Stripping foreign fighters of their citizenship: International human rights and humanitarian law considerations

Abstract

This article will briefly present a number of international human rights law considerations related to the topic of citizenship stripping of foreign fighters, that is: “individuals, driven mainly by ideology, religion and/or kinship, who leave their country of origin or their country of habitual residence to join a party engaged in an armed conflict”, most notably the conflict in Syria and Iraq. After that, the article will focus on considerations in the context of international humanitarian law, which have been less frequently the subject of academic debate. This contribution concludes that citizenship stripping is not only highly problematic under international human rights law, but also from the perspective of international humanitarian law. The measure – which is likely to constitute cruel, inhuman or degrading treatment or punishment – violates Article 3 Common to the four Geneva Conventions, but it also undermines accountability for international humanitarian law violations already committed and can engender new violations through the non-removal of the suspect from the conflict zone. One of the few positive sides of the connection between the measure and international humanitarian law is that even if nationality is deprived, this will not have an effect on the international humanitarian law obligation to treat that deprived person humanely. In that sense, international humanitarian law provides a welcome – albeit temporary – safety net of decent treatment for people who have become victims of countries’ refusal to take responsibility for their own citizens.

Full text

Stripping foreign
fighters of their
citizenship:
International human
rights and
humanitarian law
considerations
Christophe Paulussen
Dr Christophe Paulussen LL.M. M.Phil. is a senior researcher
at the T.M.C. Asser Instituut and coordinator of its research
strand “Human Dignity and Human Security in International
and European Law”, coordinator of the inter-faculty research
platform “International Humanitarian and Criminal Law
Platform”and research fellow at the International Centre for
Counter-Terrorism –The Hague. Christophe is also editor-in-
chief of the journal Security and Human Rights, member of the
Executive Board of the Royal Netherlands Society of
International Law, member of the Editorial Board of the Journal
of Human Trafficking, Enslavement and Conflict-Related Sexual
Violence and member of the Board of Advisors to the Editorial
Board of the Yearbook of International Humanitarian Law.
Email: C.Paulussen@asser.nl.
Abstract
This article will briefly present a number of international human rights law
considerations related to the topic of citizenship stripping of foreign fighters, that is:
“individuals, driven mainly by ideology, religion and/or kinship, who leave their
International Review of the Red Cross, Page 1 of 14.
doi:10.1017/S1816383121000278
©The Author(s), 2021. Published by Cambridge University Press on behalf of the ICRC. This is an
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country of origin or their country of habitual residence to join a party engaged in an
armed conflict”, most notably the conflict in Syria and Iraq. After that, the article will
focus on considerations in the context of international humanitarian law, which have
been less frequently the subject of academic debate. This contribution concludes that
citizenship stripping is not only highly problematic under international human rights
law, but also from the perspective of international humanitarian law. The measure –
which is likely to constitute cruel, inhuman or degrading treatment or punishment –
violates Article 3 Common to the four Geneva Conventions, but it also undermines
accountability for international humanitarian law violations already committed
and can engender new violations through the non-removal of the suspect from the
conflict zone. One of the few positive sides of the connection between the measure
and international humanitarian law is that even if nationality is deprived, this will
not have an effect on the international humanitarian law obligation to treat that
deprived person humanely. In that sense, international humanitarian law provides
a welcome –albeit temporary –safety net of decent treatment for people who have
become victims of countries’refusal to take responsibility for their own citizens.
Keywords: citizenship stripping, deprivation of nationality, foreign fighters, international humanitarian
law, international human rights law.
Introduction
Various armed conflicts around the world have attracted foreign fighters, who have
been defined as “individuals, driven mainly by ideology, religion and/or kinship,
who leave their country of origin or their country of habitual residence to join a
party engaged in an armed conflict”.
1
Examples are the British national George
Orwell, who participated in the Spanish civil war in the 1930s on the side of the
republicans, the Saudi national Osama bin Laden, who arrived in Afghanistan in
1 A. de Guttry, F. Capone and C. Paulussen, “Introduction”, in A. de Guttry, F. Capone and C. Paulussen
(eds), Foreign Fighters under International Law and Beyond, Asser Press/Springer: The Hague 2016, p. 2.
This definition (and hence also this article) excludes mercenaries, as the latter are motivated to take part in
the hostilities essentially by the desire for private gain. See also S. Krähenmann, Foreign Fighters under
International Law, Academy Briefing No. 7, Geneva Academy of International Humanitarian Law and
Human Rights, Geneva, October 2014, p. 16. However, for a different opinion, see UN General
Assembly, Use of Mercenaries as a Means of Violating Human Rights and Impeding the Exercise of the
Right of Peoples to Self-determination: Note by the Secretariat, A/73/303, United Nations, New York, 6
August 2018, para. 9: “In the absence of either an internationally agreed legal definition of foreign
fighters or a specific regime governing them, the Working Group has defined foreign fighters as
individuals who leave their country of origin or habitual residence and become involved in violence as
part of an insurgency or non-State armed group in an armed conflict. They are motivated by a range
of factors, notably ideology, although the Working Group has found financial motivations to be a key
factor as well. In this regard, the Working Group deems foreign fighters as a mercenary-related activity
[original footnote omitted].”For more information on the status of foreign fighters under international
humanitarian law more generally, see E. Sommario, “The Status of Foreign Fighters under
International Humanitarian Law”, in A. de Guttry, F. Capone and C. Paulussen (eds), above, pp. 141–160.
C. Paulussen
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1980 to challenge the Soviet occupation of that country, and, more recently, the
British national Mohammed Emwazi, better known as “Jihadi John”, who in 2012
travelled to Syria to join the Islamic State of Iraq and Syria (ISIS) and who would
become one of the terrorist organization’s most infamous executioners.
2
Notably
the conflict in Syria and Iraq has attracted an unprecedented number of foreign
fighters: on 28 November 2017, Vladimir Voronkov, Under-Secretary-General of
the United Nations (UN) and Head of its Office of Counter-Terrorism, briefed
the UN Security Council and “said that, at one stage more than 40,000 foreign
terrorist fighters from 110 countries might have travelled to join the conflict in
Syria and Iraq”.
3
Indeed, many of these foreign fighters joined terrorist groups,
such as al-Nusra or ISIS, which is why the attention quickly moved from foreign
fighters as such to foreign terrorist fighters (FTFs), defined by the UN Security
Council as “individuals who travel to a State other than their States of residence
or nationality for the purpose of the perpetration, planning, or preparation of, or
participation in, terrorist acts or the providing or receiving of terrorist training,
including in connection with armed conflict”.
4
In responding to the foreign fighter and especially the FTF phenomenon
and the groups that they have joined, states, and international and regional
organizations have implemented a broad set of measures, from a full-out military
campaign,
5
to criminal
6
and administrative measures.
7
It is interesting to note
that in the context of criminal law, the focus has recently shifted from the initial
limited counterterrorism perspective –with foreign fighters being mainly
prosecuted for membership of a terrorist organization –to broader charges,
showing the realization that foreign fighters can also commit crimes as
individuals participating in hostilities, such as war crimes.
8
But as the standards
of criminal law may be difficult to meet, especially in view of the difficulty of
securing evidence in (post-) conflict situations, states have increasingly resorted
to administrative measures. One of these is citizenship stripping or deprivation of
2 See more generally N. Arielli, From Byron to bin Laden: A History of Foreign War Volunteers, Harvard
University Press, Cambridge, MA, 2018.
3 UN Security Council, 8116th Meeting (PM), Greater Cooperation Needed to Tackle Danger Posed by
Returning Foreign Fighters, Head of Counter-Terrorism Office Tells Security Council, SC/13097, 28
November 2017, available at: https://www.un.org/press/en/2017/sc13097.doc.htm (all internet references
were accessed in July 2021).
4 UN Security Council, “Preambular”,inResolution 2178 (2014), S/RES/2178 (2014), 24 September 2014,
available at: http://www.securitycouncilreport.org/atf/cf/%7B65BFCF9B-6D27-4E9C-8CD3-CF6E4FF96FF9%
7D/s_res_2178.pdf,p.2.
5 See Operation Inherent Resolve, available at: https://www.inherentresolve.mil/About-CJTF-OIR/.
6 See C. Paulussen and K. Pitcher, “Prosecuting (Potential) Foreign Fighters: Legislative and Practical
Challenges”,ICCT Research Paper, January 2018, available at: https://icct.nl/app/uploads/2018/01/ICCT-
Paulussen-Pitcher-Prosecuting-Potential-Foreign-Fighters-Legislative-Practical-Challenges-Jan2018.pdf.
7 See B. Boutin, “Administrative Measures against Foreign Fighters: In Search of Limits and Safeguards”,
ICCT Research Paper, December 2016, available at: https://icct.nl/app/uploads/2016/12/ICCT-Boutin-
Administrative-Measures-December2016-1.pdf.
8 For further information on cumulative prosecution of foreign fighters, see the article by Hanne Cuyckens,
“Foreign Fighters and the Tension Between Counterterrorism and International Humanitarian Law: A
Case for Cumulative Prosecution Where Possible”, in this issue of the International Review of the Red
Cross.
Stripping foreign fighters of their citizenship: International human rights and
humanitarian law considerations
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nationality, a measure more and more used by states in the counterterrorism and
national security context, including against alleged foreign (terrorist) fighters.
This article will briefly present a number of international human rights law
considerations related to the topic of citizenship stripping of foreign fighters before
focusing on considerations in the context of international humanitarian law. These
are obviously the most interesting for the readers of the International Review of the
Red Cross and, moreover, they have been less frequently the subject of academic
debate. In the final part of this article, a number of conclusions will be offered.
Before starting though, the relevance of this contribution in this special
issue on “Counterterrorism and sanctions”must first be clarified. Indeed, should
citizenship stripping or deprivation of nationality (the two terms will be used
interchangeably here) be seen as a sanction in the first place? This contribution
argues that it should. Although the word “sanction”is often linked to
punishment, an objective sometimes lacking in the context of citizenship
stripping,
9
its scope is in fact broader. According to Black’s Law Dictionary,a
sanction is defined as, among other things, “[a] penalty or coercive measure that
results from failure to comply with a law, rule, or order”.
10
Deprivation of
nationality in any case fits the second part of this definition. But even if we were
to view a sanction to be limited to a penalty, and even if some governments
present citizenship stripping as a non-punitive measure meant to protect national
security, the connection to crime and punishment is in fact made at other times.
Sandra Mantu has, for example, noted that “we are actually witnessing a new way
of conceptualising state power whereby depriving individuals of their citizenship
status is a form of penal sanction to be applied to citizens in response to
perceived crimes against public security by act or by association [original footnote
omitted]”.
11
Hence, in all cases, it can be argued that citizenship stripping
constitutes a (de facto) sanction, even if we were to follow a definition limited to
measures of a punitive nature, and thus fits this special issue.
9 For example, when the Dutch Government, in December 2014, proposed a new bill on the amendment of
the Netherlands Nationality Act, to allow the Government to withdraw Dutch citizenship, without a
criminal conviction, when the person in question had joined an organization which is taking part in a
national or international armed conflict and which has been placed by the Minister of Security and
Justice on a list of organizations that constitute a threat to national security, the Minister clarified that
the objective of this measure is the protection of national security, which should be distinguished from
the objective of using criminal law. See C. Paulussen, “Repressing the Foreign Fighters Phenomenon
and Terrorism in Western Europe: Towards an Effective Response Based on Human Rights”,ICCT
Research Paper, November 2016, available at: https://icct.nl/app/uploads/2016/11/ICCT-Paulussen-
Rule-of-Law-Nov2016-1.pdf, p. 16. See also, more generally, M. Tripkovic, “Transcending the
Boundaries of Punishment: On the Nature of Citizenship Deprivation”,British Journal of Criminology,
23 February 2021, available at: https://academic.oup.com/bjc/advance-article-abstract/doi/10.1093/bjc/
azaa085/6146956, abstract: “Departing from a dominant perspective that considers denationalization as
punishment, this article conducts an original study of citizenship policies in 37 European democracies
and contrasts them with key principles of punishment. The findings raise serious doubts regarding the
penal nature of denationalization: I propose instead that denationalization is better understood as a sui
generis sanction, which seeks to relieve the polity of those members who fail to satisfy fundamental
citizenship requirements.”
10 B. A. Garner, Black’s Law Dictionary, 8th ed., Thomson West, St. Paul, MN, 2004, p. 1368.
11 S. Mantu, “Citizenship in Times of Terror: Citizenship Deprivation in the UK”,Nijmegen Migration Law
Working Papers Series, 2015/02, available at: https://repository.ubn.ru.nl/handle/2066/143370,p.5.
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International human rights law
12
This brief part will look at the legality of deprivation of nationality under
international human rights law. The measure has an impact on a crucial right,
namely the right to nationality, as can be found in various international and
regional human rights treaties.
13
The famous philosopher Hannah Arendt
referred in her The Origins of Totalitarianism to “the right to have rights”,
14
which clarifies immediately how serious the impact of deprivation of nationality
can be. For this reason alone, it has been argued that the measure can never be in
compliance with modern international human rights law.
15
It is submitted that
this is indeed correct. According to Article 8, paragraph 1 of the 1961
Convention on the Reduction of Statelessness, “[a] Contracting State shall not
deprive a person of its nationality if such deprivation would render him
stateless.”However, this rule is not the only element to consider. The basic rule
of the recent publication Principles on Deprivation of Nationality as a National
Security Measure, which was developed after two and half years of research,
involving more than 60 international experts and synthesizing all relevant
international standards, reads that “States shall not deprive persons of nationality
for the purpose of safeguarding national security.”
16
The Principles then explain
that if this happens nonetheless, “the exercise of this exception should be
interpreted and applied narrowly, only in situations in which it has been
determined by a lawful conviction that meets international fair trial standards,
that the person has conducted themselves in a manner seriously prejudicial to the
vital interests of the state”.
17
Moreover, this exception is further limited by other
international law standards, including not only the just-mentioned avoidance of
12 This part is based on C. Paulussen, “Towards a Right to Sustainable Security of Person in Times of
Terrorism? Assessing Possibilities and Limitations Through a Critical Evaluation of Citizenship
Stripping and Non-Repatriation Policies”,Journal of Conflict and Security Law, Vol. 26, Issue 1 (Spring
2021), available at: https://doi.org/10.1093/jcsl/kraa022, Section 2.B.
13 See Universal Declaration of Human Rights, Art. 15, para. 1; International Convention on the Elimination
of All Forms of Racial Discrimination, Art. 5, para. d(iii); Convention on the Elimination of All Forms of
Discrimination against Women, Art. 9; Convention on the Rights of the Child, Arts 7 and 8; American
Convention on Human Rights, Art. 20; European Convention on Nationality, Art. 4 (a); Arab Charter
on Human Rights, Art. 24; Covenant on the Rights of the Child in Islam, Art. 7; ASEAN Human
Rights Declaration, Art. 18; CIS Convention on Human Rights and Fundamental Freedoms, Art. 24.
See Institute on Statelessness and Inclusion, Draft Commentary to the Principles on Deprivation of
Nationality as a National Security Measure, 2020, available at: https://files.institutesi.org/PRINCIPLES_
Draft_Commentary.pdf, pp. 27–28.
14 See H. Arendt, The Origins of Totalitarianism, Penguin Classics, Random House UK, London, 2017,
pp. 388 and 390. See also L. Faghfouri Azar, “Hannah Arendt: The Right to Have Rights”,Critical
Legal Thinking, 12 July 2019, available at: https://criticallegalthinking.com/2019/07/12/hannah-arendt-
right-to-have-rights/.
15 See Office of the United Nations High Commissioner for Human Rights, Amicus Brief, Presented by the
UN Special Rapporteur on Contemporary Forms of Racism, Racial Discrimination, Xenophobia and Related
Intolerance. Before: The Dutch Immigration and Naturalisation Service, 23 October 2018, available at:
https://www.ohchr.org/Documents/Issues/Racism/SR/Amicus/DutchImmigration_Amicus.pdf, para. 25.
16 Institute on Statelessness and Inclusion, Principles on Deprivation of Nationality as a National Security
Measure, February 2020, available at: https://www.institutesi.org/year-of-action-resources/principles-on-
deprivation-of-nationality,p.9.
17 Ibid.
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statelessness, but also the prohibition of discrimination, the prohibition of arbitrary
deprivation of nationality, the right to a fair trial, remedy and reparation, and other
obligations and standards set forth in international human rights law, international
humanitarian law and international refugee law.
18
Zooming in on the prohibition of
arbitrary deprivation of nationality,
19
the Principles clarify that
[t]he deprivation of nationality of citizens on national security grounds is
presumptively arbitrary. This presumption may only be overridden in
circumstances where such deprivation is, at a minimum: […] Carried out in
pursuance of a legitimate purpose; […] Provided for by law; […] Necessary;
[…] Proportionate; and […] In accordance with procedural safeguards.
20
Zooming in even further on the element of proportionality, the Principles
subsequently stipulate that this requires that
[t]he immediate and long-term impact of deprivation of nationality on the
rights of the individual, their family, and on society is proportionate to the
legitimate purpose being pursued; […] The deprivation of nationality is
the least intrusive means of achieving the stated legitimate purpose; and […]
The deprivation of nationality is an effective means of achieving the stated
legitimate purpose.
21
Similar requirements have been brought forward in a more general way (in his
model provision on consistency of counterterrorism practices with human rights
and refugee law, and humanitarian law) by the first UN Special Rapporteur on
the promotion and protection of human rights and fundamental freedoms while
countering terrorism, Martin Scheinin. In his report Ten Areas of Best Practices in
Countering Terrorism, Scheinin writes that even if permissible under national law,
the exercise of certain functions and powers “may never violate peremptory or
non-derogable norms of international law, nor impair the essence of any human
right”
22
–such as the principles of non-discrimination and equality–
23
and
[w]here the exercise of functions and powers involves a restriction upon a
human right that is capable of limitation, any such restriction should be to
18 Ibid.
19 See also Institute on Statelessness and Inclusion, above note 13, pp. 43–65; and OSCE Office for
Democratic Institutions and Human Rights (ODIHR), Guidelines for Addressing the Threats and
Challenges of “Foreign Terrorist Fighters”within a Human Rights Framework, 2018, available at:
https://www.osce.org/files/f/documents/4/7/393503_2.pdf, pp. 49–51.
20 Institute on Statelessness and Inclusion, above note 16, p. 10.
21 Ibid., pp. 11–12.
22 Human Rights Council, Report of the Special Rapporteur on the Promotion and Protection of Human
Rights and Fundamental Freedoms While Countering Terrorism, Martin Scheinin: Ten Areas of Best
Practices in Countering Terrorism, A/HRC/16/51, para. 16.
23 See OSCE Office for Democratic Institutions and Human Rights (ODIHR), above note 19, p. 32; UN
Counter-Terrorism Implementation Task Force (CTITF), Working Group on Protecting Human
Rights while Countering Terrorism, Basic Human Rights Reference Guide: Security Infrastructure,
Updated 2nd ed., March 2014, para. 5; and UN General Assembly, Report of the Special Rapporteur on
Contemporary Forms of Racism, Racial Discrimination, Xenophobia and Related Intolerance, A/72/287,
4 August 2017, para. 47.
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the least intrusive means possible and shall: (a) Be necessary in a democratic
society to pursue a defined legitimate aim, as permitted by international law;
and (b) Be proportionate to the benefit obtained in achieving the legitimate
aim in question.
24
As argued before,
25
deprivation of nationality can never be seen as the least intrusive
means available and be necessary and proportionate. After all, mono-citizens who
may have been in the same situation, who may have committed similar crimes
and who may pose a similar security risk will not be deprived of their nationality
(to avoid statelessness) but will face other, less far-going measures, such as a
temporary area ban. If mono-citizens can be responded to in a less intrusive way,
then why can these responses not also be applied to dual citizens? This entails
that it is extremely difficult to justify deprivation of nationality as the least
intrusive and thus necessary and proportionate means towards a certain aim,
hence making the measure arbitrary, and thus prohibited under international law.
Moreover, as explained above, the measure may never violate peremptory or non-
derogable norms of international law, nor impair the essence of any human right,
such as the principles of non-discrimination and equality.
26
In this respect,
serious problems under international law arise as well, for the measure can and
will only be applied to dual citizens. This clearly creates two different classes of
citizens. Indeed, in an amicus curiae brief submitted to the Dutch Immigration
and Naturalisation Service, the UN Special Rapporteur on contemporary forms of
racism, racial discrimination, xenophobia and related intolerance E. Tendayi
Achiume likewise concluded:
The Netherlands’policy to subject Dutch citizens to differential treatment on the
basis of their mono or dual citizenship is inconsistent with its international
human rights law [obligations]. The Netherlands’policy to use individuals’
status as Dutch mono or dual nationals to determine eligibility for citizenship
revocation results in discriminatory tiers of citizenship: full citizenship for
Dutch mono nationals and less-secure citizenship for Dutch dual nationals.
Because this result contradicts its international human rights law obligations
to guarantee equality before the law and equal protection of the law to all of
its citizens, the Netherlands must not rely on any mono-/dual-nationality
distinction in determining permissibility of citizenship revocation.
27
This brief part has demonstrated that deprivation of nationality is highly
problematic under international human rights law. But the measure is also
24 Human Rights Council, above note 22, para. 16.
25 C. Paulussen, above note 12, p. 226.
26 See also Institute on Statelessness and Inclusion, above note 16, p. 10: “[a] State must not deprive any
person or group of persons of their nationality as a result of direct or indirect discrimination in law or
practice, on any ground prohibited under international law, including race, colour, sex, language,
religion, political or other opinion, national or social origin, ethnicity, property, birth or inheritance,
disability, sexual orientation or gender identity, or other real or perceived status, characteristic or
affiliation.”
27 Office of the United Nations High Commissioner for Human Rights, above note 15, para. 36.
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problematic for other reasons. For example, it removes important jurisdictional
links to try possible offenders, it undermines international cooperation to fight
impunity; it can, through its discriminatory character, lead to even more
alienation and resentment and thus possible radicalization in minority groups,
who are disproportionally targeted by the measure, and finally it can increase
long-term security risks.
28
Nonetheless, “only”the problematic international
human rights law dimension should already be enough to conclude that the
measure is not to be resorted to.
International humanitarian law
Although international human rights law is clearly relevant, and has thus also been
discussed in the literature when assessing the legality of the measure,
29
the centre of
attention of this article will be on discussing the measure from a quite novel
perspective, that is, in the context of the International Review of the Red Cross’s
main field of focus: international humanitarian law. Indeed, what are the links
between deprivation of nationality and international humanitarian law?
To start with, and this will not come as a surprise, the measure of
deprivation of nationality or citizenship stripping itself is not to be found in
conventional
30
and customary
31
international humanitarian law. This is different
for the concept of nationality as such, although it is usually seen as an irrelevant
criterion to international humanitarian law,
32
for instance when it comes to
providing protection and care. An example can be found in Article 12 of the First
and Second Geneva Conventions, which stipulates that the protected persons of
these Conventions “shall be treated humanely and cared for by the Party [Geneva
Convention I]/Parties [Geneva Convention II] to the conflict in whose power
they may be, without any adverse distinction founded on sex, race, nationality,
religion, political opinions, or any other similar criteria”.
33
At other times though,
nationality is taken into account, for instance in the context of prescriptions
28 For more on this, see again C. Paulussen, above note 12, pp. 219–249.
29 See especially the work of Laura van Waas in this field, including L. van Waas, “Foreign Fighters and the
Deprivation of Nationality: National Practices and International Law Implications”, in A. de Guttry,
F. Capone and C. Paulussen (eds), above note 1, pp. 469–487.
30 For this purpose, the texts of the four Geneva Conventions and the three Additional Protocols were
searched.
31 For this purpose, the Customary International Humanitarian Law Study of the ICRC, Vol. 1: Rules was
searched.
32 See e.g. Geneva Convention (I) for the Amelioration of the Condition of the Wounded and Sick in Armed
Forces in the Field of 12 August 1949, 75 UNTS 31 (entered into force 21 October 1950) (GC I), Arts 18
and 49; Geneva Convention (II) for the Amelioration of the Condition of Wounded, Sick and Shipwrecked
Members of Armed Forces at Sea of 12 August 1949 (entered into force 21 October 1950) (GC II), Arts 14,
30 and 50. Nationality is also irrelevant “for determining whether a particular person can be qualified as a
combatant and hence is entitled to POW status (with the possible exception of nationals of the detaining
power) [original footnotes omitted]”. S. Krähenmann, above note 1, pp. 17–18.
33 See also Geneva Convention (III) relative tothe Treatment of Prisoners of War of 12 August 1949 (entered
into force 21 October 1950) (GC III), Art. 16; and Geneva Convention (IV) relative to the Protection of
Civilian Persons in Time of War of 12 August 1949 (entered into force 21 October 1950) (GC IV), Art. 13.
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regarding the dead,
34
internment
35
or “in determining whether civilians in the
hands of the enemy are protected under Geneva Convention IV”.
36
As regards
the last example, Article 4 of Geneva Convention IV stipulates that
[p]ersons protected by the Convention are those who, at a given moment and in
any manner whatsoever, find themselves, in case of a conflict or occupation, in
the hands of a Party to the conflict or Occupying Power of which they are not
nationals. Nationals of a State which is not bound by the Convention are not
protected by it. Nationals of a neutral State who find themselves in the
territory of a belligerent State, and nationals of a co-belligerent State, shall
not be regarded as protected persons while the State of which they are
nationals has normal diplomatic representation in the State in whose hands
they are.
Although Geneva Convention IV will usually not be relevant to the phenomenon of
foreign fighters, as most of them are involved in non-international armed
conflicts,
37
the provision shows that, in theory, deprivation of nationality could
have an effect on an individual’s protection. Imagine a foreign fighter who has
two nationalities, each of a neutral State, and that the country of second
nationality, in contrast to the country of first nationality, has no “normal
diplomatic representation in the State in whose hand [the foreign fighter is]”.It
seems that this would mean that if the country of first nationality revokes
nationality, the foreign fighter, now only in the possession of the nationality of
the second country, would be regarded as a protected person under Geneva
Convention IV, whereas if he or she still had ties to the country which has
normal diplomatic representation in the State in whose hands he or she is, he or
she would not. Sandra Krähenmann has explained that the exclusions of Article 4
of Geneva Convention IV “are based on the premise that nationals of neutral or
co-belligerent states will be protected by their state of origin through normal
diplomatic channels, including exercise of diplomatic protection […], and
therefore do not need the additional protection provided by Geneva Convention
IV.”
38
But in the case of citizenship stripping, this basic premise is undermined,
as the country of origin does not protect its own citizen but, to the contrary,
passes the buck to other actors.
39
The above-mentioned consequence would not only follow for those foreign
fighters not directly participating in hostilities (the term foreign fighter is a little
34 See GC I, Art. 17.
35 See GC III, Art. 22; and GC IV, Art. 82.
36 S. Krähenmann, above note 1, p. 18.
37 Ibid., p. 15.
38 Ibid., p. 18.
39 Sandra Krähenmann has noted that the Appeals Chamber of the International Criminal Tribunal for the
former Yugoslavia in the Tadićcase replaced the nationality standard by the concept of allegiance and that
“[a]rguably, a similar reasoning could apply to foreign fighters whose allegiance is not defined by
nationality, but religion or ideology. Such an approach might be especially relevant when states of
origin show reluctance to exercise diplomatic protection on their behalf [original footnotes omitted]”.
(Ibid., p. 19.)
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misleading but “join[ing] a party engaged in an armed conflict”does not necessarily
mean being involved in direct participation in hostilities, which entails carrying out
“specific acts […] as part of the conduct of hostilities between parties to an armed
conflict”).
40
Also “[c]ivilians who directly participate in hostilities […] remain
protected civilians when they fall into the hands of the enemy, provided they
fulfil the nationality criteria set out in Article 4”.
41
It is also interesting to see where nationality is not mentioned in the
different texts. For instance, in paragraph 1 of Article 3 common to the four
Geneva Conventions –and this provision is of course of particular interest to the
phenomenon of foreign fighters, as most of these fighters are active in non-
international armed conflicts –nationality is not listed as a prohibited ground for
adverse distinction among protected persons:
Persons taking no active part in the hostilities, including members of armed
forces who have laid down their arms and those placed hors de combat by
sickness, wounds, detention, or any other cause, shall in all circumstances be
treated humanely, without any adverse distinction founded on race, colour,
religion or faith, sex, birth or wealth, or any other similar criteria.
The question is of course whether nationality would fall under the concept of “other
similar criteria”? According to the 2016 Commentary to common Article 3, that is
indeed the case. Although
the Working Party preparing the draft of the final text of common Article 3 at
the 1949 Diplomatic Conference […] decided not to include nationality as a
criterion, given that it might be perfectly legal for a government to treat
insurgents who are its own nationals differently in an adverse sense from
foreigners taking part in a civil war [for instance “foreign fighters”],
42
this different treatment “has no bearing on common Article 3’s imperative of humane
treatment without any adverse distinction.”
43
Hence, although “[i]n the domestic
judicial assessment of a non-international armed conflict, nationality may be regarded
as an aggravating or extenuating circumstance, […] it cannot be regarded as affecting
in any way the humanitarian law obligation of humane treatment [emphasis added]”.
44
To conclude this part, the measure of deprivation of nationality or
citizenship stripping cannot be found in international humanitarian law and the
concept of nationality is irrelevant when it comes to fundamental guarantees of
humane treatment under international humanitarian law. Indeed, in theory states
40 “Interpretive Guidance on the Notion of Direct Participation in Hostilities under International
Humanitarian Law, Adopted by the Assembly of the International Committee of the Red Cross on 26
February 2009”,International Review of the Red Cross, Vol. 90, No. 872 (December 2008), available at:
https://www.icrc.org/en/doc/assets/files/other/irrc-872-reports-documents.pdf, p. 995.
41 S. Krähenmann, above note 1, p. 18.
42 ICRC, Commentary of 2016. Article 3: Conflicts not of an International Character, available at: https://ihl-
databases.icrc.org/applic/ihl/ihl.nsf/Comment.xsp?action=openDocument&documentId=59F6CDFA490736
C1C1257F7D004BA0EC, para. 571.
43 Ibid., para 572.
44 Ibid.
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could deprive someone of nationality under domestic law,
45
but that deprivation
cannot affect that person’s humane treatment under international humanitarian law.
A clearer link between the measure and international humanitarian law can be
identified in the following context: according to Rule 158 of the Customary
International Humanitarian Law Study of the ICRC,Vol.1:Rules,“States must
investigate war crimes allegedly committed by their nationals or armed forces, or on
their territory, and, if appropriate, prosecute the suspects. They must also investigate
other war crimes over which they have jurisdiction and, if appropriate, prosecute
the suspects.”
46
It is undisputed that foreign fighters, often as members of groups
such as ISIS, have committed the most horrible war crimes.
47
It can be argued that
if states, rather than investigating the war crimes allegedly committed by their
nationals, instead rescind responsibility by depriving them of their nationality and
make their former nationals the problem of other actors, they violate this customary
international humanitarian law obligation. Indeed, as also briefly mentioned at the
end of the previous part, deprivation of nationality removes an important
jurisdictional link to try possible offenders, the active nationality principle, and thus
undermines the fight against impunity.
48
By violating this customary international
humanitarian law obligation, states also violate the more general obligation of UN
Security Council Resolution 2178, the most authoritative resolution on the
phenomenon of FTFs, that “Member States must ensure that any measures taken to
counter terrorism [such as deprivation of nationality] comply with all their
obligations under international law, in particular international human rights law,
international refugee law, and international humanitarian law”.
49
45 Although the conclusion of the previous part should be repeated here again, namely that under
international human rights law, the measure is highly problematic.
46 J.-M. Henckaerts and L. Doswald-Beck, Customary International Humanitarian Law, Vol. 1: Rules,
Cambridge University Press: Cambridge, 2005 (reprinted with corrections 2009), p. 607.
47 See e.g. Eurojust, Network for Investigation and Prosecution of Genocide, Crimes against Humanity and
War Crimes, Cumulative Prosecution of Foreign Terrorist Fighters for Core International Crimes and
Terrorism-related Offences, The Hague, May 2020, available at: https://www.eurojust.europa.eu/sites/
default/files/Partners/Genocide/2020-05_Report-on-cumulative-prosecution-of-FTFs_EN.PDF,pp.12–13:
“The Reports of the Independent International Commission of Inquiry on the Syrian Arab Republic (UN
CoI Syria) stated that ISIS had endangered and directed acts of violence against the civilian population in
areas controlled by them, and persons not taking part in hostilities. Accordingly, they committed the war
crimes of murder, execution without due process, mutilation, enforced disappearance, torture, cruel
treatment, hostage-taking, rape and sexual violence, forced pregnancy, the use and recruitment of
children in hostilities and attacking protected objects, forcibly displacing civilians, outrages upon personal
dignity as well as other serious violations of IHL [international humanitarian law]. ISIS violated its
obligations towards civilians and persons hors de combat which amounted to war crimes by beheading,
shooting and stoning men, women, children and captured soldiers. They mutilated their bodies and
carried out amputations and lashings in public spaces. Prisoners of ISIS had to survive beatings,
whipping, electrocution, and suspension from walls or ceilings. Moreover, ISIS was engaged in
abductions, and women and girls suffered from sexual slavery, gang raping, executions for unapproved
contact with the opposite sex and stoning for adultery. According to the UN CoI Syria, the commanders
of ISIS had wilfully perpetrated these war crimes with the indisputable intent of attacking persons while
they were aware of their status as civilians or persons no longer participating in hostilities. Yazidis were
especially targeted by horrific abuse by ISIS due to their community’s religious identity [original
footnotes omitted].”
48 H. Cuyckens, above note 8, “Domestic prosecution in the country of origin”section.
49 UN Security Council, above note 4, p. 1.
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It is admitted that stripping of citizenship and thus the removal of the active
nationality principle does not mean that investigation and prosecution of war crimes
committed by one’s former nationals will never be possible. After all, Rule 157 of the
same Customary International Humanitarian Law Study of the ICRC,Vol.1:Rules
clarifies that “States have the right to vest universal jurisdiction in their national
courts over war crimes”.
50
However, in practice, one can see that investigation and
prosecution based on “pure”universal jurisdiction
51
–especially after Belgium
experienced the political consequences of such a broad law –
52
are scarce, and that
the exercise of universal jurisdiction has now often been made dependent on
certain conditions. In the Netherlands, for example, the International Crimes Act
of 2003 stipulates that universal jurisdiction for international crimes such as war
crimes committed abroad is conditional upon the suspect’spresenceinthe
Netherlands.
53
Hence, if a Dutch foreign fighter’s citizenship is stripped,
prosecution for war crimes may still be possible under universal jurisdiction, but
only if that person is present in the Netherlands, which often will not be the case.
It has therefore also been argued that the Netherlands should stop applying the
measure of deprivation of nationality, for it undermines accountability efforts
among other things, not only in the context of terrorist crimes, but also in the
context of international crimes such as war crimes.
54
Going further, the point
could be made that if a state does not bring its foreign fighters to justice (either in
its own courts or elsewhere), it will not only undermine the fight against impunity
for crimes already committed, but also it may lead to a prolongation of the
conflict,
55
which, in turn, will lead to new international humanitarian law violations.
56
50 J.-M. Henckaerts and L. Doswald-Beck, above note 46, p. 604.
51 “Pure universal jurisdiction takes place when a state asserts jurisdiction (either through an investigation or
by seeking extradition) of a suspect who is not present in the state’s territory.”See International Center for
Transitional Justice, Advancing Global Accountability: The Role of Universal Jurisdiction in Prosecuting
International Crimes, December 2020, available at: https://www.ictj.org/sites/default/files/ICTJ_Report_
Universal_Jurisdiction.pdf, p. 13.
52 See e.g. S. R. Ratner, “Belgium’s War Crimes Statute: A Postmortem”,American Journal of International
Law, Vol. 97, No. 4, 2003, pp. 888–897.
53 Netherlands International Crimes Act, 2003, Section 2, para. 1 (a).
54 See C. Paulussen, Reactie op het wetsvoorstel permanentmaking bevoegdheid tot intrekking
Nederlanderschap in het belang van de nationale veiligheid (Keten-ID: 10430), 25 January 2021,
available at: https://www.internetconsultatie.nl/intrekkingnederlanderschap/reactie/152199/bestand,
pp. 4–6.
55 See also UN Security Council, “Preambular: ‘Concerned that foreign terrorist fighters increase the
intensity, duration and intractability of conflicts’”,inResolution 2178 (2014), S/RES/2178 (2014), 24
September 2014, available at: http://www.securitycouncilreport.org/atf/cf/%7B65BFCF9B-6D27-4E9C-
8CD3-CF6E4FF96FF9%7D/s_res_2178.pdf,p.2.
56 See also Council of Europe Parliamentary Assembly, Withdrawing Nationality as a Measure to Combat
Terrorism: a Human-rights Compatible Approach?, Resolution 2263 (2019), available at: http://assembly.
coe.int/nw/xml/XRef/Xref-XML2HTML-en.asp?fileid=25430&lang=en, para. 8: “The Assembly also
notes that the practice of depriving of their nationality persons involved in terrorist activities
(including “foreign fighters”) or suspected of such involvement may lead to the “exporting of risks”,as
those persons may move to or remain in terrorist conflict zones outside Europe. Such a practice goes
against the principle of international co-operation in combating terrorism, reaffirmed, inter alia,inUN
Security Council Resolution 2178 (2014), which aims at preventing foreign fighters from leaving their
State of residence or nationality, and may expose local populations to violations of international
human rights and humanitarian law.”
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Finally, the already mentioned Principles on Deprivation of Nationality as a
National Security Measure clarify in Principle 9.3.2 that “[d]eprivation of nationality
is likely to constitute cruel, inhuman or degrading treatment or punishment,
particularly where it results in statelessness”.
57
As regards the deprivation itself:
the Draft Commentary to the Principles, referring to the cases Maritza Urrutia
v. Guatemala (Inter-American Court of Human Rights)
58
and Trop v. Dulles
(United States Supreme Court),
59
explains that the measure “may cause severe
mental suffering, as the identity of the person concerned has been taken away
and that person is left in a state of uncertainty.”
60
In addition to the deprivation
itself, measures following citizenship stripping, such as statelessness,
61
could even
amount to torture.
62
As such, citizenship stripping is a violation not only of
international human rights law, but also of international humanitarian law, such
as common Article 3. This provision was applicable to several Western countries
depriving their former citizens of nationality as these countries, such as the
Netherlands and the United Kingdom, were “involved in the non-international
armed conflicts against the Islamic State group in Iraq and Syria by undertaking
airstrikes as part of the international coalition led by the United States.”
63
Conclusion
This brief contribution has demonstrated that depriving foreign fighters of their
nationality is problematic from a variety of perspectives, not only from an
international human rights law point of view (in which context the measure has
already been addressed before), but also from the standpoint of the International
Review of the Red Cross’s main field of focus: international humanitarian law. As
just mentioned, the measure in itself –which is likely to constitute cruel, inhuman
or degrading treatment or punishment –violates common Article 3. However,
also from a more indirect standpoint the measure should not be resorted to: it
clearly undermines accountability for international humanitarian law violations
already committed and can engender new violations through the non-removal of
the suspect from the conflict zone. One of the few positive sides of the
connection between the measure and international humanitarian law is that even
57 Institute on Statelessness and Inclusion, above note 16, p. 14.
58 Institute on Statelessness and Inclusion, above note 13, p. 77: “the elements of the concept of torture […]
include methods to obliterate the personality of the victim in order to attain certain objectives, such as
intimidation or punishment.”
59 Ibid.: “[T]he punishment [of denaturalization is cruel and unusual as it] strips the citizen of his status in
the national and international political community. […] In short, the expatriate has lost the right to have
rights.”Here, the Supreme Court is clearly echoing the earlier-mentioned words of Hannah Arendt.
60 Ibid.
61 It is recalled that deprivation of nationality may not lead to statelessness; see the earlier reference to the
1961 Convention on the Reduction of Statelessness. However, in practice, this still happens, either de jure
or de facto.
62 Institute on Statelessness and Inclusion, above note 13, p. 77.
63 Geneva Academy, RULAC, Netherlands, available at: https://www.rulac.org/browse/countries/the-
netherlands.
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if nationality is deprived, this will not have an effect on, for example, the
international humanitarian law obligation to treat that deprived person
humanely. In that sense, international humanitarian law provides a welcome –
albeit temporary –safety net of decent treatment for people who have become
victims of countries’refusal to take responsibility for their own citizens.
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