or both imprisonment
and a fine.56 Unlike attempt, conspirators may be punished for both conspiracy and for providing
material support should their scheme succeed.57
Under 18 U.S.C. § 2, anyone who counsels, procures, aids, or abets a violation of Section 2339A
or any other federal crime is punishable as though he had committed the offense himself. “In
order to aid and abet another to commit a crime it is necessary that a defendant in some sort
associate himself with the venture, that he participate in it as in something that he wishes to bring
about, [and] that he seek by his action to make it succeed.”58 “Typically, the same evidence will
support both a conspiracy and an aiding and abetting conviction.”59 Unlike conspiracy, however,
liability under Section 2 only attaches if someone else commits the substantive offense.60

52 United States v. Hassan, 742 F.3d 104, 140 (4th Cir. 2014); United States v. Stewart, 590 F.3d 93, 114–16 (2d Cir.
2010); Chapman v. United States, 326 F. Supp. 3d 228, 242 (E.D. Va. 2018); see generally JOSEPH F. MCSORLEY, A
PORTABLE GUIDE TO FEDERAL CONSPIRACY LAW (1996); CRS Report R41223, Federal Conspiracy Law: A Brief
Overview
, by Charles Doyle.
53 Hassan, 742 F.3d at 127 (quoting United States v. Amawi, 695 F.3d 457, 482 (6th Cir. 2012)).
54 Rehak, 589 F.3d at 971; United States v. Schaffer, 586 F.3d 414, 422 (6th Cir. 2009); United States v. Moalin, 973
F.3d 977, 1006–07 (9th Cir. 2020) (“None of the three conspiracy counts [under §§ 2339A and 2339B] required the
prosecution to prove that Doreh committed an overt act in furtherance of the conspiracy.”).
55 Pinkerton v. United States, 328 U.S. 640, 647 (1946); United States v. Merlino, 592 F.3d 22, 29 (1st Cir. 2010);
United States v. Wardell, 591 F.3d 1279, 1291 (10th Cir. 2009); United States v. Khatallah, 41 F.4th 608, 625–26 (D.C.
Cir. 2022).
56 18 U.S.C. §§ 2339A(a), 3571.
57 Iannelli v. United States, 420 U.S. 770, 777–78 (1975); United States v. Chandia, 514 F.3d 365, 372 (4th Cir. 2008)
(“We also disagree with Chandia’s argument that Congress did not intend to authorize multiple punishments for a
conspiracy and a substantive violation under § 2339B. Chandia’s argument is based on the language of the statute,
which prohibits the conspiracy and the actual provision of material support in the same section. See 18 U.S.C. §
2339B(a)(1). (‘Whoever knowingly provides material support . . . or attempts or conspires to do so . . .’). But, as the
Supreme Court has held, the ‘settled principle’ that ‘the commission of the substantive offense and a conspiracy to
commit it are separate and distinct offenses’ does not give way simply because the statute describing the substantive
offense also specifically prohibits conspiracies.” (alterations in original) (quoting Callanan v. United States, 364 U.S.
587, 593 (1961)).
58 Nye & Nissen v. United States, 336 U.S. 613, 619 (1949); see also Rosemond v. United States, 572 U.S. 65, 17
(2014) (“As at common law, a person is liable under § 2 for aiding and abetting a crime if (and only if) he (1) takes an
affirmative act in furtherance of that offense, (2) with the intent of facilitating the offense’s commission”); United
States v. Little, 829 F.3d 1177, 1184 (10th Cir. 2016).
59 United States v. Vasquez, 677 F.3d 685, 695 (5th Cir. 2012); see also United States v. Boria, 592 F.3d 476, 481 n.8
(3d Cir. 2010).
60 United States v. Cruickshank, 837 F.3d 1182, 1189 (11th Cir. 2016); United States v. Lange, 834 F.3d 58, 69 (2d Cir.
2016); United States v. Gaw, 817 F.3d 1, 7 (1st Cir. 2016).
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Consequences of Charge or Conviction
Section 2339A convictions carry a sentence of imprisonment for not more than 15 years (for any
period of years or for life if death results from commission of the offense) or a fine of not more
than $250,000 (not more than $500,000 for an organizational defendant), or both imprisonment or
a fine.61 The Sentencing Guidelines influence the sentence imposed below the statutory
maximum.62 Sentencing courts must begin the process by determining the sentence range
recommended by the Guidelines.63 Either the defendant or the government or both, may seek
appellate court review of the sentence imposed to ensure that it is procedurally and substantively
reasonable.64 A sentence is procedurally unreasonable, among other things, if it results from a
Guideline miscalculation.65 A sentence is substantively unreasonable, if it is unduly lenient or
severe based on the nature and severity of the offense and the defendant’s circumstances.66
The Sentencing Guidelines treat § 2339A convictions as if they were convictions for aiding and
abetting or for being an accessory after the fact and set the Guideline range using that of the
predicate offense.67 The Guidelines feature a terrorism adjustment which can raise the Guideline
sentencing level, for an offense that “involved or was intended to promote a federal crime of
terrorism.”68 A federal crime of terrorism is one “calculated to influence or affect the conduct of
[a] government by intimidation or coercion, or to retaliate against government conduct.” The
standard “does not focus on the defendant but on his ‘offense,’ asking whether it was calculated,
i.e., planned – for whatever reason or motive – to achieve the stated object.”69 The sentencing
court is free, but not obligated, to depart from the enhancement.70
Federal Crime of Terrorism
Section 2339A is among those statutes whose proscription is listed in the statute defining federal
crimes of terrorism.71 Classification as a federal crime of terrorism has several other
consequences. Property derived from or used in the commission of such an offense is subject to

61 18 U.S.C. §§ 2339A(a), 3571.
62 See generally CRS Report R41696, How the Federal Sentencing Guidelines Work: An Overview, by Charles Doyle.
63 Gall v. United States, 552 U.S. 38, 49 (2007); United States v. Stewart, 590 F.3d 93, 134 (2d Cir. 2009).
64 18 U.S.C. § 3742.
65 Gall, 552 U.S. at 51; United States v. Hammadi, 737 F.3d 1043, 1047 (6th Cir. 2013).
66 Gall, 552 U.S. at 51; see also Hammadi, 737 F.3d at 1047; United States v. Mohamed, 757 F.3d 757, 761 (8th Cir.
2014) (“[W]here a district court has sentenced a defendant below the advisory guidelines range, it is nearly
inconceivable that the court abused its discretion” and imposed a substantively unreasonable sentence) (alteration in
original) (quoting United States v. Worthey, 716 F.3d 1107, 1116 (8th Cir. 2013)).
67 U.S. SENT’G GUIDELINES MANUAL §§ 2X2.1, 2X3.1 (U.S. SENT’G COMM’N 2021).
68 Id. § 3A1.4 (“(a) If the offense is a felony that involved, or was intended to promote a federal crime of terrorism,
increase by 12 levels; but if the resulting offense level is less than level 32, increase to level 32. (b) In each such case,
the defendant’s criminal history category . . . shall be Category VI”). The recommended sentencing range for level 32,
category VI is from 210 to 262 months imprisonment. The maximum sentence for a violation of § 2339A is 15 years.
18 U.S.C. § 2339A(a). Therefore, the maximum sentence is imprisonment for 180 months, unless the defendant is
convicted of additional offenses. See, e.g., United States v. Hassan, 742 F.3d 104, 147 (4th Cir. 2014) (“The court
calculated Sherifi’s advisory Guidelines ranges as follows: 180 months (the statutory maximum) on Count One [(18
U.S.C. § 2339A)]; life in prison on Count Two [18 U.S.C. § 956] and life in prison on Count Eleven [18 U.S.C.
§ 1117]. Rather than a life sentence, the court imposed an aggregate sentence of 540 months.”).
69 Mohamed, 757 F.3d at 760 (quoting United States v. Awan, 607 F.3d 306, 317 (2d Cir. 2010)).
70 United States v. Kabir, 51 F.4th 820, 828–29 (9th Cir. 2022) (citing, inter alia, Kimbrough v. United States, 552 U.S.
85, 91 (2007)).
71 18 U.S.C. § 2332b(g)(5)(B).
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confiscation.72 Federal crimes of terrorism are by definition predicate offenses under federal
money laundering and RICO prosecutions.73 Section 2339A prosecutions are subject to an eight-
year statute of limitations, rather than the general five-year period.74 An accused charged with a
violation of a federal crime of terrorism faces an enhanced prospect of pre-trial detention.75 A
defendant convicted for violating a federal crime of terrorism may be subject to a life-time term
of supervised release, rather than the general five-year maximum term.76
Extraterritorial Jurisdiction
Unlike § 2339B, § 2339A has neither a general nor a descriptive statement of extraterritorial
jurisdiction. Historically, a court would find a statute’s provisions applicable overseas under any
of several circumstances. First, courts have found extraterritorial jurisdiction applied to overseas
accomplices to crimes with extraterritorial application.77 Second, courts have found statutes
applied abroad when confining application to purely domestic violations would likely frustrate
congressional intent and the purpose for the statute’s enactment.78 Third, overseas violations of
this provision would be prosecutable under circumstances evidencing one or more of the
principles that justify the exercise of federal jurisdiction under international law, for example, the
offense has an impact in the United States (territorial principle); the offender is a U.S. national
(nationality principle); the victim is a U.S. national (passive personality principle); the offense

72 18 U.S.C. § 981(a)(1)(G).
73 18 U.S.C. §§ 1956(c)(7)(D), 1961(1)(G). Among other things, the federal racketeering statute prohibits conducting,
through the patterned commission of more than one predicate offense, the affairs of an enterprise whose activities affect
interstate or foreign commerce, 18 U.S.C. §§ 1962, 1961. Among other things, the principal federal money laundering
statute prohibits engaging in a financial transaction involving the proceeds of a predicate offense when the transaction
is designed to launder the proceeds or to use them to promote further predicate offenses, 18 U.S.C. §§ 1956(a)(1),
(c)(7).
74 18 U.S.C. §§ 3286(a), 3282. Prosecution of a federal crime of terrorism may be brought at any time if the offense
involves the risk of serious bodily injury, 18 U.S.C. § 3286(b).
75 18 U.S.C. § 3142(f)((1)(A), (g)(1); United States v. Hir, 517 F.3d 1081, 1086 (9th Cir. 2008) (“Where, as here, there
is probable cause to believe that the defendant has committed an offense identified as a ‘federal crime of terrorism
under 18 U.S.C. § 2332b(g)(5)(B) for which a maximum term of imprisonment of ten years or more is prescribed, there
is a rebuttable presumption that ‘no condition or combination of conditions will reasonably assure the appearance of the
person as required and the safety of the community.’ 18 U.S.C. § 3142(e). Although the presumption shifts a burden of
production to the defendant, the burden of persuasion remains with the government.’”); see also United States v.
Mehanna, 669 F. Supp. 2d 160, 164–65 (D. Mass. 2009).
76 18 U.S.C. § 3583(j), (b).
77 United States v. Felix-Gutierrez, 940 F.2d 1200, 1205 (9th Cir. 1991) (“We conclude that the crime of ‘accessory
after the fact’ gives rise to extraterritorial jurisdiction to the same extent as the underlying offense. That is, if the
underlying substantive statute applies extraterritorially, the statute making it unlawful to assist another in avoiding
apprehension, trial or punishment also applies extraterritorially when invoked in connection with an extraterritorial
violation of the underlying statute. . . . We have inferred extraterritorial application of conspiracy statutes on the basis
of a finding that the underlying substantive statutes reach extraterritorial offenses. We see no reason why a different
rule should apply in accessory after the fact cases” (citations omitted)); see also United States v. Abu Khatallah, 151 F.
Supp. 3d 116, 138 (D.D.C. 2015).
78 United States v. Bowman, 260 U.S. 94, 98 (1922) (Some offenses “are such that to limit their locus to the strictly
territorial jurisdiction would be greatly to curtail the scope and usefulness of the statute and leave open a large
immunity for frauds as easily committed by citizens on the high seas and in foreign countries as at home. In such cases,
Congress has not thought it necessary to make specific provision in the law that the locus shall include the high seas
and foreign countries, but allows it to be inferred from the nature of the offense”); see also United States v. Al Kassar,
660 F.3d 108, 118 (2d Cir. 2011); United States v. Georgescu, 148 F. Supp. 3d 319, 323–24 (S.D.N.Y. 2015).
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affects U.S. nationwide interests (protective principle); or the offense is universally condemned
(universal principle).79
Today, Section 2339A’s application abroad still extends as far as the extraterritorial application of
its predicate offenses.80 Otherwise, as the Supreme Court declared in RJR Nabisco, Inc. v.
European Community
: “Absent clearly expressed congressional intent to the contrary, federal
laws will be construed to have only domestic application.”81 The Court explained that, “[t]he
question is not whether we think ‘Congress would have wanted’ a statute to apply to foreign
conduct ‘if it had thought of the situation before the court,’ but whether Congress has affirmative
and unmistakably instructed that the statute will do so. ‘When a statute gives no clear indication
of an extraterritorial application, it has none.’”82
Venue
Section 2339A asserts that venue is proper in “any Federal judicial district in which the
underlying offense was committed, or in any other Federal judicial district as provided by law.”83
Moreover as a general rule, the law provides that conspiracy to commit an offense may be tried
wherever an act in furtherance of the conspiracy occurs.84 Crimes committed abroad may be tried
where the accused is first brought into the United States.85 Venue is also proper where the accused
aided and abetted the commission of a completed offense.86 Section 2339A’s reach, when based
solely on the location of the completed predicate offense, may be limited by Supreme Court
decisions suggesting that venue over offenses committed within the United States is only proper
in those districts in which a conduct element of the offense occurs.87

79 United States v. Clark, 435 F.3d 1100, 1106 (9th Cir. 2006); United States v. Yousef, 327 F.3d 56, 90-91 (2d Cir.
2003); United States v. MacAllister, 160 F.3d 1304, 1308 (11th Cir. 1998); United States v. Al-Imam, 373 F. Supp. 3d
247, 266 (D.D.C. 2019) (“Al-Imam and the Government agree that § 2339A . . . applies extraterritorially to the extent
that an associated substantive offense does.”).
80 RJR Nabisco, Inc. v. Eur. Cmty., 579 U.S. 325, 338 (2016) (“We find that the presumption against extraterritoriality
has been rebutted – but only with respect to certain applications of the statute. The most obvious textual clue is that
RICO defines racketeering activity to include a number of predicates that plainly apply to at least some foreign
conduct.”).
81 Id. at 335.
82 Id. (quoting Morrison v. Nat’l Austl. Bank Ltd., 561 U.S. 247 (2010)).
83 18 U.S.C. § 2339A(a).
84 Whitfield v. United States, 543 U.S. 209, 218 (2005); United States v. Matthews, 31 F.4th 436, 455 (6th Cir. 2022);
United States v. Heatherly, 985 F.3d 254, 263 (3d Cir. 2021); United States v. Lee, 966 F.3d 310, 319 (5th Cir. 2020);
United States v. Sitzmann, 893 F.3d 811, 826 (D.C. Cir. 2018). See generally CRS Report RL33223, Venue: A Legal
Analysis of Where a Federal Crime May Be Tried
, by Charles Doyle.
85 18 U.S.C. § 3238 (“The trial of all offenses begun or committed upon the high seas, or elsewhere out of the
jurisdiction of any particular State or district, shall be in the district in which the offender, or any one of two or more
joint offenders, is arrested or is first brought; but if such offender or offenders are not so arrested or brought into any
district, an indictment or information may be filed in the district of the last known residence of the offender or of any
one of two or more joint offenders, or if no such residence is known the indictment or information may be filed in the
District of Columbia.”).
86 United States v. Khalupsky, 5 F.4th 279, 291 (2d Cir. 2021); United States v. Thomas, 690 F.3d 358, 370 (5th Cir.
2012); cf. United States v. Cabrales, 524 U.S. 1, 7 (1998) (holding that money laundering in Florida of the proceeds
generated by a Missouri drug trafficking enterprise could not be tried in Missouri, but suggesting that venue might have
been proper had the laundering be charged as aiding and abetting the Missouri trafficking: “Nor do they charge her as
an aider or abettor in the Missouri drug trafficking”).
87 United States v. Rodriguez-Moreno, 526 U.S. 275, 279 (1999); Cabrales, 524 U.S. at 6–7.
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Defenses
Defendants have occasionally attempted to claim combat immunity as a defense, but no
court has yet accepted the defense under § 2339A.88
Civil Actions
Section 2339A, like § 2339B, creates no private cause of action. Still, 18 U.S.C. § 2333
authorizes such suits for those injured in their person, property, or business “by reason of” an act
of international terrorism.89 Section 2331(1) defines the term “international terrorism” under the
chapter in which §§ 2333, 2339A, and 2339B are found.90 The term features three elements: a
dangerous crime,91 a terrorist motive,92 and an international component.93 The courts have
concluded that the violations of § 2339A or § 2339B may satisfy the first of these elements.94

88 E.g., United States v. Hamidullin, 888 F.3d 62, 71 (4th Cir. 2018) (a Taliban-affiliated former Russian Army officer
fighting in Afghanistan was not entitled to immunity because the conflict at the time was not an international conflict
for purposes of the Geneva Convention); United States v. Harcevic, 999 F.3d 1172, 1176 (8th Cir. 2021) (participants
in the Syrian Civil War are not entitled to immunity because the conflict is not international conflict); United States v.
Hodzic, 355 F. Supp. 3d 825, 827–28 (E.D. Mo. 2019) (same).
89 18 U.S.C. § 2333(a) (“Any national of the United States injured in his or her person, property, or business by reason
of an act of international terrorism, or his or her estate, survivors, or heirs, may sue therefor in any appropriate district
court of the United States and shall recover threefold the damages he or she sustains and the cost of the suit, including
attorney’s fees.”).
90 18 U.S.C. § 2331(1) (“As used in this chapter- (1) the term "international terrorism" means activities that-
(A) involve violent acts or acts dangerous to human life that are a violation of the criminal laws of the United States or
of any State, or that would be a criminal violation if committed within the jurisdiction 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; and (C) occur primarily outside the territorial jurisdiction of the United States, or
transcend national boundaries in terms of the means by which they are accomplished, the persons they appear intended
to intimidate or coerce, or the locale in which their perpetrators operate or seek asylum.”).
91 Id. § 2331(1)(A) (“the term ‘international terrorism’ means activities that – (A) involve violent acts or acts dangerous
to human life that are a violation of the criminal laws of the United States or of any State, or that would be a criminal
violation if committed within the jurisdiction of the United States or of any State. . . .”).
92 Id. § 2331(1)(B) (“the term ‘international terrorism’ means activities that – . . . (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 . . . .”).
93 Id. § 2331(1)(C) (“the term ‘international terrorism’ means activities that – . . . (C) occur primarily outside the
territorial jurisdiction of the United States, or transcend national boundaries in terms of the means by which they are
accomplished, the persons they appear intended to intimidate to coerce, or the locale in which their perpetrators operate
or seek asylum.”).
94 Weiss v. Nat’l Westminster Bank, PLC, 993 F.3d 144, 156 (2d Cir. 2021) (“‘conduct that violates a material support
statute can also satisfy the § 2331(1) definition requirements of international terrorism in some circumstances.’”)
(emphasis of the court) (quoting Linde v. Arab Bank, PLC, 882 F.3d 314, 326 (2d Cir. 2018); Crosby v. Twitter, Inc.,
921 F.3d 617, 622 (6th Cir. 2019) (“Under 18 U.S.C. § 2339B(a)(1), it is a crime to provide material support to a
foreign terrorist organization. And if that material support also qualifies as an act of ‘international terrorism’ under 18
U.S.C. § 2331(1), a plaintiff can recover for injuries that occurred ‘by reason of’ the defendant’s conduct. 18 U.S.C.
§ 2333(a).”); Boim v. Quranic Literacy Inst., 291 F.3d 1000, 1015 (7th Cir. 2002) (“If the plaintiffs could show that
[defendants] violated either section 2339A or section 2339B, that conduct would certainly be sufficient to meet the
definition of ‘international terrorism’ under sections 2333 and 2331. . . Congress has made clear, though, through the
criminal liability imposed in sections 2339A and 2339B, that even small donations made knowingly and intentionally
in support of terrorism may meet the standard for civil liability in section 2333.”).
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They do so by construing violations of § 2339A or § 2339B as acts of “international terrorism” as
defined in 18 U.S.C. § 2331(1).95
In 2016, Congress expanded the reach of § 2333 in the Justice Against Sponsors of Terrorism Act
(JASTA) to include liability for aiding and abetting an act of terrorism.96 The expansion
contemplated liability that satisfied Halberstam’s three elements: “(1) the party whom the
defendant aids must perform a wrongful act that causes an injury; (2) the defendant must be
generally aware of his role as part of an overall illegal or tortious activity at the time that he
provides the assistance; and (3) the defendant must knowingly and substantially assist the
principal violation.”97
In Twitter, Inc. v. Taamneh,98 the Supreme Court rejected claims that three social media
companies, Facebook, Twitter, and Google (YouTube), whose platforms terrorists had used to
recruit and raise funds, were liable for aiding and abetting a terrorist attack on an Istanbul
nightclub that killed 39 and injured another 69. The Court explained that for purposes of § 2333
aiding and abetting liability is confined to “a conscious, voluntary, and culpable participation in”
in someone else’s wrongdoing.”99

95 Boim v. Holy Land Found., 549 F.3d 685, 690 (7th Cir. 2008) (en banc) (“The first panel opinion discussed
approvingly an alternative and more promising ground for bringing donors to terrorist organizations within the grasp of
section 2333. The ground involves a chain of explicit statutory incorporations by reference. The first link in the chain is
the statutory definition of ‘international terrorism’ as ‘activities that . . . involve violent acts or acts dangerous to human
life that are a violation of the criminal laws of the United States,’ that ‘appear to be intended . . . to intimidate or coerce
a civilian population’ or ‘affect the conduct of a government by . . . assassination,’ and that ‘transcend national
boundaries in terms of the means by which they are accomplished’ or ‘the persons they appear intended to intimidate or
coerce.’ Section 2331(1) . . . includes not only violent acts but also ‘acts dangerous to human life that are a violation of
the criminal laws of the United States.’ Giving money to Hamas, like giving a loaded gun to a child (which also is not a
violent act), is an ‘act dangerous to human life.’ And it violates . . . 18 U.S.C. § 2339A(a), which provides that
‘whoever provides material support or resources . . . , knowing or intending that they are to be used in preparation for,
or in carrying out, a violation of [e.g.,] [18 U.S.C. § 2332],’ shall be guilty of a federal crime. So we go to 18 U.S.C.
§ 2332 and discover that it criminalizes the killing [of] . . . any American citizen outside the United States. By this
chain of incorporations by reference (section 2333(a) to section 2331(1) to section 2339A to section 2332), we see that
a donation to a terrorist group that targets Americans outside the United States may violate section 2333.” (alterations
4, 5, 7, 8, 9 in original)); Goldberg v. UNS AG, 690 F. Supp. 2d 92, 113 (E.D.N.Y. 2010) (“[S]ections 2339A and
2339B make clear Congress’ intent that the intentional (or reckless) provision of material support to a terrorist
organization fulfills each prong of section 2331(1)’s definition of ‘international terrorism,’ and therefore suffice to
establish liability under section 2333(a).”).
96 18 U.S.C. § 2333(d)(2) (“Liability.-In an action under subsection (a) for an injury arising from an act of international
terrorism committed, planned, or authorized by an organization that had been designated as a foreign terrorist
organization under section 219 of the Immigration and Nationality Act (8 U.S.C. 1189), as of the date on which such
act of international terrorism was committed, planned, or authorized, liability may be asserted as to any person who
aids and abets, by knowingly providing substantial assistance, or who conspires with the person who committed such
an act of international terrorism.”).
97 Siegel v. HSBC N. Am. Holdings, Inc., 933 F.3d 217, 223 (2d Cir. 2019) (“JASTA further states that Halberstam v.
Welch
, 705 F.2d 472 (D.C. Cir. 1983), provides ‘the proper legal framework’ for ‘[f]ederal civil aiding and abetting and
conspiracy liability.’” (alteration in original) (quoting JASTA, § 2(a)(5), 130 STAT. 852)); Atchley v. AstraZeneca UK
Ltd., 22 F.4th 204, 216 (D.C. Cir. 2022) (“Plaintiffs thus need to plead three statutory elements: (1) an injury arising
from an act of international terrorism; (2) that the act was committed, planned, or authorized by a designated Foreign
Terrorist Organization; and (3) that defendants aided or abetted an act of international terrorism by knowingly
providing substantial assistance. As discussed below, Halberstam, in turn, spells out three elements that establish the
referenced aiding or abetting – wrongful acts, general awareness, and substantial assistance – and further guides our
consideration by reference to six ‘substantial assistance factors [i.e., nature of the act assisted, amount of assistance,
present at the time, relation to the tortious actor, defendant’s state of mind, and duration of the assistance].’” (citing
Halberstam v. Welch, 705 F.2d 472, 487–88 (D.C. Cir. 1983)).
98 143 S. Ct. 1206 (2023)
99 Id. at 1223.
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Like § 2333, the Sherman Act, the Clayton Act and RICO each afford relief from injuries incurred
“by reason of” a violation of their provisions.100 Moreover, “the Supreme Court has repeatedly
and explicitly held that when Congress uses the phrase ‘by reason of’ in a statute, it intends to
require a showing of proximate cause.”101 The precise definition of the term has proven elusive.102
The term can have a pragmatic quality, for “[a]t bottom, [it] reflects ‘ideas of what justice
demands, or of what is administratively possible and convenient.’”103
In the context of § 2333, some courts have held that proximate cause exists where (1) “the
defendants’ acts were a substantial factor in the sequence of events that led to the plaintiffs’
injuries;” and (2) “those injuries were ‘reasonably foreseeable or anticipated as a natural
consequences of’ defendants’ conduct.”104
An injury has been incurred “by reason of” an act of international terrorism when an act of
international terrorism was the proximate cause of the injury.105 “That said, we know that simply
stating that [§ 2333] requires proof of ‘probable cause’ does not help much.”106 “[F]oreseeability,
directness, and the substantiality of the defendant’s conduct – are relevant to the inquiry . . . we
use ‘proximate cause’ to label generically the judicial tools used ‘to perform an inquiry that
ultimately reflects ideas of what justice demands, and of what is administratively possible and
convenient.’”107

100 Fields v. Twitter, Inc., 881 F.3d 739, 744 (9th Cir. 2018). RICO refers to the Racketeer Influenced and Corrupt
Organization provisions of 18 U.S.C. §§1961–1968.
101 Kemper v. Deutsche Bank AG, 911 F.3d 383, 391 (7th Cir. 2018) (citing Holmes v. Sec. Inv. Prot. Corp., 503 U.S.
258, 267–68 (1992); Associated Gen Contractors of Cal., Inc., v. Cal. State Council of Carpenters, 459 U.S. 519, 532–
35 (1983); Hemi Grp., LLC v. City of New York, 559 U.S. 1, 9 (2010)).
102 Kemper, 911 F.3d at 392 (“A firm definition of the term ‘proximate cause’ has escaped judges, lawyers, and legal
scholars for centuries. . . . The term has so bedeviled the authors of the Restatement of Torts that they omitted it
entirely from the First and Second Restatements and expressed a wish for its extermination in the Third.”).
103 Holmes, 503 U.S. at 268 (quoting W. PAGE KEETON, ET AL., PROSSER AND KEETON ON THE LAW OF TORTS § 41, p.
264 (5th ed. 1984)).
104 Crosby v. Twitter, Inc., 921 F.3d 617, 624 (6th Cir. 2019) (citing cases from the D.C. and Second Circuits.).
105 Id. at 623 (“We know that proximate cause is required under [§ 2333] by looking at the language of the statute,
which limits recovery to injuries sustained ‘by reason of an act international terrorism.’ ‘[T]he Supreme Court has
repeatedly and explicitly held that when Congress uses the phrase “by reason of” in a statute, it intends to require a
showing of proximate cause’” (citing Holmes v, Sec. Inv. Prot. Corp., 503 U.S. 258, 267–68 (1992); Associated Gen.
Contractors of Cal. v. Cal. State Council of Carpenters, Inc., 459 U.S. 519, 532–35 (1983); and Hemi Group, LLC v.
City of New York, 559 U.S. 1 (2010)). And the Second, Ninth, and D.C. Circuits have all reached the same conclusion:
proximate cause is required under [§ 2333]’ (citing, Owens v. BNP Paribas, S.A., 897 F.3d 266, 273 (D.C. Cir. 2018);
Fields v. Twitter, Inc., 881 F.3d 739, 744–45 (9th Cir. 2018); Rothstein v. UBS AG, 708 F.3d 82, 95–96 (2d Cir.
2013)013).”).
106 Id. (quoting Kemper, 911 F.3d at 392.
107 Kemper, 911 F.3d at 392 (quoting Holmes, 503 U.S. at 268)); see also Owens, 897 F.3d at 273 (“Plaintiffs must
therefore plausibly allege (1) that BNPP’s acts were ‘a substantial factor’ in the sequence of events that led to their
injuries and (2) that those injuries must have been reasonably foreseeable or anticipated as a natural consequence of
BNPP’s conduct.”).
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Terrorist Material Support: An Overview of 18 U.S.C. § 2339A and § 2339B

Litigation under § 2333 is governed by several other statutory provisions that are beyond the
scope of this report.108 The results show, however, that claimants have had trouble recovering on
their claims.109
Support of Designated Terrorist Organizations
(18 U.S.C. § 2339B)
Section 2339A condemns providing material support for crimes that may be committed in a
terrorism context. Section 2339B condemns providing material support to foreign terrorist
organizations that engage in such offenses.110 In its present form, § 2339B provides for criminal
liability against:
(1) whoever
(2) knowingly
(3)(a) attempts to provide,
(b) conspires to provide, or
(c) provides
(4) material support or resources
(5) to a foreign terrorist organization
(6) knowing that the organization
(a) has been designated a foreign terrorist organization, or

108 E.g., 18 U.S.C. §§ 2334 (relating to jurisdiction and venue), 2335 (relating to statute of limitations), 2336 (relating
to other limitations), 2337 (relating to suits against government officials), 2338 (relating to exclusive federal
jurisdiction). See CRS Report R46274, The Palestinians and Amendments to the Anti-Terrorism Act: U.S. Aid and
Personal Jurisdiction
, by Jim Zanotti & Jennifer K. Elsea.
109 E.g., Seigel v. HSBC N. Am. Holdings, 933 F.3d 217, 219 (2d Cir. 2019) (“[B]ecause the plaintiffs did not
adequately allege . . . that the defendants [(financial institutions that provided banking services to a Saudi bank that in
turn provided services to the terrorist organization)] knowingly played a role in the November 9 [terrorist] attacks or
provided substantial assistance to the terrorist organization that perpetrated it, they failed to a plausible claim for relief
under JASTA.”); Crosby, 921 F.3d at 619 (“[Victims’] Plaintiffs’ complaint includes no allegations that Twitter,
Facebook, or Google (who allegedly hosted terrorist propaganda that ‘virtual recruit[ed] Americans to commit terrorist
attacks’) had any direct connection to Mateen or his heinous act.”); Kemper, 911 F.3d at 386 (“[D]espite Congress’s
effort to make state sponsors of terrorism accountable in U.S. courts, see 28 U.S.C. § 1605A, any resulting judgment
may be uncollectible. Rhonda Kemper attempted to get around these formidable obstacles by alleging that the bomb
that killed her son was a signature Iranian weapon that traveled from the Iranian Revolutionary Guard Corps (‘the
Guard’) to Hezbollah to Iraqi militias, who then placed it in the ground . . . where it killed Spc. Schaefer. Kemper
asserts that Deutsche Bank AG, a German entity with U.S. affiliates, is responsible for her son’s death under . . . 18
U.S.C. § 2333. She ties Deutsche to the fatal bomb through the Bank’s alleged membership in an Iranian conspiracy to
commit acts of terror. It joined that conspiracy, she contents, when it instituted procedures to evade U.S. sanctions and
facilitate Iranian banking transactions. The district court found that Kemper failed to plead facts that plausible indicated
that Deutsche Bank’s actions caused her son’s death . . . We affirm.” (citations omitted)).
110 Providing material support to foreign terrorist organizations is reminiscent of one of the elements of treason,
“adhering to [the] Enemies” of the United States. U.S. CONST. art. III, § 3, cl. 1 (“Treason against the United States,
shall consist only in levying War against them, or in adhering to their Enemies, giving them Aid and Comfort. No
Person shall be convicted of Treason unless on the Testimony of two Witnesses to the same overt Act, or on
Confession in open Court.”). Congress added an additional element to the treason statute, 18 U.S.C. § 2382. The
offense can only be committed by one “owing allegiance to the United States,” id., which puts an end to the argument
that § 2339A and § 2339B offenses must be tried as treason, United States v. Augustin, 661 F.3d 1105, 1117 (11th Cir.
2011) (citing in accord United States v. Rahman, 189 F.3d 88, 113 (2d Cir. 1999) and United States v. Rodriguez, 803
F.2d 318, 329 (7th Cir. 1986)) (“[W]e note that neither § 2339A nor § 2339B – the two statutes under which Augustine
was convicted – include allegiance to the United States as an element of the offense. Thus, we have no trouble
concluding that these offenses, as defined by Congress do not fall within the ambit of the Treason Clause”).
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(b) engages, or has engaged, in “terrorism” or “terrorist activity.”111
Whoever
The law here for § 2339B is the same as for § 2339A. “Whoever” usually means any legal entity
or individual.112 The Dictionary Act declares that “In determining the meaning of any Act of
Congress, unless the context indicates otherwise . . . the words ‘person’ and ‘whoever’ include
corporations, companies, associations, firms, partnerships, societies, and joint stock companies,
as well as individuals.”113 Courts have looked to the statute to construe federal criminal cases.114
Moreover, federal law now generally holds that corporations are criminally liable for crimes
committed by their officers, employees, or agents within the scope of their employment and for
the benefit of the corporation,115 although at common law corporations could not be thus held
criminally liable.116
Knowingly
Section 2339B has two knowledge elements.117 The government must prove that the defendant
knew that he was providing something to an entity (“whoever knowingly provides material
support or resources to a foreign terrorist organization”).118 It must also show that the defendant
knew that the entity was a designated terrorist organization or that the entity engaged in terrorism
or terrorist activity.119 The government does not have to demonstrate that the defendant “intended
to further a foreign terrorist organization’s illegal activities.”120

111 18 U.S.C. § 2339B(a)(1).
112 See generally CRS Report R43293, Corporate Criminal Liability: An Overview of Federal Law, by Charles Doyle.
113 1 U.S.C. § 1.
114 See, e.g., United States v. A & P Trucking Co., 358 U.S. 121, 123 (1958); United States v. Polizzi, 500 F.2d 856,
907 (9th Cir. 1974); United States v. George, 946 F.3d 643, 647 (4th Cir. 2020) (“Congress drafted the identity theft
statutes using the term ‘person’ which the Dictionary Act defines as . . . ”); United States v. Ruzicka, 331 F. Supp. 3d
888, 893 n.2 (D. Minn. 2018) (“While the CVRA [Crime Victims’ Rights Act] does not define ‘person,’ the Dictionary
Act defines ‘person’ to include both individuals and corporations.”).
115 United States v. Agosto-Vega, 617 F.3d 541, 552–53 (1st Cir. 2010); United States v. Singh, 518 F.3d 236, 249–50
(4th Cir. 2008).
116 I WILLIAM BLACKSTONE, COMMENTARIES 464 (1765) (“A corporation cannot commit treason, or felony, or other
crime, in its corporate capacity: though its members may, in their distinct individual capacities”) (transliteration
provided).
117 United States v. Al Kassar, 660 F.3d 108, 129 (2d Cir. 2011).
118 18 U.S.C. § 2339B(a)(1); Al Kassar, 660 F.3d at 129; United States v. Farah, 899 F.3d 608, 616 (8th Cir. 2018) (“A
defendant must generally know the facts that make his conduct illegal.”); United States v. Nagi, 254 F. Supp. 3d 548,
556 (W.D.N.Y. 2017) (“To obtain a conviction under § 2339B(a)(1), the Government must also prove that the person
‘ha[d] knowledge that the organization is a designated terrorist organization . . . , that the organization has engaged or
engages in terrorist activity . . . , or that the organization has engaged or engages in terrorism.’” (alterations in original)
(quoting Holder v. Humanitarian L. Project, 561 U.S. 1, 35 (2010)).
119 United States v. Wright, 937 F.3d 8, 23 (1st Cir. 2019) (“[T]o prove a violation of [§ 2339B], the government must
establish that a defendant (1) knowingly provided or attempted or conspired to provide material support . . . (3) that the
defendant knew had been designated a foreign terrorist organization or had engaged in terrorism.” (first and second
alterations in original) (emphasis added) (quoting United States v. Dhirane, 896 F.3d 295, 303 (4th Cir. 2018)); Al
Kassar
, 660 F.3d at 129; see also United States v. Omar, 786 F.3d 1104, 1112–13 (8th Cir. 2015); United States v.
Mehanna, 735 F.3d 32, 42 (1st Cir. 2013).
120 Holder v. Humanitarian Law Project, 561 U.S. 1, 16 (2010); Mehanna, 735 F.3d at 42; Al Kassar, 660 F.3d at 129.
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Provides
Here too, the law is much the same as in § 2339A. When neither a statute’s text, its context, nor
its legislative history suggest otherwise, Congress is thought to have intended common words to
have their common meaning.121 The word “provide” ordinarily means “to supply something for
sustenance or support.”122 Section 2339B has no explicit definition of the word “provide.”
Nothing in the context shows Congress intended to attach any special meaning to the word. The
legislative history is equally barren.123 When the Supreme Court dissected § 2339B in
Humanitarian Law Project, it passed by the word without comment.124 At least two lower federal
courts construing the word “provide” in § 2339B’s companion, § 2339A, concluded that the word
should be given its ordinary dictionary meaning.125
Material Support
The precise scope of the term “material support or resources” under § 2339B proved controversial
at first. With the addition from § 2339B(h) covering “personnel,” the section uses the definition in
§ 2339A(b) and thus covers “any property, tangible or intangible, or service.”126 The material
support excludes medicine and religious materials, but includes
• currency or monetary instruments or financial securities,
• financial services,
• lodging,
• training (i.e., instruction or teaching designed to impart a specific skill, as
opposed to general knowledge),
• expert advice or assistance (i.e., advice or assistance derived from scientific,
technical, or other specialized knowledge),
• safe houses,
• false documentation or identification,
• communications equipment, facilities,
• weapons,

121 Food Mktg. Inst. v. Argus Leader Media, 139 S. Ct. 2356, 2362 (2019) (“But FOIA nowhere defines the term
‘confidential.’ So, as usual, we ask what that term’s ‘ordinary, contemporary, common meaning’ was when Congress
enacted FOIA in 1966.” (quoting Perrin v. United States, 444 U.S. 37, 42 (1979)); Wis. Cent. Ltd. v. United States, 138
S. Ct. 2067, 2072 (2018); Sandifer v. U.S. Steel Corp., 571 U.S. 220, 227 (2014)) (“[U]nless otherwise defined, words
will be interpreted as taking their ordinary, contemporary, common meaning” (quoting Perrin, 444 U.S. at 42));
Taniguchi v. Kan Pac. Saipan, Ltd., 566 U.S. 560, 566 (2012) (“When a term goes undefined in a statute, we give the
term its ordinary meaning.”).
122 Provide, MERRIAM-WEBSTER’S COLLEGIATE DICTIONARY (10th ed. 2002).
123 The House Judiciary Committee report’s summary of the provision which ultimately became § 2339B does use
provide’s ordinary synonym, “supply,” perhaps offering some minimal credibility to the contention that the word
“provide” has its ordinary meaning: H.R. REP. NO. 104-383 at 81 (“Allowing an individual to supply funds, goods, or
services to an organization . . . helps defray the cost to the terrorist organization . . . .” (emphasis added)).
124 The Court in Humanitarian Law Project does point to the dictionary for the meaning of other words in the section,
561 U.S. at 23–24 (“‘[S]ervice’ similarly refers to concerted activity, not independent advocacy. See Webster’s Third
New International Dictionary 2075 (1993) (defining ‘service’ . . . .)”).
125 United States v. Sattar, 314 F. Supp. 2d 279, 297 (S.D.N.Y. 2004); United States v. Abu-Jihaad, 600 F. Supp. 2d
362, 399–400 (D. Conn. 2009).
126 18 U.S.C. § 2339B(g)(4).
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• lethal substances,
• explosives,
• personnel (one or more individuals who may be or include oneself), and
• transportation.127
Section 2339B adopts § 2339A’s definition of “material support,” and its accompanying
definitions of “training” and “expert advice and assistance.”128 Section 2339B also supplies two
amplifications of the word “personnel.” One limits the word to those working under the direction
of a designated terrorist organization.129 The other provides limited immunity from prosecution
for those who provide support with the approval of the Secretary of State and the Attorney
General.130
Congress adjusted some of the definitions in the wake of First Amendment overbreadth and due
process vagueness challenges that the Supreme Court ultimately addressed in Holder v.
Humanitarian Law Project
.131 The Humanitarian Law Project and other groups had argued that §
2339B’s prohibitions against providing “personnel” or “training” were unconstitutionally vague
and might extend to things like advocating the organizations’ interests before the U.N.
Commission on Human Rights; petitioning Members of Congress on their behalf, seeking the
release of political prisoners; or training the organizations’ members on the use of international
law to resolve political disputes peacefully.132 In Humanitarian Law Project, the Supreme Court
held that § 2339B, as applied, was not unconstitutionally vague; did not constitute an abridgement
of the First Amendment right to free speech; and did not impermissibly intrude on the right of
free association.133
Chief Justice Roberts, writing for the six-member majority, noted early on that the lower court
had interwoven First Amendment overbreadth into its due process vagueness analysis, and he
explained that in both respects it had “contravened the rule that ‘[a] plaintiff who engages in some

127 Id. § 2339A(b).
128 Id. § 2339B(g)(4).
129 Id. § 2339B(h) (“No person may be prosecuted under this section in connection with the term ‘personnel’ unless that
person has knowingly provided, attempted to provide, or conspired to provide a foreign terrorist organization with 1 or
more individuals (who may be or include himself) to work under that terrorist organization’s direction or control or to
organize, manage, supervise, or otherwise direct the operation of that organization. Individuals who act entirely
independently of the foreign terrorist organization to advance its goals or objectives shall not be considered to be
working under the foreign terrorist organization’s direction and control”); United States v. Hendricks, 950 F.3d 348,
353 (6th Cir. 2020) (“[H]e contends only that the government failed to present evidence from which a jury could find
that he agreed or intended to [act] on behalf of ISIS. That argument, however, ignores evidence from which a jury
could reasonably infer that Hendricks (1) communicated with and took direction from ISIS members, (2) viewed
himself and his recruits as agents of ISIS, and (3) acted in a manner consistent with someone who was operating or
seeking to operate on behalf of ISIS.”).
130 18 U.S.C. § 2339B(i) (“No person may be prosecuted under this section in connection with the term ‘personnel’,
‘training’, or ‘expert advice or assistance’ if the provision of that material support or resources to a foreign terrorist
organization was approved by the Secretary of State with the concurrence of the Attorney General. The Secretary of
State may not approve the provision of any material support that may be used to carry out terrorist activity (as defined
in section 212(a)(3)(B)(iii) of the Immigration and Nationality Act”).
131 561 U.S. 1 (2010).
132 Humanitarian Law Project v. Reno, 9 F. Supp. 2d 1176, 1203–04 (C.D. Cal. 1998).
133 Humanitarian Law Project 561 U.S. at 8. For a discussion of the case and others in an Internet context, see CRS
Report R45713, Terrorism, Extremism, and the Internet, by Victoria L. Killion.
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conduct that is clearly proscribed cannot complain of the vagueness of the law as applied to the
conduct of others.’”134
The Chief Justice pointed out that due process bars enforcing a vague criminal statute. A statute is
impermissibly vague when it “‘fails to provide a person of ordinary intelligence fair notice of
what is prohibited, or is so standardless that it authorizes or encourages seriously discriminatory
enforcement.’”135 When a statute clearly applies to the conduct at issue, it is to no avail that its
application may be unclear under other circumstances.136
Section 2339B is not unconstitutionally vague as applied to the type of support at issue –
coordinated advocacy on behalf of a terrorist organization and training the organization’s
members to use international law to resolve disputes and to petition the United Nations and other
similar entities for relief, Chief Justice Roberts observed.137 A reasonable person would realize
that this training constitutes providing “‘expert advice or assistance’ . . . derived from . . .
‘specialized knowledge,’” and that this advocacy, when coordinated or directed by a terrorist
organization, constitutes providing a service to such an organization.138
As for free speech, the Chief Justice concluded that Congress may outlaw material support to a
terrorist organization in the form of speech of the type at issue without offending the First
Amendment. The government has a compelling interest in the suppression of terrorism. Training
and coordinated support in the form of advocacy of a terrorist organization’s lawful activities
frees resources to service illicit activities; lends legitimacy to the organization; and may strain
diplomatic relations with the countries against whom the organization’s terrorist activities may be
directed.139 In this case, “[a] foreign terrorist organization introduced to the structures of the
international legal system might use the information to threaten, manipulate, and disrupt.”140 An
organization guide to and through the avenues to international relief might secure relief in the
form of fungible monetary aid.141
The Chief Justice disposed of the groups’ freedom of association argument with the notation that
the section outlaws conduct, not membership.142
Terrorist Organizations
Providing material support is only a crime under § 2339B if the known beneficiary is a foreign
terrorist organization. That is, the government must show either that (1) the defendant knows that
the organization has been designated a foreign terrorist organization or (2) the defendant knows
that the organization is or has engaged in “terrorism” or in “terrorist activities.”143

134 Humanitarian Law Project 561 U.S. at 20 (quoting Hoffman Estates v. Flipside, Hoffman Estates, Inc., 455 U.S.
489, 495 (1982)).
135 Id. at 18 (quoting United States v. Williams, 553 U.S. 285, 304 (2008)).
136 Id. at 18–19 (citing Hoffman Estates, 455 U.S. at 495).
137 Id. at 22.
138 Id.
139 Id. at 33–8.
140 Id. at 37.
141 Id.
142 Id. at 39.
143 18 U.S.C. § 2339B(a); United States v. Farah, 899 F.3d 608, 616 (8th Cir. 2018) (“A defendant must generally know
the facts that make his conduct illegal.”); United States v. Nagi, 254 F. Supp. 3d 548, 556 (W.D.N.Y. 2017) (“To obtain
a conviction under § 2339B(a)(1), the Government must also prove that the person had knowledge that the organization
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Designated Terrorist Organizations
The process under which the Secretary of State designates an entity a foreign terrorist
organization is authorized in section 219 of the Immigration and Nationality Act.144 Under the
procedure, the Secretary may designate an entity if he finds that it is (A) a foreign organization;
(B) that “engages in terrorist activity or terrorism, or retains the capacity and intent to engage in
terrorist activity or terrorism”; and (C) “the terrorist activity or terrorism” of the entity “threatens
the security of United States nationals or the national security of the United States.”145 An
organization may challenge its designation,146 and the Secretary may revoke the designation.147
The organization may appeal the Secretary’s decision to the United States Court of Appeals for
the District of Columbia.148
A defendant, charged with providing material support to an organization, however, may not
challenge the designation.149 The courts have consistently held that a defendant’s inability to
challenge the designation does not offend due process; nor does it constitute an unconstitutional
delegation of legislative authority.150
Organizations Engaged in Terrorism or Terrorist Activities
Organizations that the accused knew engaged in “terrorism” or “engaged in terrorist activities”
constitute a second class of banned beneficiaries. “Terrorism” under § 2339B is simply
“premeditated, politically motivated violence perpetrated against noncombatant targets by
subnational groups or clandestine agents.”151 The definition of an organization that “engages in
terrorist activities” is more multi-faceted as noted in the margin.152

is a designated terrorist organization . . . , that the organization has engaged or is engaged in terrorist activity . . . , or
that the organization has engaged or engages in terrorism.”).
144 8 U.S.C. § 1189.
145 8 U.S.C. § 1189(a)(1).
146 8 U.S.C. § 1189(a)(4)(B).
147 8 U.S.C. § 1189(a)(6).
148 8 U.S.C. § 1189(c).
149 8 U.S.C. § 1189(a)(8); United States v. Afshari, 426 F.3d 1150, 1155–59 (D.C. Cir. 2005); United States v.
Hammoud, 381 F.3d 316, 331 (4th Cir. 2004), vacated, 543 U.S. 1097 (2005), opinion reinstated in part, 405 F.3d
1034 (2005) (en banc).
150 Ali, 799 F.3d at 1119–20 (“Congress may delegate its legislative power if it ‘lay[s] down by legislative act an
intelligible principle to which the person or body authorized to [act] is directed to conform.’” . . . The statutory scheme
governing the designation of foreign terrorist organizations provides an intelligible principle. . . . [T]he statute permits
the Secretary to make a designation only after making three discrete findings.” (first and third alterations in original)
(quoting South Dakota v. U.S. Dep’t of Interior, 423 F.3d 790, 795 (8th Cir. 2005) (citing in accord Hammoud, 381
F.3d at 331; United States v. Taleb-Jedi, 566 F. Supp. 2d 157, 172–73 (E.D.N.Y. 2008)).
151 “Terrorism” is defined by cross reference to Section 140(d)(2) of the Foreign Relations Authorization Act, Fiscal
Years 1988 and 1989, Pub. L. 100-204, 101 STAT. 1349 (1987), codified at 22 U.S.C. § 2656(f)(d)(2).
152 For purposes of § 2339B, the term “engage in terrorist activity” is defined by cross reference to § 212(a)(3)(B), 8
U.S.C. § 1182(a)(3)(B), of the Immigration and Nationality Act, which defines the term in subparagraph (iv) (“the term
‘engage in terrorist activity’ means, in an individual capacity or as a member of an organization – (I) to commit or to
incite to commit, under circumstances indicating an intention to cause death or serious bodily injury, a terrorist activity;
(II) to prepare or plan a terrorist activity; (III) to gather information on potential targets for terrorist activity; (IV) to
solicit funds or other things of value for - (aa) a terrorist activity; (bb) a terrorist organization described in clause (vi)(I)
or (vi)(II); or (cc) a terrorist organization described in clause (vi)(III), unless the solicitor can demonstrate by clear and
convincing evidence that he did not know, and should not reasonably have known, that the organization was a terrorist
organization; (V) to solicit any individual – (aa) to engage in conduct otherwise described in this subsection; (bb) for
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In the Immigration and Nationality Act, and thus under § 2339B, “the term ‘terrorist activity’
means any activity unlawful under the laws of the place where it is committed (or which, if it had
been committed in the United States, would be unlawful under the laws of the United States or
any State) and which involves any of the following:
(I) The highjacking or sabotage of any conveyance (including an aircraft, vessel, or vehicle).
(II) The seizing or detaining, and threatening to kill, injure, or continue to detain, another
individual in order to compel a third person (including a governmental organization) to do or
abstain from doing any act as an explicit or implicit condition for the release of the individual
seized or detained.
(III) A violent attack upon an internationally protected person (as defined in Section
1116(b)(4) of Title 18) or upon the liberty of such a person.
(IV) An assassination.
(V) The use of any –
(a) biological agent, chemical agent, or nuclear weapon or device, or
(b) explosive, firearm, or other weapon or dangerous device (other than for mere personal
monetary gain), with intent to endanger, directly or indirectly, the safety of one or more
individuals or to cause substantial damage to property.
(VI) A threat, attempt, or conspiracy to do any of the foregoing.153
Attempt, Conspiracy, Aiding and Abetting
Section 2339B outlaws both attempts and conspiracies to violate its substantive provisions.154 In
general, attempt is the unfulfilled commission of an underlying offense. As noted earlier, if the
attempt succeeds, the offender cannot be prosecuted or punished for both the completed offense
and the attempt to commit it.155 “Attempt” has two elements: (1) an intent to commit the
underlying offense; and (2) some substantial step towards its completion.156 Mere preparation is

membership in a terrorist organization described in clause (vi)(I) or (vi)(II); or (cc) for membership in a terrorist
organization described in clause (vi)(III) unless the solicitor can demonstrate by clear and convincing evidence that he
did not know, and should not reasonably have known, that the organization was a terrorist organization; or (VI) to
commit an act that the actor knows, or reasonably should know, affords material support, including a safe house,
transportation, communications, funds, transfer of funds or other material financial benefit, false documentation or
identification, weapons (including chemical, biological, or radiological weapons), explosives, or training – (aa) for the
commission of a terrorist activity; (bb) to any individual who the actor knows, or reasonably should know, has
committed or plans to commit a terrorist activity; (cc) to a terrorist organization described in subclause (I) or (II) of
clause (vi) or to any member of such an organization; or (dd) to a terrorist organization described in clause (vi)(III), or
to any member of such an organization, unless the actor can demonstrate by clear and convincing evidence that the
actor did not know, and should not reasonably have known, that the organization was a terrorist organization.”).
153 “Terrorist activity” is defined by cross reference to § 212(a)(3)(B), 8 U.S.C. § 1182(a)(3)(B), of the Immigration
and Nationality Act, which defines the term in subparagraph (iii).
154 18 U.S.C. § 2339B(a)(1).
155 United States v. Rivera-Relle, 333 F.3d 914, 921–22 n.11 (9th Cir. 2003); see generally CRS Report R42001,
Attempt: An Overview of Federal Criminal Law, by Charles Doyle.
156 United States v. Pugh, 945 F.3d 9, 20 (2d Cir. 2019) (“‘In order to establish that a defendant is guilty of an attempt
to commit a crime, the government must prove that the defendant had the intent to commit the crime and engaged in
conduct amounting to a substantial step towards the commission of the crime.’ . . . For purposes of the statute under
which Pugh was charged, ‘a substantial step towards the provision of material support need not be planned to culminate
in actual terrorist harm, but only in support – even benign support – for an organization committed to such harm.’”
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not enough.157 “To constitute a substantial step, a defendant’s actions must cross the line between
preparation and attempt by unequivocally demonstrating that the crime will take place unless
interrupted by independent circumstances.”158 It is no defense that, unbeknownst to the defendant,
commission of the underlying offense was impossible, as for example because he was dealing
with government undercover agents rather than agents of a foreign terrorist organization.159 An
attempt to provide material support in violation of § 2339B and providing the assistance are
punished the same: imprisonment for not more than 20 years (for any term of years or life, if
death results from the commission of the offense), or a fine of not more than $250,000 (not more
than $500,000 for an organization) (or not more than twice the amount of gain or loss associated
with the offense), or imprisonment and a fine.160
Conspiracy to provide material support in violation of § 2339B is the agreement to provide such
support.161 The offense is complete upon assent; the support need be agreed only to, not
delivered.162 Moreover, each of the conspirators is liable not only for the conspiracy, but for any
other foreseeable offense committed by any of the conspirators in furtherance of the overall
scheme.163 Like attempt, conspiracy to provide material support carries the same penalties as the
completed substantive offense: imprisonment for not more than 20 years (for any term of years or
life, if death results from the commission of the offense), or a fine of not more than $250,000 (not
more than $500,000 for an organization) (or not more than twice the amount of gain or loss
associated with the offense), or imprisonment and a fine.164 Unlike attempt, conspirators may be

(first quoting United States v. Yousef, 327 F.3d 56, 134 (2d Cir. 2003; and then quoting United States v. Farhane, 634
F.3d 127, 148 (2d Cir. 2011)); see generally Braxton v. United States, 500 U.S. 344, 349 (1991); United States v.
Hendricks, 950 F.3d 348, 353 (6th 2020) (“Hendricks does not contend that he lacked the requisite intent or common
purpose to form and operate a terrorist cell. Nor does he contend that he failed to take a substantial step toward
engaging in such activity.”); United States v. Suarez, 893 F.3d 1330, 1335 (11th Cir. 2018); United States v. Nguyen,
829 F.3d 907, 918 (8th Cir. 2016); Farhane, 634 F.3d at 145; cf. United States v. Mehanna, 735 F.3d 32, 53 (1st Cir.
2013).
157 Pugh, 945 F.3d at 20; see generally United States v. Alebbini, 979 F.3d 537, 546–47 (6th Cir.2020); United States v.
Faust, 795 F.3d 1243, 1248 (10th Cir. 2015); United States v. Aldawsari, 740 F.3d 1015, 1019–20 (5th Cir. 2014).
158 United States v. Mincoff, 574 F.3d 1186, 1195 (9th Cir. 2009); see also United States v. Muratovic, 719 F.3d 809,
815 (7th Cir. 2013); United States v. Irving, 665 F.3d 1184, 1196 (10th Cir. 2011).
159 United States v. Rehak, 589 F.3d 965, 970–71 (8th Cir. 2009); see also Mehanna, 735 F.3d at 53; United States v.
Coté, 504 F.3d 682, 687 (7th Cir. 2007); cf. United States v. Lakhani, 480 F.3d 171, 174–77 (3d Cir. 2007).
160 18 U.S.C. §§ 2339B(a), 3571.
161 See generally United States v. Jimenez Recio, 537 U.S. 270, 274 (2003) (“[T]he essence of a conspiracy is an
‘agreement to commit an unlawful act.’” (quoting Iannelli v. United States, 420 U.S. 770, 777 (1994))); United States
v. Flores, 945 F.3d 687, 712 (2d Cir. 2019) (“The crux of a conspiracy is an agreement between two or more persons to
join together to accomplish something illegal.” (quoting United States v. Lyle, 919 F.3d 716, 737 (2d Cir. 2019)));
United States v. Orlando, 819 F.3d 1016, 1022 (7th Cir. 2016) (“To convict a defendant of conspiracy, the government
prove beyond a reasonable doubt that the defendant knowingly and intentionally joined in an agreement with one or
more other individuals to commit an unlawful act.”); United States v. Morris, 817 F.3d 1116, 1119 (8th Cir. 2016);
United States v. Valle, 807 F.3d 508, 515–16 (2d Cir. 2015)).
162 United States v. Salahuddin, 765 F.3d 329, 341 (3d Cir. 2014); United States v. Vallone, 752 F.3d 690, 697–98 (7th
Cir. 2014); United States v. Torres-Vázquez, 731 F.3d 41, 45 (1st Cir. 2013); United States v. Rehak, 589 F.3d 965,
971 (8th Cir. 2009); United States v. Moalin, 973 F.3d 977, 1006–07 (9th Cir. 2020) (“None of the three conspiracy
counts [under § 2339A and § 2339B] required the prosecution to prove that Doreh committed an overt act in
furtherance of the conspiracy.”).
163 Pinkerton v. United States, 328 U.S. 640, 647 (1946); United States v. Denton, 944 F.3d 170, 179 (4th Cir. 2019);
United States v. Baker, 923 F.3d 390, 406 (5th Cir. 2019); United States v. Amawi, 695 F.3d 457, 499 (6th Cir. 2012)
(Moore, J., concurring).
164 18 U.S.C. §§ 2339B(a), 3571.
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punished for both conspiracy and for providing material support should the scheme to provide it
succeed.165
Under 18 U.S.C. § 2, anyone who counsels, procures, aids, or abets a violation of § 2339B or any
other federal crime is punishable as though he had committed the offense himself.166 “In order to
aid and abet another to commit a crime it is necessary that a defendant in some sort associate
himself with the venture, that he participate in it as in something that he wishes to bring about,
[and] that he seek by his action to make it succeed.”167 “Typically, the same evidence will support
both a conspiracy and an aiding and abetting conviction.”168 A completed offense is a prerequisite
to conviction for aiding and abetting, but the hands-on offender need be neither named nor
convicted.169
Consequences of Charge or Conviction
Conviction for a violation of § 2339B is punishable by imprisonment for not more than 20 years
(for any period of years or for life if death results from commission of the offense) or a fine of not
more than $250,000 (not more than $500,000 for an organizational defendant), or both
imprisonment and a fine.170 The Sentencing Guidelines assign a base offense level of 26 which
translates, without more, to a sentencing range of 63 to 78 months imprisonment for offenders

165 Iannelli v. United States, 420 U.S. 770, 777–78 (1975); United States v. George, 886 F.3d 31, 41 (1st Cir, 2018);
United States v. Chandia, 514 F.3d 365, 372 (4th Cir. 2008) (“We also disagree with Chandia’s argument that Congress
did not intend to authorize multiple punishments for a conspiracy and a substantive violation under § 2339B. Chandia’s
argument is based on the language of the statute, which prohibits the conspiracy and the actual provision of material
support in the same section. See 18 U.S.C. § 2339B(a)(1). (‘Whoever knowingly provides material support . . . or
attempts or conspires to do so . . . ’).” (alterations in original)). But, as the Supreme Court has held, the ‘settled
principle’ that “‘the commission of the substantive offense and a conspiracy to commit it are separate and distinct
offenses’” does not give way simply because the statute describing the substantive offense also specifically prohibits
conspiracies. Callanan v. United States, 364 U.S. 587, 593 (1961) (quoting Pinkerton, 328 U.S. at 643).
166 In re Colon, 826 F.3d 1301, 1305 (11th Cir. 2016); see generally CRS Report R43769, Aiding, Abetting, and the
Like: An Overview of 18 U.S.C. § 2
, by Charles Doyle.
167 Nye & Nissen v. United States, 336 U.S. 613, 619 (1949); see also Rosemond v. United States, 572 U.S. 65, 71
(2014) (“As at common law, a person is liable under § 2 for aiding and abetting a crime if (and only if) he (1) takes an
affirmative act in furtherance of that offense, (2) with the intent of facilitating the offense’s commission.”); United
States v. Tanco-Baez, 942 F.3d 7, 27 (1st Cir. 2019); United States v. Daniels, 930 F.3d 393, 403 (5th Cir. 2019);
United States v. Brown, 929 F.3d 1030, 1039 (8th Cir. 2019); see also United States v. Sineneng-Smith, 910 F.3d 461,
482 (9th Cir. 2018) (“‘[T]he elements necessary for an aiding and abetting conviction are: (1) that the accused had the
specific intent to facilitate the commission of a crime by another, (2) that the accused had the requisite intent of the
underlying substantive offense, (3) that the accused assisted or participated in the commission of the underlying
substantive offense, and (4) that someone committed the underlying substantive offense.’” (quoting United States v.
Thum, 749 F.3d 1143, 1148–49 (9th Cir. 2014)), vacated and remanded on other grounds, 140 S. Ct. 1575 (2020);
United States v. Little, 829 F.3d 1177, 1184 (10th Cir. 2016).
168 United States v. Vasquez, 677 F.3d 685, 695 (5th Cir. 2012); see also United States v. Boria, 592 F.3d 476, 481 n.8
(3d Cir. 2010).
169 United States v. Bowens, 907 F.3d 347, 351 (5th Cir. 2018); United States v. Litwok, 678 F.3d 208, 213 n.1 (2d Cir.
2012) (“The Government never clearly identified whom Litwok aided and abetted in this fraud. [Yet,] ‘[t]o show a
violation of 18 U.S.C. § 2 it is not necessary to identify any principal at all, provided the proof shows that the
underlying crime was committed by someone.’” (quoting United States v. Perry, 643 F.2d 38, 45 (2d Cir. 1981));
United States v. Mullins, 613 F.3d 1273, 1290 (10th Cir. 2010) (“It is not even essential that the identity of the
principal be established. The prosecution only need prove that the offense has been committed.” (quoting United States
v. Harper, 579 F.2d 1235, 1239 (10th Cir. 1978)).
170 18 U.S.C. §§ 2339B(a)(1), 3571(b), (c). Congress increased the maximum term of imprisonment from 15 to 20 years
in 2015, USA FREEDOM Act of 2015, Pub. L. No. 114-23, § 704, 129 STAT. 300.
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with a virtually pristine criminal record.171 Section 2339B offenses, however, like those of
§ 2339A, may trigger the Guidelines’ terrorism adjustment.172
Section 3A1.4 of the Guidelines raises the offense level to 32 and the criminal history to category
VI, which applies when the offense “involved or was intended to promote, a federal crime of
terrorism” and which translates to a sentencing range of 210 to 262 months in prison.173 A
“federal crime of terrorism” is any of the offenses listed in § 2332b(g)(5)(B) and “calculated to
influence or affect the conduct of government by intimidation or coercion, or to retaliate against
government conduct.”174 It requires “that the underlying felony,” the triggering crime of terrorism,
“[be] calculated to influence or affect the conduct of government by intimidation or coercion, or
to retaliate against government conduct.”175
Constitutional challenges to § 3A1.4, arguing the adjustment violates the Eighth Amendment
prohibition on cruel and unusual punishment176 or the Sixth Amendment right to a jury trial or the
Fifth Amendment right to due process, 177 have yet to prevail.
Sentencing courts may depart from the sentencing range recommended by the Guidelines,178 but
are subject to review if the sentence they impose is procedurally or substantively unreasonable.179
A sentence is procedurally unreasonable, among other things, if it results from a Guideline
miscalculation.180 A sentence is substantively unreasonable, if it is unduly lenient or unduly
severe based on the nature and severity of the offense and the defendant’s circumstances.181

171 U.S. SENT’G GUIDELINES MANUAL § 2M5.3 (U.S. SENT’G COMM’N 2021); id. Sentencing Table.
172 U.S.S.G § 3.A1.4 (“(a) If the offense is a felony that involved, or was intended to promote, a federal crime of
terrorism, increase by 12 levels; but if the resulting offense level is less than level 32, increase to level 32. (b) In each
such case, the defendant’s criminal history category from Chapter Four . . . shall be Category VI.”); id. § 3A1.4, cmt.
app. n.1 (“For purposes of this guideline, ‘federal crime of terrorism’ has the meaning given that term in 18 U.S.C.
§ 2332b(g)(5).”). Section 2332b(g)(5) states, “the term ‘Federal crime of terrorism’ means an offense that -- (A) is
calculated to influence or affect the conduct of government by intimidation or coercion, or to retaliate against
government conduct; and (B) is a violation of – (i) section . . . 2339A (relating to providing material support to
terrorists), 2339B (relating to providing material support to terrorist organizations) . . . of this title . . .”).
173 U.S. SENT’G GUIDELINES MANUAL, Sentencing Table.
174 18 U.S.C. § 2332b(g)(5)(A).
175 United States v. Alhaggagi, 978 F.3d 693, 700 (9th Cir. 2020) (quoting United States v. Stewart, 590 F.3d 93, 138
(2d Cir. 2009); see also United States v. Arcila Ramrez, 16 F.4th 844, 852–55 (11th Cir. 2021); United States v.
Khatallah, 41 F.4th 608, 646 (D.C. Cir. 2022).
176 United States v. Suarez, 893 F.3d 1330, 1335 (11th Cir. 2018).
177 United States v. Ali, 799 F.3d 1008, 1030-31 (8th Cir. 2015) (citing United States v. Meskini, 319 F.3d 88, 92 (2d
Cir. 2003) with regard to the due process contention); United States v. Khan, 938 F.3d 713, 717 (5th Cir. 2019); United
States v. Abu Khatallah, 314 F. Supp. 3d 179, 197 (D.D.C. 2018) (“So long as a defendant’s sentence is within the
range prescribed by statute, the use of judge-found facts to arrive at that sentence ‘does not implicate the Sixth
Amendment.’ Nor does that practice violate the Due Process Clause of the Fifth Amendment.” (quoting United States
v. Jones, 744 F.3d 1362, 1379 (D.C. Cir. 2014)).
178 United States v. Kabir, 51 F.4th 820, 828 (9th Cir. 2022).
179 Gall v. United States, 552 U.S. 38, 51 (2007); e.g., United States v. Kourani, 6 F.4th 345, 356–58 (2d Cir. 2021).
180 Gall, 552 U.S. at 51; see also United States v. Pugh, 945 F.3d 9, 24–25 (2d Cir. 2019) (“[A] sentencing judge
‘should begin all sentencing proceedings by correctly calculating the applicable [Sentencing] Guidelines range.’ In
addition, before imposing a sentence, the district court has an obligation to weigh all the factors listed in section
3553(a). . . . Violation of the duties to correctly calculate the Guidelines, to consider the section 3553(a) factors, and to
state the reasons for the particular sentence imposed can all give rise to an appellate determination of procedural
unreasonableness.” (citation omitted) (quoting Gall, 552 U.S. at 49)); Khan, 938 F.3d at 717–18; United States v.
Hammadi, 737 F.3d 1043, 1047 (6th Cir. 2013).
181 Gall, 552 U.S. at 51; see also United States v. Ceasar, 10 F.4th 66, 70 (2d Cir. 2021) (vacating a 48-month sentence
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Federal Crime of Terrorism
Section 2339B violations constitute federal crimes of terrorism if they are “calculated to influence
or affect the conduct of government by intimidation or coercion, or to retaliate against
government conduct.”182 Classification as a federal crime of terrorism has several consequences.
Property derived from, involved in, or used in, the commission of such an offense committed
against the United States or any of its nationals is subject to confiscation.183 Federal crimes of
terrorism are by definition predicate offenses under federal money laundering and RICO
prosecutions.184 Prosecution of a § 2339B offense is subject to an eight-year statute of limitations,
rather than the general five-year period.185 An accused charged with a violation of a federal crime
of terrorism faces an enhanced prospect of pre-trial detention.186 A defendant convicted for
violating a federal crime of terrorism faces a possible life-time term of supervised release, rather
than the general five-year maximum term.187

as “shockingly low” following conviction for conspiracy to violate § 2339B); United States v. Khan, 997 F.3d 242, 248
(5th Cir. 2021) (reversing as substantively unreasonable an 18-month sentence following conviction for violation of §
2339B); United States v. Mumuni, 946 F.3d 97, 107 (2d Cir. 2019) (“In sum, in reviewing a sentence for substantive
reasonableness, we are . . . ‘concluding, after careful review, (1) that a sentence lacks a proper basis in the record, (2)
that a trial judge’s assessment of the evidence leaves the reviewing court with a definite and firm conviction that a
mistake has been committed, or (3) that the reviewing court has reached the informed judgment that a sentence is
otherwise unsupportable as a matter of law.’” (quoting United States v. Park, 758 F.3d 193, 200–01 (per curiam))
(holding that a 17-year prison term for attempting to kill a federal officer and providing material support to a
designated foreign terrorist organization was substantively unreasonable in light of the serious nature of the defendant’s
conduct)); Suarez, 893 F.3d at 1337; Hammadi, 737 F.3d at 1047 (“[W]e examine the substantive reasonableness of the
sentence, reversing if the § 3553(a) factors considered together do not justify the sentence imposed.”); Ali, 799 F.3d at
1033 (A court imposes a substantively “unreasonable sentence ‘when it fails to consider a relevant and significant
factor, gives significant weight to an irrelevant or improper factor, or considers the appropriate factors but commits a
clear error of judgment in weighing those factors.’ However, when a district court varies downward from the advisory
sentencing guidelines range . . . ‘it is nearly inconceivable that the court abused its discretion in not varying downward
still further.’” (first quoting United States v. Stong, 773 F.3d 920, 926 (8th Cir. 2014); and then quoting United States
v. Zauner, 688 F.3d 426, 429 (8th Cir. 2012)).
182 18 U.S.C. § 2332b(g)(5)(A),
183 18 U.S.C. § 981(a)(1)(G)(iii); see generally CRS Report 97-139, Crime and Forfeiture, by Charles Doyle.
184 18 U.S.C. §§ 1956(c)(7)(D), 1961(1)(G). Among other things, the federal racketeering statute prohibits conducting,
through the patterned commission of more than one predicate offense, the affairs of an enterprise whose activities affect
interstate or foreign commerce, 18 U.S.C. §§ 1962, 1961. The principal federal money laundering offenses include
engaging in a financial transaction involving the proceeds of a predicate offense that is designed to launder the
proceeds or to use them to promote further predicate offenses, 18 U.S.C. §§ 1956(a)(1), (c)(7). See generally CRS
Report 96-950, RICO: A Brief Sketch, by Charles Doyle, and CRS Report RL33315, Money Laundering: An Overview
of 18 U.S.C. § 1956 and Related Federal Criminal Law
, by Charles Doyle.
185 18 U.S.C. §§ 3286(a), 3282. Prosecution of a federal crime of terrorism may be brought at any time if the offenses
involve the risk of serious bodily injury. 18 U.S.C. § 3286(b).
186 18 U.S.C. §§ 3142(f)((1)(A), (g)(1); see e.g., United States v. Omar, 107 F. Supp. 3d 1008, 1009 (D. Minn. 2015)
(“Because the Defendant has been charged under 18 U.S.C. § 2339B, and because the Magistrate Judge found probable
cause exists to support these charges, there is a rebuttable presumption that no condition or combination of conditions
will reasonably assure the appearance of the Defendant and the safety of the community.” (Providing material support
or resources to designated foreign terrorist organizations is a crime listed in 18 U.S.C. § 2332b(g)(5)(i)); United States
v. Sheikh, 994 F. Supp. 2d 736, 739–41 (E.D.N.C. 2014); United States v. Salman, 241 F. Supp. 3d 1288, 1290–92
(M.D. Fla. 2017).
187 18 U.S.C. §§ 3583(j), (b). A term of supervised release is a period of time during which a defendant, having been
released from prison, is subject to the supervision of the Probation Service and a number of conditions which may
restrict his travel, employment, associations, or use of the Internet, among other things, 18 U.S.C. §§ 3583(c), (d); see
generally
CRS Report RL31653, Supervised Release (Parole): An Overview of Federal Law, by Charles Doyle.
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Extraterritorial Jurisdiction
In general, federal criminal law is territorial—that is, it applies only to conduct within the
territory of the United States—unless Congress signifies otherwise.188 Congress has used one of
two methods to signal overseas application of a criminal statute. In some cases, the statute states
in general terms, without more, that it has extraterritorial application.189 In others, it describes the
circumstances under which it reaches offenses committed overseas.190
Section 2339B has both a general statement of extraterritorial jurisdiction (§ 2339B(d)(2)) and an
enumerating statement of extraterritorial jurisdiction (§ 2339B(d)(1)).191 The general statement
declares, “There is extraterritorial Federal jurisdiction over an offense under this section,”192 The
enumerating statement provides, “There is jurisdiction over an offense under subsection (a) if –
(A) an offender is a national of the United States . . . or an alien lawfully admitted for
permanent residence in the United States . . . ;
(B) an offender is a stateless person whose habitual residence is in the United States;
(C) after the conduct required for the offense occurs an offender is brought into or found in
the United States, even if the conduct required for the offense occurs outside the United
States;
(D) the offense occurs in whole or in part within the United States;
(E) the offense occurs in or affects [U.S.] interstate or foreign commerce; or
(F) an offender aids or abets any person over whom jurisdiction exists under this paragraph in
committing an offense under subsection (a) or conspires with any person over whom
jurisdiction exists under this paragraph to commit an offense under subsection (a).”193
The general statement has been part of the section since its inception.194 The enumerative
statement appeared as part of the Intelligence Reform and Terrorism Prevention Act of 2004.195
The legislative history of the 2004 legislation does not explain why the apparently overlapping
enumerative statement was thought necessary.196 Had the general statement been dropped at the
time, it would be clear Congress intended extraterritorial application to be confined to situations

188 Smith v. United States, 507 U.S. 197, 203 (1993); Small v. United States, 544 U.S. 385, 388–89 (2005); cf. RJR
Nabisco, Inc. v. European Community, 579 U.S. 325 (2016); see generally CRS Report 94-166, Extraterritorial
Application of American Criminal Law
, by Charles Doyle.
189 18 U.S.C. § 351(i) (crimes committed against Members of Congress) (“There is extraterritorial jurisdiction over the
conduct prohibited by this section”); 18 U.S.C. § 2381 (treason) (“Whoever . . . within the United States or elsewhere .
. . .”).
190 18 U.S.C. § 175(a) (relating to biological weapon offenses) (“There is extraterritorial Federal jurisdiction over an
offense under this section committed by or against a national of the United States”); 18 U.S.C. §1203(b)(1) (relating to
hostage taking) (“[I]t is not an offense under this section if the conduct required for the offense occurred outside the
United States unless – (A) the offender or the person seized or detained is a national of the United States; (B) the
offender is found in the United States; or (C) the governmental organization sought to be compelled is the Government
of the United States.”).
191 18 U.S.C. § 2339B(d)(1), (d)(2).
192 18 U.S.C. § 2339B(d)(2).
193 18 U.S.C. § 2339B(d)(1).
194 Antiterrorism and Effective Death Penalty Act of 1996, Pub. L. No. 104-132, § 303, 110 STAT. 1250 (codified at 18
U.S.C. § 2339B(d) (2000)).
195 Pub. L. No. 108-458, § 6603(d), 118 STAT. 3763 (2004).
196 H.R. Rep. No. 108-724, pt. V, at 172–73; pt. VI, at 173–74 (2004).
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in the enumerative statement. Including both suggests Congress may have intended
extraterritorial application in any situation that falls under either provision. Several district courts,
however, may have reached a different conclusion, although their explanations might be
attributable to the language of the indictments at issue.197
In response to the contention that § 2339B prosecutions violate due process constraints, some
courts have stated that “[f]or non-citizens acting entirely abroad, a [due-process-required]
jurisdictional nexus exists when the aim of that activity is to cause harm inside the United States
or to U.S. citizens or interests.”198
Civil Actions
Section 2339B(c) authorizes the Attorney General or the Secretary of the Treasury to bring a civil
suit in district court to enjoin violation of the section, but has yet to be the subject of any reported
case.
As with violations of § 2339A, § 2333 may provide victims of § 2339B with a cause of action for
triple damages and attorneys’ fees. “Any national of the United States[,] injured in his or her
person, property, or business by reason of an act of international terrorism[,]” may recover under
§ 2333.199 Acts of international terrorism consist of dangerous crimes, such as violations of
§ 2339B,200 apparently committed for terrorist purposes,201 and having some international
nexus.202

197 United States v. Ahmed, 94 F. Supp. 3d 394, 411 (E.D.N.Y. 2015) (“Defendants are mistaken that the statute has
‘boundless’ extraterritorial reach . . . [T]he statute includes an ‘extraterritorial jurisdiction’ element, which provides a
disjunctive list of circumstances under which the statute has extraterritorial reach . . . thus, any extraterritorial
application of the statute is limited by this list.”) (The court refers to the extraterritorial list in § 2339B(d)(1), but does
not mention the general extraterritorial statement in § 2339B(d)(2).); United States v. Elshinawy, 228 F. Supp. 3d 520,
538, 538 n.10 (D. Md. 2016) (“In order to satisfy its burden of proof as to these counts [under § 2339B], the
government must prove . . . that one of the jurisdictional requirements in the statute is satisfied.”) (citing to § 2339B(d)
but seeming to refer only to § 2339B(d)(1)); United States v. Jama, 217 F. Supp. 3d 882, 887 (E.D. Va. 2016) (“The
Court has jurisdiction as to each count [under § 2339B] with respect to each Defendant if, among other grounds, she is
a national . . . .”) (referring to some of the enumerated grounds for jurisdiction under § 2339B(d)(1), without any
apparent reliance on the general statement of jurisdiction under § 2339B(d)(2)).
198 United States v. Al Kassar, 660 F.3d 108, 118 (2d Cir. 2011); see also United States v. Naseer, 38 F. Supp. 3d 269,
272–73 (E.D.N.Y. 2014); Ahmed, 94 F. Supp. 3d at 408–09; but see In re Sealed Case, 936 F.3d 582, 593–94 (D.C. Cir.
2019) (“We have repeatedly declined, however, to hold that the Due Process Clause demands such a nexus—or to even
resolve ‘whether the Due Process Clause constrains the extraterritorial application of federal criminal laws’ at all. . . .
‘The animating principle governing the due process limits of extraterritorial jurisdiction,’ to the extent such limits exist,
‘is the idea that no man shall be held criminally responsible for conduct which he could not reasonably understand to be
proscribed.’”) (first quoting United States v. Ballestas, 795 F.3d 138, 148 (D.C. Cir. 2015); and then quoting United
States v. Ali, 718 F.3d 929, 944 (D.C. Cir. 2013)).
199 Section 2333 also permits recovery a victim’s estate, survivors, heirs.
200 18 U.S.C. § 2331(1)(A) (“the term ‘international terrorism’ means activities that –(A) involve violent acts or acts
dangerous to human life that are a violation of the criminal laws of the United States or of any State, or that would be a
criminal violation if committed within the jurisdiction of the United States or of any State. . . .”).
201 18 U.S.C. § 2331(1)(B) (“the term ‘international terrorism’ means activities that – . . . (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 . . . .”).
202 18 U.S.C. § 2331(1)(C) (“the term ‘international terrorism’ means activities that – . . . (C) occur primarily outside
the territorial jurisdiction of the United States, or transcend national boundaries in terms of the means by which they are
accomplished, the persons they appear intended to intimidate or coerce, or the locale in which their perpetrators operate
or seek asylum.”).
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Injuries resulting “by reason of” of the defendant’s conduct are those proximately caused by the
defendant’s conduct.203 The precise meaning of proximate cause, however, has long been a matter
of some dispute, as noted earlier with respect to § 2339A. Again, the Supreme Court has said “the
notion of proximate cause reflects ‘ideas of what justice demands, or of what is administratively
possible and convenient.’”204 In the Second and District of Columbia Circuits the § 2333
proximate cause test involves asking “(1) whether the defendants’ acts were a ‘substantial factor’
in the sequence of events’ that led to the plaintiffs’ injuries; and (2) whether those injuries were
‘reasonably foreseeable or anticipated as a natural consequence of’ defendants’ conduct.”205
The courts have concluded that the violations of § 2339A or § 2339B may constitute “acts of
international terrorism” under § 2333.206 They do so by construing violations of § 2339A or §
2339B as acts of “international terrorism” as defined in § 2331(1).207 Liability extends to those
who aid and abet a terrorist organization in its commission of acts of international
terrorism.208This aiding and abetting liability requires that the defendant “conscious[ly],

203 Crosby v. Twitter, Inc., 921 F.3d 617, 623 6th Cir. 2019); Fields v. Twitter, Inc., 881 F.3d 739, 744 (9th Cir. 2018);
Kemper v. Deutsche Bank AG, 911 F.3d 383, 391 (7th Cir. 2018); see also Retana v. Twitter, Inc., 1 F.4th 378, 384
(5th Cir. 2021) (“. . . the correct test for secondary liability is proximate cause. . . .”).
204 Holmes v. Sec. Inv. Prot. Corp., 503 U.S. 258, 268 (1992) (quoting W. PAGE KEETON ET AL., PROSSER AND KEETON
ON THE LAW OF TORTS § 41, p. 264 (5th ed. 1984)).
205 Crosby v. Twitter, Inc., 921 F.3d 617, 624 (6th Cir. 2019) (citing Owens v. BNP Paribas, S.A., 897 F.3d 266, 273
(D.C. Cir. 2018) and Rothstein v. UBS AG, 708 F.3d 82, 91 (2d Cir. 2013)) (holding plaintiffs before it had failed to
establish proximate cause).
206 Boim v. Quranic Literacy Inst., 291 F.3d 1000, 1015 (7th Cir. 2002) (“If the plaintiffs could show that [the
defendants] violated either section 2339A or section 2339B, that conduct would certainly be sufficient to meet the
definition of ‘international terrorism’ under sections 2333 and 2331. . . . Congress has made clear, though, through the
criminal liability imposed in sections 2339A and 2339B, that even small donations made knowingly and intentionally
in support of terrorism may meet the standard for civil liability in section 2333.”); Linde v. Arab Bank, PLC, 97 F.
Supp. 3d 287, 322 (E.D.N.Y. 2015) (“I agree with those courts that have held that a violation of 18 U.S.C. § 2339B is
itself an act of international terrorism. . . . Violations of 18 U.S.C. § 2339B and § 2339C are recognized as international
terrorism under 18 U.S.C. § 2333(a)”), vacated on other grounds, 882 F.2d 314 (2d Cir. 2018) (holding the
congressional addition of aiding and abetting liability did not apply retroactively); see also Abecassis v. Wyatt, 785 F.
Supp. 2d 614, 649 (S.D. Tex. 2011).
207 Boim v. Holy Land Found., 549 F.3d 685, 690 (7th Cir. 2008) (en banc) (“The first panel opinion discussed
approvingly an alternative and more promising ground for bringing donors to terrorist organizations within the grasp of
section 2333. The ground involves a chain of explicit statutory incorporations by reference. The first link in the chain is
the statutory definition of ‘international terrorism’ as ‘activities that . . . involve violent acts or acts dangerous to human
life that are a violation of the criminal laws of the United States,’ that ‘appear to be intended . . . to intimidate or coerce
a civilian population’ or ‘affect the conduct of a government by . . . assassination,’ and that ‘transcend national
boundaries in terms of the means by which they are accomplished’ or ‘the persons they appear intended to intimidate or
coerce.’ Section 2331(1) . . . includes not only violent acts but also ‘acts dangerous to human life that are a violation of
the criminal laws of the United States.’ Giving money to Hamas, like giving a loaded gun to a child (which also is not a
violent act), is an ‘act dangerous to human life.’ And it violates . . . 18 U.S.C. § 2339A(a), which provides that
‘whoever provides material support or resources . . . , knowing or intending that they are to be used in preparation for,
or in carrying out, a violation of [e.g.,] [18 U.S.C. § 2332],’ shall be guilty of a federal crime. So we go to 18 U.S.C.
§ 2332 and discover that it criminalizes the killing [of] . . . any American citizen outside the United States. By this
chain of incorporations by reference (section 2333(a) to section 2331(1) to section 2339A to section 2332), we see that
a donation to a terrorist group that targets Americans outside the United States may violate section 2333.” (alterations
4, 5, 7, 8, 9 in original)); Goldberg v. UNS AG, 690 F. Supp. 2d 92, 113 (E.D.N.Y. 2010) (“[S]ections 2339A and
2339B make clear Congress’ intent that the intentional (or reckless) provision of material support to a terrorist
organization fulfills each prong of section 2331(1)’s definition of ‘international terrorism,’ and therefore suffice to
establish liability under section 2333(a).”).
208 18 U.S.C. § 2333(d)(2) (“In an action under subsection (a) for an injury arising from an act of international
terrorism committed, planned, or authorized by an organization that had been designated as a foreign terrorist
organization under section 219 of the Immigration and Nationality Act (8 U.S.C. 1189), as of the date on which such
(continued...)
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voluntar[ily], and culpabl[y] participat[e]” in the terrorist’s act of violence.209 For reasons
mentioned earlier for § 2339A, victims have not found substantial success under § 2333. 210
Reporting Requirements
Section 2339B(a)(2) requires financial institutions to report assets held for a foreign terrorist
organization to the Secretary of the Treasury. Failure to do so subjects the institution to a civil
penalty of the greater of $50,000 or twice the value of the assets involved.211
Protection of Classified Information
Section 2339B(f) establishes a procedure to protect classified information during civil
proceedings brought by the government, complete with authority for interlocutory appeals by the
government.212
Section 2339A has no parallel provision, but the Classified Information Procedures Act213 affords
comparable protection.214
Courts may also close a portion of a criminal trial under some circumstances despite a
defendant’s Sixth Amendment right to a public trial.215

act of international terrorism was committed, planned, or authorized, liability may be asserted as to any person who
aids and abets, by knowingly providing substantial assistance, or who conspires with the person who committed such
an act of international terrorism.”).
209 Twitter, Inc. v. Taamneh, 143 S. Ct. 1206, 1223 (2023).
210 E.g., Seigel v. HSBC North America Holdings, Inc., 933 F.3d 217, 219 (2d Cir. 2019) (“[B]ecause the plaintiffs did
not adequately allege . . . that the defendants [(financial institutions that provided banking services to a Saudi bank that
in turn provided services to the terrorist organization)] knowingly played a role in the November 9 [terrorist] attacks or
provided substantial assistance to the terrorist organization that perpetrated it, they failed to state a plausible claim for
relief under JASTA.”); Crosby, 921 F.3d at 619 (“[Victims’] Plaintiffs’ complaint includes no allegations that Twitter,
Facebook, or Google [who allegedly hosted terrorist propaganda that ‘virtual recruit[ed] Americans to commit terrorist
attacks’] had any direct connection to Mateen or his heinous act.”); Kemper, 911 F.3d at 386 (“[Despite Congress’s
effort to make state sponsors of terrorism accountable in U.S. courts, see 28 U.S.C. § 1605A, any resulting judgment
may be uncollectible . . . Rhonda Kemper attempted to get around these formidable obstacles by alleging that the bomb
that killed her son was a signature Iranian weapon that traveled from the Iranian Revolutionary Guard Corps (‘the
Guard’) to Hezbollah to Iraqi militias, who then placed it in the ground . . . where it killed Spc. Schaefer. Kemper
asserts that Deutsche Bank AG, a German entity with U.S. affiliates, is responsible for her son’s death under . . . 18
U.S.C. § 2333. She ties Deutsche Bank to the fatal bomb through the Bank’s alleged membership in an Iranian
conspiracy to commit acts of terror. It joined that conspiracy, she contends, when it instituted procedures to evade U.S.
sanctions and facilitate Iranian banking transactions. The district court found that Kemper failed to plead facts that
plausibly indicated that Deutsche Bank’s actions caused her son’s death. . . . We affirm.”); see also Shatsky v. Palestine
Liberation Organization [PLO], 955 F.3d 1016, 1038 (D.C. Cir. 2020) (dismissing district court judgment over the
Palestine Authority and the PLO for want of personal jurisdiction); Boim v. American Muslims for Palestine, 9 F.4th
545, 548 (7th Cir. 2021) (citing some of the decades-long litigation of the Boim family’s efforts to recover for the
terrorist murder of their son in 1996); CRS Report R46274, The Palestinians and Amendments to the Anti-Terrorism
Act: U.S. Aid and Personal Jurisdiction
, by Jim Zanotti and Jennifer K. Elsea).
211 18 U.S.C. § 2339B(b).
212 The section is reminiscent of the Classified Information Procedures Act (18 U.S.C. App. 3) available to the
government in criminal cases.
213 18 U.S.C. App.3.
214 See, e.g., United States v. Al-Farekh, 956 F.3d 99 (2d Cir. 2020).
215 See, e.g., United States v. Hendricks, 950 F.3d 348, 355 (6th Cir. 2020) (no abuse of discretion for closing trial to
protect the identity of an undercover agent after alternatives proved ineffective) (“The right to a public trial, however,
‘may give way in certain cases to other rights or interests, such as a defendant’s right to a fair trial or the government’s
interest in inhibiting disclosure of sensitive information.’ These instances are ‘rare’ and ‘the balance of interests must
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be struck with special care.’ In turn, to justify partially closing a trial, (1) the moving party must show a ‘substantial
reason’ that is ‘likely to be prejudiced’ absent the closure, (2) the closure must be ‘narrowly tailored,’ (3) ‘the trial
court must consider reasonable alternatives,’ and (4) ‘the trial court must make findings adequate to support the
closure.’” (first quoting Waller v. Georgia, 467 U.S. 39, 45; and then quoting United States v. Simmons, 797 F.3d 409,
414 (6th Cir. 2015)); United States v. Alimehmeti, 284 F. Supp. 3d 477, 485–90 (S.D.N.Y. 2018).
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Author Information

Charles Doyle

Senior Specialist in American Public Law



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