Hostname: page-component-78c5997874-xbtfd Total loading time: 0 Render date: 2024-11-13T03:55:46.319Z Has data issue: false hasContentIssue false
  • English
  • Français

RECONCEPTUALISING THE LEGAL RESPONSE TO FOREIGN FIGHTERS

Published online by Cambridge University Press:  04 December 2019

John Ip Open the ORCID record for John Ip [Opens in a new window]
John Ip*
Affiliation:
Senior Lecturer in Law, University of Auckland, j.ip@auckland.ac.nz.
Get access Rights & Permissions [Opens in a new window]

Abstract

The Syrian civil war has highlighted the phenomenon of foreign fighting, in which individuals leave their home State to join an armed conflict overseas. The predominant paradigm for regulating foreign fighting, centred on United Nations Security Council Resolution 2178, is based on counterterrorism, which in essence treats foreign fighting as a form of terrorism. This paradigm is largely reflective of the domestic legislation of the United Kingdom, United States, Canada and Australia. This article argues that this approach is problematic, and that an alternative paradigm based on the international law of neutrality and related domestic legislation provides a better means for regulating foreign fighting.

Keywords

public international lawforeign fighterforeign terrorist fighterforeign volunteerUnited Nations Security Council Resolution 2178terrorismneutrality law
Type
Articles
Information
International & Comparative Law Quarterly , Volume 69 , Issue 1 , January 2020 , pp. 103 - 134
Copyright
Copyright © The Author (2019). Published by Cambridge University Press for the British Institute of International and Comparative Law.

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

Footnotes

My thanks to An Hertogen, Arie Rosen, participants at seminars held at the University of Auckland and KU Leuven, as well as the journal's reviewers for helpful comments on this article. Any errors remain my own.

References

1 See Andrew, C, The Secret World (Allen Lane 2018) 193–5CrossRefGoogle Scholar.

2 Arielli, N, From Byron to Bin Laden (Harvard University Press 2018) 24–5CrossRefGoogle Scholar.

3 Heinsch, R, ‘Foreign Fighters and International Criminal Law’ in de Guttry, A, Capone, F and Paulussen, C (eds), Foreign Fighters under International Law and Beyond (TMC Asser Press 2016) 165Google Scholar; Ragni, C, ‘International Legal Implications Concerning ‘Foreign Terrorist Fighters’’ (2018) 101 Rivista di Diritto Internazionale 1052, 1062–3Google Scholar.

4 Krähenmann, S, ‘The Obligations under International Law of the Foreign Fighter's State of Nationality or Habitual Residence, State of Transit and State of Destination’ in de Guttry, A, Capone, F and Paulussen, C (eds), Foreign Fighters under International Law and Beyond (TMC Asser Press 2016) 241Google Scholar.

5 UNSC Res 2178 (24 September 2014) UN Doc S/RES/2178.

6 See Forcese, C and Sherriff, L, ‘Killing Citizens: Core Legal Dilemmas in the Targeted Killing of Canadian Foreign Terrorist Fighters’ (2017) 54 Canadian Yearbook of International Law 134, 139Google Scholar; Lloydd, M, ‘Foreign Fighters under International Law and Beyond’ (2017) 18 Melbourne Journal of International Law 95, 96Google Scholar.

7 Malet, D, ‘Foreign Fighter Mobilization and Persistence in a Global Context’ (2015) 27 Terrorism and Political Violence 454, 455–9CrossRefGoogle Scholar.

8 Hegghammer, T, ‘The Rise of Muslim Foreign Fighters: Islam and the Globalization of Jihad’ (2011) 35 International Security 53, 57–8Google Scholar.

9 Malet, D, Foreign Fighters: Transnational Identity in Civil Conflicts (Oxford University Press 2013) 9CrossRefGoogle Scholar.

10 ibid 9.

11 S Krähenmann, ‘Foreign Fighters under International Law’ (Geneva Academy of International Humanitarian Law and Human Rights, October 2014) <https://www.geneva-academy.ch/joomlatools-files/docman-files/Publications/Academy%20Briefings/Foreign%20Fighters_2015_WEB.pdf > 5.

12 Hegghammer (n 8) 58.

13 See C Walker, ‘Foreign Terrorist Fighters and UK Counter Terrorism Law’ in D Anderson, ‘The Terrorism Acts in 2015’ (December 2016) <https://terrorismlegislationreviewer.independent.gov.uk/wp-content/uploads/2016/12/TERRORISM-ACTS-REPORT-1-Dec-2016-1.pdf> 98; J Fritz and JK Young, ‘Transnational Volunteers: American Foreign Fighters Combating the Islamic State’ (2017) Terrorism and Political Violence <https://doi.org/10.1080/09546553.2017.1377075> 2–5.

14 Henckaerts, J and Doswald-Beck, L, Customary International Humanitarian Law Volume 1: Rules (Cambridge University Press 2005) 13CrossRefGoogle Scholar; Krähenmann (n 4) 240–1.

15 Krähenmann (n 4) 241; AP Schmid and J Tinnes, ‘Foreign (Terrorist) Fighters with IS: A European Perspective’ (ICCT Research Paper, December 2015) <https://icct.nl/wp-content/uploads/2015/12/ICCT-Schmid-Foreign-Terrorist-Fighters-with-IS-A-European-Perspective-December2015.pdf> 13.

16 For example, in ISIL's extensive media/propaganda operation: see Sexton, M, ‘What's in a Name?’ (2017) 162 The RUSI Journal 34, 36Google Scholar.

17 Arielli (n 2) 38.

18 Chesterman, S, ‘Dogs of War or Jackals of Terror? Foreign Fighters and Mercenaries in International Law’ (2016) 18 IntCLRev 389, 390Google Scholar; Percy, S, Mercenaries: The History of a Norm in International Relations (Oxford University Press 2007) 56CrossRefGoogle Scholar.

19 Fritz and Young (n 13) 5.

20 de Guttry, A, Capone, F and Paulussen, C, ‘Introduction’ in de Guttry, A, Capone, F and Paulussen, C (eds), Foreign Fighters under International Law and Beyond (TMC Asser Press 2016) 2CrossRefGoogle Scholar. See also Ragni (n 3) 1052.

21 See Arielli (n 2); Malet (n 9).

22 Sykes, P, ‘Denaturalisation and Conceptions of Citizenship in the ‘‘War on Terror’’’ (2016) 20 Citizenship Studies 749, 750CrossRefGoogle Scholar.

23 One third of ISIL's fighting force was at one time reportedly comprised of foreign fighters. The majority came from the Middle East and Maghreb region, while 20 per cent came from Europe: Schmid and Tinnes (n 15) 11–12. See also 1267 Committee, ‘Twenty-fourth Report of the Analytical Support and Sanctions Monitoring Team Submitted Pursuant to Resolution 2368 (2017) Concerning ISIL (Da'esh), Al-Qaida and Associated Individuals and Entities’ (15 July 2019) S/2019/570 para 48.

24 UNSC Res 2170 (15 August 2014) UN Doc S/RES/2170.

25 UNSC Res 2178 (24 September 2014) UN Doc S/RES/2178, preamble.

26 Krähenmann (n 4) 236–7.

27 Sexton (n 16) 39.

28 ibid 35.

29 Sexton suggests it is preferable to disaggregate and distinguish between different types of participation and tailor interventions and sanctions accordingly: ibid 40. See also Malet (n 7) 458–9.

30 UNSC Res 2178 (24 September 2014) UN Doc S/RES/2178, preamble.

31 See generally 1267 Committee (n 23) paras 1–8; R Barrett, ‘Beyond the Caliphate: Foreign Fighters and the Threat of Returnees’ (The Soufan Group, October 2017) <http://thesoufancenter.org/wp-content/uploads/2017/11/Beyond-the-Caliphate-Foreign-Fighters-and-the-Threat-of-Returnees-TSC-Report-October-2017-v3.pdf>.

32 United Nations Counter-Terrorism Committee Executive Directorate, ‘The Challenge of Returning and Relocating Foreign Terrorist Fighters: Research Perspectives’ (CTED Trends Report, March 2018) <https://www.un.org/sc/ctc/wp-content/uploads/2018/04/CTED-Trends-Report-March-2018.pdf> 6. Of course, only a subset of those foreign fighters who return will constitute threats: see D Byman, ‘The Jihadist Returnee Threat: Just How Dangerous?’ (2016) 131 Political Science Quarterly 69, 84–91.

33 Byman (n 32) 72–3.

34 1373 Committee, ‘Implementation of Security Council Resolution 2178 (2014) by States Affected by Foreign Terrorist Fighters’ (14 May 2015) S/2015/338 para 23.

35 F Ragazzi and J Walmsley, ‘The Return of Foreign Fighters to EU Soil’ (European Parliamentary Research Service, May 2018) <http://www.europarl.europa.eu/RegData/etudes/STUD/2018/621811/EPRS_STU(2018)621811_EN.pdf> 26. The Paris and Brussels attacks involved individuals who were specifically directed to return to Europe to launch such attacks: see Barrett (n 31) 21.

36 Hegghammer, T, ‘Should I Stay or Should I Go? Explaining Variation in Western Jihadists’ Choice between Domestic and Foreign Fighting’ (2013) 107 American Political Science Review 1, 10CrossRefGoogle Scholar.

37 Hegghammer, T and Nesser, P, ‘Assessing the Islamic State's Commitment to Attacking the West’ (2015) 9 Perspectives on Terrorism 14, 20Google Scholar.

38 L Vidino, F Marone and E Entenmann, ‘Fear Thy Neighbor: Radicalization and Jihadist Attacks in the West’ (George Washington University's Program on Extremism, the Italian Institute for International Political Studies and the International Centre for Counter-Terrorism – The Hague, June 2017) <https://icct.nl/publication/fear-thy-neighbor-radicalization-and-jihadist-attacks-in-the-west/> 60–1.

39 1267 Committee, (n 23) para 83; 1267 Committee, ‘Analysis and Recommendations with Regard to the Global Threat from Foreign Terrorist Fighters’ (19 May 2015) S/2015/358 para 10.

40 Hegghammer (n 36) 11. See also 1267 Committee (n 39) para 20.

41 Leduc, R, ‘Are Returning Foreign Fighters Dangerous? Re-investigating Hegghammer's Assessment of the Impact of Veteran Foreign Fighters on the Operational Effectiveness of Domestic Terrorism in the West’ (2016) 17 Journal of Military and Strategic Studies 83Google Scholar. This is consistent with a study based on a dataset of plots of the United States: see Wright, CJ, ‘How Dangerous Are Domestic Terror Plotters with Foreign Fighter Experience? The Case of Homegrown Jihadis in the US’ (2016) 10 Perspectives on Terrorism 32Google Scholar.

42 Vidino, Marone and Entenmann (n 38) 38.

43 ibid 61.

44 United Nations Counter-Terrorism Committee Executive Directorate (n 32) 13.

45 Vidino, Marone and Entenmann (n 38) 67–71.

46 A Reed, J Pohl and M Jegerings, ‘The Four Dimensions of the Foreign Fighter Threat: Making Sense of an Evolving Phenomenon’ (ICCT Policy Brief, June 2017) <https://icct.nl/wp-content/uploads/2017/06/ICCT-Reed-Pohl-The-Four-Dimensions-of-the-Foreign-Fighters-Threat-June-2017.pdf> 7.

47 See C Ellis, ‘With a Little Help from My Friends: An Exploration of the Tactical Use of Single-Actor Terrorism by the Islamic State’ (2016) 10 Perspectives on Terrorism 41, 42–5.

48 T Mehra, ‘Foreign Terrorist Fighters: Trends, Dynamics and Policy Responses’ (ICCT Policy Brief, December 2016) <https://icct.nl/wp-content/uploads/2016/12/ICCT-Mehra-FTF-Dec2016-1.pdf> 13.

49 Nesser, P, Stenersen, A and Oftedal, E, ‘Jihadi Terrorism in Europe: The IS-Effect’ (2016) 10 Perspectives on Terrorism 3, 9Google Scholar.

50 ibid 10.

51 Zedner, L, ‘Terrorism and Counterterrorism’ in Skinns, L, Scott, M and Cox, T (eds), Risk (Cambridge University Press 2011) 111–12Google Scholar.

52 Reed, Pohl and Jegerings (n 46) 9. See generally Enders, W and Sandler, T, The Political Economy of Terrorism (2nd edn, Cambridge University Press 2011) 144CrossRefGoogle Scholar.

53 UNSC Res 2178 (24 September 2014) UN Doc S/RES/2178, operative para 6. See generally de Guttry, A, ‘The Role Played by the UN in Countering the Phenomenon of Foreign Terrorist Fighters’ in de Guttry, A, Capone, F and Paulussen, C (eds), Foreign Fighters under International Law and Beyond (TMC Asser Press 2016)CrossRefGoogle Scholar.

54 See F Ní Aoláin, ‘Report of the Special Rapporteur on the Promotion and Protection of Human Rights and Fundamental Freedoms while Countering Terrorism’ (3 September 2018) A/73/45453 paras 24–32; KL Scheppele, ‘Global Security Law and the Challenge to Constitutionalism after 9/11’ [2011] PL 353, 355–6.

55 Paulussen, C and Entenmann, E, ‘National Responses in Select Western European Countries to the Foreign Fighter Phenomenon’ in de Guttry, A, Capone, F and Paulussen, C (eds), Foreign Fighters under International Law and Beyond (TMC Asser Press 2016) 392Google Scholar.

56 C Paulussen and K Pitcher, ‘Prosecuting (Potential) Foreign Fighters: Legislative and Practical Challenges’ (ICCT Research Paper, January 2018) <https://icct.nl/wp-content/uploads/2018/01/ICCT-Paulussen-Pitcher-Prosecuting-Potential-Foreign-Fighters-Legislative-Practical-Challenges-Jan2018-1.pdf> 14. The United States is a notable exception: see Roach, K, ‘The Continued Exceptionalism of the American Response to Daesh’ in Auriel, P, Beaud, O and Wellman, C (eds), The Rule of Crisis: Terrorism, Emergency Legislation and the Rule of Law (Springer 2018)Google Scholar.

57 1373 Committee, ‘Implementation of Security Council Resolution 2178 (2014) by States Affected by Foreign Terrorist Fighters: Third Report’ (29 December 2015) S/2015/975 10.

58 Canadian Passport Order, SI/81-86, section 11.1(2). See generally Forcese, C and Roach, K, False Security: The Radicalization of Canadian Anti-Terrorism (Irwin 2015) 182Google Scholar.

59 Canadian Passport Order, SI/81-86, section 10.1.

60 M Gower, ‘Deprivation of British Citizenship and Withdrawal of Passport Facilities’ (House of Commons Library, 4 September 2014) <http://www.parliament.uk/business/publications/research/briefing-papers/SN06820/deprivation-of-british-citizenship-and-withdrawal-of-passport-facilities> 7–9. Blackbourn, J, Kayis, D and McGarrity, N, Anti-Terrorism Law and Foreign Terrorist Fighters (Routledge 2018) 73CrossRefGoogle Scholar.

61 Counter-Terrorism and Security Act 2015, section 1.

62 Australian Passports Act 2005 (Cth), section 22A, as amended by the Counter-Terrorism Legislation Amendment (Foreign Fighters) Act 2014 (Cth), section 21.

63 Australian Passports Act 2005 (Cth), section 14.

64 Blackbourn, Kayis and McGarrity (n 60) 68.

65 See Forcese and Roach (n 58) 185; N Hopkins and E MacAskill, ‘UK ‘‘Vulnerable to Terror Attacks by Jihadis Unable to Reach Syria’’’ The Guardian (23 May 2017) <https://www.theguardian.com/uk-news/2017/may/23/uk-vulnerable-to-terror-attacks-by-jihadis-unable-to-reach-syria>.

66 At least one and possibly both of the attackers who carried out the separate attacks in Canada in October 2014 were would-be foreign fighters: Forcese and Roach (n 58) 101–2. Similarly, an Australian who had his passport cancelled in 2014 to prevent his travelling to Syria later attacked two police officers in Melbourne: Byman (n 32) 82.

67 See Terrorism Prevention and Investigation Measures Act 2011, Sch 1, Pt 1.

68 Counter-Terrorism and Security Act 2015, sections 16 and 19.

69 Blackbourn, Kayis and McGarrity (n 60) 53.

70 ibid 54–5.

71 Criminal Code, RSC 1985, c C-46, section 810.011. See generally Forcese and Roach (n 58) 214–19.

72 See Anti-terrorism Act, SC 2015, c 20, Pt 3.

73 Forcese, C and Mamikon, A, ‘Neutrality Law, Anti-Terrorism and Foreign Fighters: Legal Solutions to the Recruitment of Canadians to Foreign Insurgencies’ (2015) 48 UBC Law Review 305, 332–3Google Scholar.

74 See EB v Secretary of State for the Home Department [2016] EWHC 1970 (Admin) [22].

75 Anti-Terrorism Act (No 2) 2005 (Cth), section 104.5(3).

76 Lynch, A, McGarrity, N and Williams, G, Inside Australia's Anti-terrorism Laws and Trials (NewSouth 2015) 171Google Scholar.

77 Criminal Code Act 1995 (Cth), sections 104.2, 104.4 and 104.32, as amended by Counter-Terrorism Legislation Amendment (Foreign Fighters) Act 2014 (Cth), sections 71, 73 and 86. See generally Davis, F, McGarrity, N and Williams, G, ‘Australia’ in Roach, K (ed), Comparative Counter-Terrorism Law (Cambridge University Press 2015) 681Google Scholar.

78 Lynch, McGarrity and Williams (n 76) 175.

79 Blackbourn, Kayis and McGarrity (n 60) 47–8

80 Pub L No 114–113.

81 Counter-Terrorism and Security Act 2015, sections 2–5.

82 See generally Fenwick, H, ‘Terrorism Threats and Temporary Exclusion Orders: Counter-Terror Rhetoric or Reality?’ (2017) 2017 EHRLR 247Google Scholar; Zedner, L, ‘Citizenship Deprivation, Security and Human Rights’ (2016) 18 EJML 222Google Scholar.

83 Blackbourn, Kayis and McGarrity (n 60) 89.

84 See Fenwick (n 82).

85 See generally Lenard, PT, ‘Democratic Citizenship and Denationalization’ (2018) 112 American Political Science Review 99CrossRefGoogle Scholar.

86 Pillai, S and Williams, G, ‘Twenty-First Century Banishment: Citizenship Stripping in Common Law Nations’ (2017) 66 ICLQ 521, 525–31CrossRefGoogle Scholar.

87 Attempts to extend citizenship deprivation to cover involvement in terrorism have failed: Van Waas, L, ‘Foreign Fighters and the Deprivation of Nationality: National Practices and International Law Implications’ in de Guttry, A, Capone, F and Paulussen, C (eds), Foreign Fighters under International Law and Beyond (TMC Asser Press 2016) 472Google Scholar. For explanations, see Spiro, PJ, ‘Expatriating Terrorists’ (2014) 82 FordhamLRev 2169Google Scholar.

88 See generally Pillai and Williams (n 86); Zedner (n 82). The United Nations Counter-Terrorism Committee casts doubt upon the legitimacy and effectiveness of such provisions: see 1373 Committee (n 34) para 52.

89 Blackbourn, Kayis and McGarrity (n 60) 84–5.

90 British Nationality Act 1981 section 40, as amended by Immigration Act 2014, section 66. See also R (on the application of Abdullah Muhammad Rafiqul Islam) v Secretary of State for the Home Department [2019] EWHC 2169 (Admin).

91 See text below (nn 220–23).

92 Australian Citizenship Amendment (Allegiance to Australia) Act 2015, section 33AA. The first known use of the power was to strip Khaled Sharrouf, a dual national with Lebanon, of his Australian citizenship: see J Williams, ‘ISIS Fighter's Australian Citizenship Is Revoked Under Antiterror Laws’ The New York Times (13 February 2017) <https://www.nytimes.com/2017/02/13/world/australia/citizenship-isis-khaled-sharrouf.html>.

93 Strengthening Canadian Citizenship Act, SC 2014, c 22, section 8.

94 See An Act to amend the Citizenship Act and to make consequential amendments to another Act, SC 2017, c 14.

95 See Forcese and Roach (n 58) 315–16.

96 United Nations Counter-Terrorism Committee, ‘Madrid Guiding Principles’ (23 December 2015) S/2015/939 18–19. See also C Lister, ‘Returning Foreign Fighters: Criminalization or Reintegration?’ (Brookings Institute Policy Briefing, August 2015) <http://www.brookings.edu/~/media/research/files/papers/2015/08/13-foreign-fighters-lister/en-fighters-web.pdf>.

97 According to UN estimates, 30 to 40 per cent of the 5,000 to 6,000 FTFs from Europe have returned: see 1267 Committee (n 23) para 48. Another estimate of the average return rate for the EU is 22 to 24 per cent: see Ragazzi and Walmsley (n 35) 31–2.

98 Barrett (n 31) 18–21.

99 Krähenmann (n 4) 241; Heinsch (n 3).

100 See for example R v Mohammed Kahar and others [2016] EWCA Crim 568. See generally Walker (n 13) 107–8.

101 18 USC Section 2339A(b). See also 18 USC Section 2339B(h).

102 18 USC Section 2339B(1).

103 Abrams, N, ‘A Constitutional Minimum Threshold for the Actus Reus of Crime: MPC Attempts and Material Support Offenses’ (2019) 37 Quinnipiac Law Review 199, 233–4Google Scholar. See also Center on National Security at Fordham Law, ‘Case by Case: ISIS Prosecutions in the United States’ (Center on National Security at Fordham Law, July 2016) <http://static1.squarespace.com/static/55dc76f7e4b013c872183fea/t/577c5b43197aea832bd486c0/1467767622315/ISIS+Report+-+Case+by+Case+-+July2016.pdf> 13.

104 C Doyle, ‘Terrorist Material Support: An Overview of 18 U.S.C. §2339A and §2339B’ (Congressional Research Service, 8 December 2016) <https://fas.org/sgp/crs/natsec/R41333.pdf> 1.

105 USA Freedom Act of 2015, Pub L No 114–23, section 704.

106 1373 Committee, ‘Bringing Terrorists to Justice: Challenges in Prosecutions Related to Foreign Terrorist Fighters’ (18 February 2015) S/2015/123 para 16. See also Roach (n 56) 86–7.

107 Combating Terrorism Act, SC 2013, c 9, sections 6–8.

108 Forcese and Roach (n 58) 104.

109 See R v Hersi 2014 ONSC 4414. See also Forcese and Roach (n 58) 107.

110 See text below (nn 220–52).

111 Criminal Code Act 1995 (Cth), section 119.4.

112 Lynch, McGarrity and Williams (n 76) 83.

113 Walker (n 13) 108.

114 Sarwar v R [2015] EWCA Crim 1886. See also Krähenmann (n 4) 243.

115 Serious Crime Act 2015, section 81.

116 18 USC sections 2339B(d)(1) and (d)(2). See also Doyle (n 104) 22.

117 Krähenmann (n 4) 246.

118 18 USC section 2339D.

119 Center on National Security at Fordham Law (n 103) 13.

120 Criminal Code, RSC 1985, c C-46, sections 7(3.74)-(3.75).

121 See for example Criminal Code Act 1995 (Cth), sections 15.4, 101.1(2), 101.2(4), 101.4(4), 101.5(4), 101.6(3).

122 See Counter-Terrorism Legislation Amendment (Foreign Fighters) Act 2014 (Cth), section 110. See also text below (nn 220–252).

123 Engaging in hostile activity is defined as conduct done with the intention of achieving certain violent objectives: see Criminal Code Act 1995 (Cth), section 117.1(1).

124 The two areas designated were Mosul district in Iraq and al-Raqqa province, Syria. The first remains in force; the latter was revoked on 29 November 2017: see Department of Foreign Affairs and Trade (Australia), ‘Syria’ (Smartraveller.gov.au, 23 April 2018) <http://smartraveller.gov.au/countries/middle-east/pages/syria.aspx#summary>.

125 Criminal Code Act 1995 (Cth), section 119.2(3).

126 Terrorism Act 2000, sections 58B–58C, as amended by the Counter-Terrorism and Border Security Act 2019, section 4.

127 Terrorism Act 2000, section 58B(1).

128 Terrorism Act 2000, section 58B(5) and 58B(2).

129 Heinsch (n 3) 163–6; Ragni (n 3) 1065–6.

130 Pejic, J, ‘Armed Conflict and Terrorism: There is a (Big) Difference’ in Salinas de Frías, A, Samuel, K and White, ND (eds), Counter-terrorism: International Law and Practice (Oxford University Press 2012) 173Google Scholar; Saul, B, ‘Terrorism and International Humanitarian Law’ in Saul, B (ed), Research Handbook on International Law and Terrorism (Edward Elgar 2014) 225–6Google Scholar.

131 H Tuck, T Silverman and C Smalley, ‘‘‘Shooting in the Right Direction’’: Anti-ISIS Foreign Fighters in Syria & Iraq’ (Institute for Strategic Dialogue, 2016) 47 <https://www.isdglobal.org/wp-content/uploads/2016/08/ISD-Report-Shooting-in-the-right-direction-Anti-ISIS-Fighters.pdf> 47.

132 Office of the Prosecutor, ‘Statement of the Prosecutor of the International Criminal Court, Fatou Bensouda, on the Alleged Crimes Committed by ISIS’ (8 April 2015) <https://www.icc-cpi.int/legalAidConsultations?name=otp-stat-08-04-2015-1>. See generally Heinsch (n 3) 179–80.

133 Walker (n 13) 116; B McKernan, ‘Sweden Jails Syrian Rebel who Fled Idlib after Killing Assad Soldiers’ Independent (17 February 2017) <http://www.independent.co.uk/news/world/middle-east/weden-jails-syrian-rebel-assad-soldiers-killed-murders-a7586071.html>.

134 See Walker (n 13) 109; Blackbourn, Kayis and McGarrity (n 60) 16–21.

135 United Nations Counter-Terrorism Committee, ‘Addendum to the Guiding Principles on Foreign Terrorist Fighters’ (28 December 2018) S/2018/1177 para 44.

136 Paulussen and Pitcher (n 56) 29; E Lichtblau, ‘F.B.I. Steps Up Use of Stings in ISIS Cases’ The New York Times (7 June 2016) <http://www.nytimes.com/2016/06/08/us/fbi-isis-terrorism-stings.html>.

137 But not unproblematically: see Aaronson, T, The Terror Factory (Ig Publishing 2014)Google Scholar.

138 1373 Committee (n 106) paras 26–27.

139 K Hardy, ‘Why Is It So Difficult to Prosecute Returning Fighters?’ (The Conversation, 5 June 2017) <https://theconversation.com/why-is-it-so-difficult-to-prosecute-returning-fighters-78596>; Mehra (n 48) 18.

140 1373 Committee (n 106) para 24.

141 Hardy (n 139).

142 See generally Walker (n 13) 109.

143 Paulussen and Pitcher (n 56) 26–9.

144 UNSC Res 2396 (21 December 2017) UN Doc S/RES/2396.

145 Walker (n 13) 97. See also HC Deb 1 September 2014, vol 585, cols 23–27; Home Affairs Committee, Counter-terrorism: foreign fighters (HC 2014–15, 933).

146 B Boutin et al., ‘The Foreign Fighters Phenomenon in the European Union’ (ICCT Research Paper, April 2016) <http://icct.nl/wp-content/uploads/2016/03/ICCT-Report_Foreign-Fighters-Phenomenon-in-the-EU_1-April-2016_including-AnnexesLinks.pdf> Annex 1: Methodology.

147 A Reed and J Pohl, ‘Disentangling the EU Foreign Fighter Threat: The Case for a Comprehensive Approach’ (RUSI Newsbrief, 10 February 2017) <https://rusi.org/sites/default/files/nb_vol.37_no1_pohl_and_reed.pdf> 1; Boutin et al. (n 146) 13.

148 UNSC, ‘7272 Meeting’ (24 September 2014) UN Doc S/PV.7272 <http://www.un.org/en/ga/search/view_doc.asp?symbol=S/PV.7272>.

149 See for example HC Deb 1 September 2014, vol 585, cols 23–27; Home Affairs Committee (n 145).

150 See also de Roy van Zuijdewijn, J, ‘The Foreign Fighters’ Threat: What History Can (not) Tell Us’ (2014) 8 Perspectives on Terrorism 59, 61Google Scholar.

151 See generally Hoffman, B, Inside Terrorism (3rd edn, Columbia University Press 2017) 21–36CrossRefGoogle Scholar.

152 See generally Saul, B, ‘Defining Terrorism: A Conceptual Minefield’ in Chenoweth, E et al. (eds), The Oxford Handbook of Terrorism (Oxford University Press 2019)Google Scholar.

153 Richardson, L, What Terrorists Want (Random House 2006) 6Google Scholar; Hoffman (n 151) 36–7.

154 Watkin, K, Fighting at the Legal Boundaries: Controlling the Use of Force in Contemporary Conflict (Oxford University Press 2016) 180CrossRefGoogle Scholar.

155 ibid 191.

156 Hoffman (n 151) 37.

157 Richardson (n 153) 4.

158 Hoffman (n 151) 37.

159 English, R, Terrorism: How to Respond (Oxford University Press 2009) 12Google Scholar; Watkin (n 154) 190.

160 Cronin, AK, ‘What Is Really Changing? Change and Continuity in Global Terrorism’ in Strachan, H and Scheipers, S (eds), The Changing Character of War (Oxford University Press 2011) 139Google Scholar.

161 Hoffman (n 151) 37.

162 See Watkin (n 154) 197–208; Hoffman (n 151) 38.

163 Cronin, AK, ‘ISIS Is Not a Terrorist Group: Why Counterterrorism Won't Stop the Latest Jihadist Threat’ (2015) 94 Foreign Affairs 88Google Scholar.

164 This is characteristic of counterterrorism legislation more generally: see Ashworth, A and Zedner, L, Preventive Justice (Oxford University Press 2014) 171–95CrossRefGoogle Scholar.

165 See generally Jarvis, L and Legrand, T, ‘The Proscription or Listing of Terrorist Organisations: Understanding, Assessment, and International Comparisons’ (2018) 30 Terrorism and Political Violence 199, 201CrossRefGoogle Scholar.

166 Krähenmann (n 4) 240.

167 Saul (n 130) 213.

168 Krähenmann (n 11) 63.

169 The messy reality of a zone of armed conflict further complicates matters. The allegiances of an individual might shift—for example, United States Army veteran Eric Harroun originally joined the undesignated Free Syria Army but later joined al-Nusra, a designated FTO: see Krähenmann (n 4) 247.

170 D Richemond-Barak and V Barber, ‘Foreign Volunteers or Foreign Fighters? The Emerging Legal Framework Governing Foreign Fighters’ (Opinio Juris, 6 May 2016) <http://opiniojuris.org/2016/05/06/foreign-volunteers-or-foreign-fighters-the-emerging-legal-framework-governing-foreign-fighters/>. See also Forcese and Mamikon (n 73) 309.

171 Tuck, Silverman and Smalley (n 131) 8. Of those with known employment backgrounds, a significant number previously served in national militaries: ibid 10.

172 ibid 10.

173 ibid 16.

174 The United States (18 USC Section 2339B), Canada (Criminal Code, section 83.18(1)) and Australia (Criminal Code, section 102.7(1)) have applicable offences based on providing support to a terrorist group. In the United Kingdom, the likely offence would be section 5 of the Terrorism Act 2006, which does not depend on links to a terrorist group: see for example R v Mohammed Kahar and others (n 100) [129]–[144].

175 One possible complicating factor is that the YPG has affiliations with the PKK: see Paulussen and Pitcher (n 56) 25.

176 Krähenmann (n 11) 61; Sassòli, M, ‘Terrorism and War’ (2006) 4 JICJ 959, 959Google Scholar.

177 Saul (n 130) 230; Ragni (n 3) 1066–7.

178 Pejic, J, ‘Terrorist Acts and Groups: A Role for International Law?’ (2005) 75 BYBIL 71, 73Google Scholar.

179 Krähenmann (n 4) 238.

180 UNSC Res 1373 (28 September 2001) UN Doc S/RES/1373.

181 Saul, B, ‘The Legal Death of Rebellion: Counterterrorism Laws and the Shrinking Legal Freedom of Violent Political Resistance’ in Lazarus, L and Goold, B (eds), Security and Human Rights (2nd edn, Hart 2019) 332Google Scholar.

182 Ní Aoláin (n 54) para 47.

183 See Roach, K, ‘The post-9/11 Migration of Britain's Terrorism Act 2000’ in Choudhry, S (ed), The Migration of Constitutional Ideas (Cambridge University Press 2006)Google Scholar. See also Greene, A, ‘Defining Terrorism: One Size Fits All?’ (2017) 66 ICLQ 411CrossRefGoogle Scholar.

184 R v Gul [2013] UKSC 64 [61]–[62].

185 The United Nations Counter-Terrorism Committee has cautioned against reliance on overly broad definitions of terrorism to fulfil obligations under UNSCR 2178: see 1373 Committee (n 34) para 73. See also United Nations Counter-Terrorism Committee (n 135) Guiding Principle 41.

186 D Anderson, ‘The Terrorism Acts in 2013’ (July 2014) <https://terrorismlegislationreviewer.independent.gov.uk/wp-content/uploads/2014/07/Independent-Review-of-Terrorism-Report-2014-print2.pdf> [10.36].

187 Even putting aside section 1(3), which provides that where the use or threat of action involves the use of firearms or explosives, the requirement that the action be designed to influence a government or intimidate the public is deemed to be met. See also R v F [2007] QB 960 [28].

188 Terrorism Act 2000, section 1(4). The same is true of the Canadian and Australian definitions: see Criminal Code, RSC 1985, c C-46, section 83.01(1)(b); Criminal Code Act 1995 (Cth), section 100.1.

189 Saul (n 181) 324. See also Greene (n 183) 426–7.

190 R v F (n 187) [32]; R v Gul (n 184) [26]. Accordingly, the argument raised by two returnees that their activities against Syrian government forces as part of the Free Syria Army was ‘noble cause terrorism’ was rejected: see Sarwar v R (n 114) [41]–[43].

191 Australia's definition is the same in this respect: see Saul (n 181) 336. Canada's definition does include an armed conflict exception: Criminal Code, RSC 1985, c C-46, section 83.01(1). In the case of ISIL at least, the requirement of showing compliance with IHL presents a significant obstacle: see Forcese and Mamikon (n 73) 329–30. As for the United States, none of the various definitions of terrorism and similar terms relevant to the material support offences explicitly mention armed conflict: see 18 USC Section 2339B(g)(6) (defining ‘terrorist organization’), 22 USC Section 2656f(d)(2) (defining ‘terrorism’) and 8 USC Section 1182(a)(3)(B)(iii) (defining ‘terrorist activity’).

192 R v Gul (n 184).

193 Krähenmann (n 4) 243.

194 Sassòli (n 176) 971; Pejic (n 178) 75.

195 Saul (n 181) 337.

196 R v Gul (n 184) [33]. See also Greene (n 183) 430–1.

197 Paulussen and Pitcher (n 56) 24–5; Richemond-Barak and Barber (n 170).

198 Paulussen and Pitcher (n 56) 24.

199 Blackbourn, Kayis and McGarrity (n 60) 24.

200 The prosecution of James Matthews was dropped for lack of evidence. In the other case, the trial judge directed that Aidan James be acquitted of preparation of terrorist acts, and the jury was unable to reach a verdict on other charges: see L Dearden, ‘Aidan James: British Man Who Fought against Isis in Syria Faces Retrial on Terror Charges’ Independent (16 April 2019) <https://www.independent.co.uk/news/uk/crime/aidan-james-trial-isis-syria-court-old-bailey-pkk-islamic-state-a8872221.html>.

201 R v Gul (n 184) [36].

202 Seger, P, ‘The Law of Neutrality’ in Clapham, A and Gaeta, P (eds), The Oxford Handbook of International Law in Armed Conflict (Oxford University Press 2014) 253Google Scholar.

203 E Chadwick, ‘Neutrality Revised’ (2013) 22 NottLJ 41, 41; Seger (n 202) 249. Wani, K, Neutrality in International Law: From the Sixteenth Century to 1945 (Taylor & Francis 2017) 33–4CrossRefGoogle Scholar.

204 Seger (n 202) 258; Oppenheim, L, International Law. A Treatise. Volume II (of 2): War and Neutrality (2nd edn, Longmans 1912) 376Google Scholar. See generally Brownlie, I, ‘Volunteers and the Law of War and Neutrality’ (1956) 5 ICLQ 570, 570–1CrossRefGoogle Scholar.

205 Fenwick, CG, The Neutrality Laws of the United States (Carnegie Endowment for International Peace 1913) 11–12Google Scholar. See also Oppenheim (n 204) 375–7.

206 Carter, A, ‘Liberalism and the Obligation to Military Service’ (1998) 46 Political Studies 68, 70CrossRefGoogle Scholar; Irving, H, Citizenship, Alienage, and the Modern Constitutional State: A Gendered History (Cambridge University Press 2016) 115CrossRefGoogle Scholar.

207 Thomson, JE, Mercenaries, Pirates, and Sovereigns (Princeton University Press 1994) 82Google Scholar.

208 Arielli (n 2) 27.

209 Wani (n 203) 60.

210 Thomson, JE, ‘State Practices, International Norms, and the Decline of Mercenarism’ (1990) 34 International Studies Quarterly 23, 34CrossRefGoogle Scholar.

211 Act of June 5, 1794, ch 50, 1 Stat 381. See also Malet (n 9) 35.

212 Lobel, J, ‘Rise and Decline of the Neutrality Act: Sovereignty and Congressional War Powers in United States Foreign Policy, The’ (1983) 24 HarvIntlLJ 1, 24–5Google Scholar; Thomson (n 207) 88.

213 See Fenwick (n 205) 174–5 (reproducing the 1794 Act). The current provisions are now found in 18 USC sections 958–960.

214 ibid 62. See also Garcia-Mora, MR, ‘International Law and the Law of Hostile Military Expeditions’ (1958) 27 FordhamLRev 309, 315Google Scholar.

215 Thomson (n 210) 39.

216 Foreign Enlistment Act 1870, section 4.

217 ibid section 5. See also Fenwick (n 205) 128.

218 Foreign Enlistment Act, RSC 1985, c F-28.

219 ibid sections 3–5. See also Wentzell, T, ‘Canada's Foreign Fighters: The Foreign Enlistment Act and Related Provisions in the Criminal Code’ (2016) 63 CrimLQ 102, 108Google Scholar.

220 Crimes (Foreign Incursions and Recruitment Act) 1978 (Cth), sections 6–7 (repealed).

221 ibid sections 8–9 (repealed).

222 See Forcese and Mamikon (n 73); Wentzell (n 219) 121–2; D Anderson, ‘The Terrorism Acts in 2014’ (September 2015) <https://terrorismlegislationreviewer.independent.gov.uk/wp-content/uploads/2015/09/Terrorism-Acts-Report-2015-Print-version.pdf> [8.21]. An alternative view is that pure foreign fighting ought not be regulated by the home State at all: see Webb, AK, ‘‘‘Swanning back in’’? Foreign Fighters and the Long Arm of the State’ (2017) 21 Citizenship Studies 291, 304CrossRefGoogle Scholar.

223 See Counter-Terrorism Legislation Amendment (Foreign Fighters) Act 2014 (Cth), section 110.

224 Criminal Code Act 1995 (Cth), section 119.2–119.3, as amended by Counter-Terrorism Legislation Amendment (Foreign Fighters) Act 2014 (Cth), section 110.

225 Terrorism Act 2000, sections 58B–58C, as amended by the Counter-Terrorism and Border Security Act 2019, section 4.

226 M Lloydd, ‘Retrieving Neutrality Law to Consider ‘‘Other’’ Foreign Fighters Under International Law’ (European Society of International Law 2017 Research Forum, 29 September 2017) <https://papers.ssrn.com/sol3/papers.cfm?abstract_id=3045274> 17. See also Department of Foreign Affairs and Trade (Australia) (n 124).

227 See Criminal Code Act 1995 (Cth), section 119.1(4).

228 See Joint Committee on Human Rights, Second Legislative Scrutiny Report: Counter-Terrorism and Border Security Bill (2017–19, HL195, HC 1616) [64].

229 See J Renwick, ‘Sections 119.2 and 119.3 of the Criminal Code: Declared Areas’ (September 2017) <https://www.inslm.gov.au/sites/default/files/files/declared-areas.pdf> [5.32]–[5.33]; Parliamentary Joint Committee on Intelligence and Security, Review of the ‘Declared Area’ Provisions (February 2018) <https://www.aph.gov.au/Parliamentary_Business/Committees/Joint/Intelligence_and_Security/DeclaredArea/Report> [2.77]–[2.79]; Joint Committee on Human Rights (n 228) [58]–[66].

230 Renwick (n 229) [9.7]; Parliamentary Joint Committee on Intelligence and Security (n 229) [2.80].

231 Parliamentary Joint Committee on Human Rights, Examination of legislation in accordance with the Human Rights (Parliamentary Scrutiny) Act 2011 Bills introduced 30 September–2 October 2014 Legislative Instruments received 13–19 September 2014 (October 2014) <http://www.aph.gov.au/~/media/Committees/Senate/committee/humanrights_ctte/reports/2014/14_44/14th%20report%20FINAL.pdf> [1.204], [1.182].

232 See Criminal Code Act 1995 (Cth), sections 119.2(3).

233 Renwick (n 229) [8.32]; Parliamentary Joint Committee on Intelligence and Security (n 229) [2.83]–[2.88].

234 Joint Committee on Human Rights, (n 228) [59]–[61]; R Taylor, ‘Counter-Terrorism and Border Security Bill HL Bill 131 of 2017–19’ (House of Lords Library Briefing, 3 October 2018) <https://researchbriefings.parliament.uk/ResearchBriefing/Summary/LLN-2018-0097> 7–8.

235 See HL Deb 15 January 2019, vol 795, col 137; HC Deb 22 January 2019, vol 653, col 167.

236 Terrorism Act 2000, sections 58B(2), 58B(3)(b).

237 Ibid, section 58B(4)–(6). Interestingly, the government stated that adding this list of legitimate purposes for travel ‘would not materially affect the operation of the offence’, and that there was little difference in police investigating whether an individual might be able to rely on a defence of reasonable excuse or whether one of the exclusions to the offence might apply: see HL Deb 15 January 2019, vol 795, col 137.

238 See 1373 Committee (n 34) para 2; Independent International Commission of Inquiry on the Syrian Arab Republic, ‘Report of the Independent International Commission of Inquiry on the Syrian Arab Republic’ (5 February 2015) A/HRC/28/69 paras 125–127.

239 Lloydd (n 226) 23.

240 ibid 23–4.

241 Forcese and Mamikon (n 73) 357.

242 See text below (nn 251–53).

243 In the case of the Australian offence, this assumes that the defendant succeeds in discharging the evidential burden and is able to rely on one of the specified legitimate purposes.

244 Lloydd (n 226) 4.

245 Forcese and Mamikon (n 73) 359.

246 Lloydd (n 226) 4.

247 Forcese and Mamikon (n 73) 359; Blackbourn, J and Walker, C, ‘Interdiction and Indoctrination: The Counter-Terrorism and Security Act 2015’ (2016) 79 MLR 840, 856CrossRefGoogle Scholar.

248 Tuck, Silverman and Smalley (n 131) 49–50. In which case, it is arguable that the person is not actually ‘foreign’ to the conflict: see text above (nn 10–12).

249 Parliamentary Joint Committee on Intelligence and Security (n 229) [2.19].

250 Lloydd (n 226) 11.

251 Criminal Code Act 1995 (Cth), sections 119.1(4) and 119.8.

252 Lloydd (n 226) 18.

253 Which Forcese and Mamikon suggest are properly ‘matters of executive judgment’: Forcese and Mamikon (n 73) 359.

254 See Layeb, A, ‘Mercenary Activity: United States Neutrality Laws and Enforcement’ (1989) 10 NYL Sch J Int'l & Comp L 269, 293Google Scholar; Green, LC, ‘The Status of Mercenaries in International Law’ (1979) 9 ManitobaLJ 201, 212–13Google Scholar.

255 Blackbourn and Walker (n 247) 855.

256 Forcese and Mamikon (n 73) 353. The explanation lies in the archaic nature of the British and Canadian legislation, which reflects a dated view of international relations and war, particularly civil war: see Report of the Committee of Privy Counsellors Appointed to Inquire into the Recruitment of Mercenaries (Cm 6569, 1976) [26]; Forcese and Mamikon (n 73) 352.

257 Arielli (n 2) 125.