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Judicial constitutional comparativism at the UK Supreme Court

  • Christina Lienen (a1)


In 2008, Lord Reed in his paper ‘Foreign precedents and judicial reasoning: the American debate and British practice’ noted the lack of full scholarly consideration of judicial comparativism in the UK. Ten years later, judicial reference to foreign judgments is still a very common phenomenon in this jurisdiction, however very little has been written about it. This paper assesses the UK Supreme Court's constitutional law jurisprudence in light of the main themes and arguments underlying the international debate concerning judicial comparativism. I argue that: (i) the use of foreign law is constitutionally legitimate where clear statutory language is respected; (ii) transferability concerns are mitigated by the interwovenness of the global common law system; and (iii) methodology concerns are mitigated by the UK Supreme Court's flexible, humble approach, which applies careful scrutiny to the foreign authorities put before it. Foreign judgments, I conclude, are never followed blindly or arbitrarily, and perhaps this is why there is no domestic debate about judicial comparativism, not even in the constitutional sphere.


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I would like to thank Richard Rawlings, Cheryl Saunders, Alison Young and the journal’s anonymous reviewers for their very helpful comments on an earlier version of this paper.



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1 Reed, RForeign precedents and judicial reasoning: the American debate and British practice’ (2008) 124 Law Quarterly Review 253.

2 Despite some authors detecting a trend, see for example Slaughter, AMA typology of transjudicial communication’ (1994) 29 University of Richmond L Rev 99; Slaughter, AM A New World Order (Princeton: Princeton University Press, 2004); Rosenfeld, M The Identity of the Constitutional Subject: Selfhood, Citizenship, Culture, and Community (Abingdon: Routledge, 2009) pp 246247, it is not clear whether the use of foreign law has actually increased: Hirschl, RThe view from the bench – where the comparative judicial imagination travels’ in Comparative Matters: The Renaissance of Comparative Constitutional Law (Oxford: Oxford University Press, 2014) p 37.

3 Reed, above n 1, at 269.

4 Reed, above n 1, at 253.

5 R Reed ‘Comparative law in the Supreme Court of the United Kingdom’, Centre for Private Law, University of Edinburgh, 13 October 2017.

6 The most famous example being Fairchild v Glenhaven Funeral Services Ltd [2002] UKHL 22, [2003] 1 AC 32, which was criticised for its extensive reference to foreign law in Weir, TMaking it more likely v Making it happen’ [2002] CLJ 519 at 521; see also D & F Estates Ltd v Church Commissioners for England [1989] AC 177, which referred to American law, and White v Jones [1995] 2 AC 207, which relied on German law. For an overview see Stanton, KComparative law in the House of Lords and Supreme Court’ (2013) 42(3) Common Law World Review 269.

7 See for example the seminal Hadley v Baxendale [1854] 9 Ex Ch 341, which was heavily influenced by American law and the French Civil Code.

8 See for example the landmark decision in R v Jogee [2016] UKSC 8, in which Australian law featured heavily.

9 Examples include Guardian News & Media Ltd v City of Westminster Magistrates’ Court [2012] EWCA Civ 420, Moohan and Another v The Lord Advocate [2014] UKSC 67 and A v British Broadcasting Corporation [2014] UKSC 25.

10 See M Nounckele ‘De la légitimité de la comparaison par les juges – etude de la jurisprudence de la House of Lords de 1996 à 2005’ (study prepared at the University of Louvain-la-Neuve, 2011).

11 A very notable exception to this in the context of human rights jurisprudence is Tyrrell, Hélène Human Rights in the UK and the Influence of Foreign Jurisprudence (Oxford: Hart, 2018).

12 For an example of the latter see A and Others v Secretary of State for the Home Department [2005] UKHL 71.

13 Saunders, CComparative constitutional law in the courts: is there a problem?’ (2006) 59(1) CLP 91 at 99.

14 I do not distinguish between formal or written constitutions and uncodified ones, see ibid, at 98 on this point.

15 R (on the application of F) and Thompson v Secretary of State for the Home Department [2010] UKSC 17 at [57].

16 Bank Mellat v Her Majesty's Treasury (No 2) [2013] UKSC 39 at [68] (Lord Reed, dissenting).

17 R v Gul [2013] UKSC 64 at [61] and [62].

18 HJ (Iran) v Secretary of State for the Home Department [2010] UKSC 31. Note that direct applications are rare and, arguably, this case is more about a domestic interpretation of international law.

19 Choudhry, SMigration as a new metaphor in comparative constitutional law’ in Choudhry, S (ed) The Migration of Constitutional Ideas (Cambridge: Cambridge University Press, 2002) p 1.

20 Lael Weis compares the influence of the originalism doctrine in Australia and the United States in What comparativism tells us about originalism’ (2013) 11(4) International Journal of Constitutional Law 842.

21 Other examples more limited in scope include Mance, JForeign laws and languages’ in Burrows, A, Johnston, D and Zimmermann, R (eds) Judge and Jurist: Essays in Memory of Lord Rodgers of Horsferry (Oxford: Oxford University Press, 2013); R Walker ‘Developing the common law: how far is too far?’ Victoria Law Foundation's Annual Oration, Banco Court, Melbourne, September 2012; R Toulson ‘International influence on the common law’ The London Common Law and Commercial Bar Association, London, 11 November 2014. See also Goff, RJudge, jurist and legislature’ (1986) 2(1) The Denning Law Journal 79.

22 Goff, above n 21, at 94.

23 Toulson, above n 21, at para 42.

24 This is in line with the underlying sentiment in common law constitutional rights cases, see for example A v British Broadcasting Corporation, above n 9, and Kennedy v The Charity Commission [2014] UKSC 20.

25 Even those are written from a comparative, rather than a purely domestic angle: see McCrudden, CCommon law of human rights? Transnational judicial conversations on constitutional rights’ (2000) 20 OJLS 499; Fredman, SForeign fads or fashions? The role of comparativism in human rights law’ (2015) 64 ICLQ 631.

26 The latest contribution on this phenomenon in the context of adjudication based on the rule of law and the separation of powers is Wheatle, S Principled Reasoning in Human Rights Adjudication (Oxford: Hart, 2017) ch 7.

27 Hirschl, above n 2, p 37.

28 Zhou, HR ‘A contextual defense of “comparative constitutional common law”’ (2014) 12(4) IJCL 1034.

29 Glenn, HP On Common Laws (Oxford: Oxford University Press, 2005) p 69.

30 This was confirmed by an interview with Supreme Court Justices: see Bell, JComparative law in the Supreme Court 2010–11’ (2012) 1(2) CJICL 20. For a slightly different interpretation of the word ‘persuasive’ see Reed, above n 1, at 269.

31 Mak, EComparative law before the Supreme Courts of the UK and the Netherlands’ in Andenas, M and Fairgrieve, D (eds) Courts and Comparative Law (Oxford: Oxford University Press, 2015) p 411.

32 Ibid, p 416. Note that this is different from other jurisdictions where foreign law may very well be taken into account, but will not be specifically referred to in a judgment.

33 The Conservatives in their 2015 manifesto pledged to scrap the HRA 1998 and replace it with a ‘British Bill of Rights’, details of which have not crystallised beyond what was originally formulated in the Conservatives’ 2014 proposal, which has been unfavourably received: ‘Protecting human rights in the UK, The Conservatives’ proposal for changing Britain's human rights laws’ (2014). Two years ago, the then Lord Chancellor Elisabeth Truss announced that the Government would go ahead with their plans to honour their manifesto pledge, however last year it was announced that any legislative changes to the UK's human rights regime would be put on hold until after Brexit. This was confirmed by the Conservatives’ manifesto for the 2017 General Election.

34 For an overview see Stone, AComparativism in constitutional interpretation’ (2009) UMelbLRS 15.

35 For a comprehensive account of the debate and its implication for constitutional law decisions by the US Supreme Court see the illuminating Simon, SAThe Supreme Court's use of foreign law in constitutional rights cases’ (2013) 1(2) Journal of Law and Courts 279.

36 In the United States, the most famous of all exchanges on the topic is the Conversation between Justices Scalia and Breyer, see ‘A conversation between US Supreme Court justices. The relevance of foreign legal materials in US constitutional cases: a conversation between Justice Antonin Scalia and Justice Stephen Breyer’, Washington College of Law, 13 January 2005.

37 For example, the late Lord Toulson was undoubtedly one of the most prolific judicial comparativists, and some of his judgments will be discussed in this paper.

38 Junius Letter (London Evening Post, 1770) reprinted in Heward, E Lord Mansfield (London: B Rose, 1979) p 129.

39 The leading scholarly works include Jackson, VCConstitutional comparisons: convergence, resistance, engagement’ (2005) 119 HLR 109; Alford, RPMisusing international sources to interpret the constitution’ (2004) 98 American J Int Law 57.

40 Judicial comparativism is a phenomenon found in almost all prominent jurisdictions, and it has triggered intensive academic exploration, see for example Law, DSJudicial comparativism and judicial diplomacy’ (2015) 163(4) University of Pennsylvania Law Review 927, where practices at the Japanese Supreme Court, the Korean Constitutional Court, the Taiwanese Constitutional Court, and the Hong Kong Court of Final Appeal are scrutinised.

41 See for example TK Graziano ‘It is legitimate and beneficial for judges to compare?’ in Andenas and Fairgrieve, above n 31.

42 Waldron, JPartly laws common to all mankind’ in Foreign Law in American Courts (New Haven: Yale University Press, 2012).

43 Rosenfeld, M and Sajó, A (eds) The Oxford Handbook of Comparative Constitutional Law (Oxford: Oxford University Press, 2012) Introduction.

44 Fredman, above n 25, at 632, citing Justice Scalia in Roper v Simmons (2005) 543 US 551 (US Supreme Court) at [627].

45 A Cohler and others (eds and trans) Charles de Secondat, Baron de Montesquieu, The Spirit of Laws (1989) p 8: ‘the political and civil laws of each nation […] should be so appropriate to the people for whom they are made that it is very unlikely that the laws of one nation can suit another’.

46 Flaherty, MSJudicial globalization in the service of self-government’ (2006) 20(4) Ethics & International Affairs 477 at 479.

47 R Hirschl ‘On the blurred methodological matrix of comparative constitutional law’ in Choudhry (ed), above n 19, p 41.

48 Baudenbacher, CJudicial globalization: new development or old wine in new bottles’ (2003) 38(3) Texas International Law Journal 505 at 505.

49 Slaughter, AMA typology of transjudicial communication’ (1994) 29 University of Richmond L Rev 99 at 102.

50 Wheatle, above n 26, p 149.

51 Barak, A The Judge in A Democracy (Princeton: Princeton University Press, 2006) p 198. See also Printz v United States 521 US 898.

52 Mendes, CHA global constitution of rights: the ethics, the mechanics and the geopolitics of comparative constitutional law’ in Baxi, U, Viljoen, F and Velhena, O (eds) Transformative Constitutionalism: Comparing the Apex Courts of Brazil, India and South Africa (Pretoria University Press, 2014) p 55.

53 In the American context, the most vocal supporter of the argument used to be the late Justice Scalia, see for example Commentary’ (1996) 40 St Louis University Law Journal 1119; see also Larsen, ZDiscounting foreign imports: foreign authority in constitutional interpretation and the curb of popular sovereignty’ (2009) 45 Willamette Law Review 767.

54 ‘A conversation’, above n 36.

55 Tushnet, M Weak Courts, Strong Rights: Judicial Review and Social Welfare Rights Comparative Constitutional Law (Princeton: Princeton University Press, 2008) p 10.

56 Legrand, PEuropean legal systems are not converging’ (1996) 45 ICLQ 52 at 56.

57 ‘A conversation’, above n 36.

58 Graziano tries to refute this by saying that the existence of the private international law regime demonstrates a manifestation of the belief that national judges can access and grasp foreign law in a reliable and meaningful way: ‘It is legitimate and beneficial for judges to compare?’ Andenas and Fairgrieve, above n 31, p 32. However, this point is weakened by the fact that in private international law cases there is a much higher level of scrutiny of foreign law.

59 Chief Justice Roberts, United States Senate Judiciary Committee (Hearing on the Nomination of John Roberts to be Chief Justice of the Supreme Court, Transcript, Day Two, 13 September 2005).

60 Saunders, above n 13, referencing the Code of Conduct of the Bar of England and Wales, para 710(c).

61 Reed, above n 1, combined these two aspects under the heading ‘methodology’.

62 ‘A conversation’, above n 36, at 522–525.

63 See Burnham, MACultivating a seedling charter: South Africa's court grows its constitution’ (1997) 3 Michigan Journal of Race and Law 29.

64 Zhou, above n 28, at 1038.

65 McCrudden, above n 25, at 502–503.

66 Smits, JMComparative law and its influence on national legal systems’ in Reimann, M and Zimmermann, R (eds) The Oxford Handbook of Comparative Law (Oxford: Oxford University Press, 2006) pp 526527. For a similar argument focusing on the relationship between authority and substantive reasons see Summers, RSTwo types of substantive reasons: the core of a theory of common law justification’ (1977) 63 Cornell Law Review 707.

67 Derbyshire County Council v Times Newspapers [1993] AC 534 at 548D.

68 This function was identified as one of the main ones by UKSC justices in interviews, see Mak, above n 31, p 416.

69 Saunders, above n 13, at 99–100.

70 Bingham, T Widening Horizons (Cambridge: Cambridge University Press, 2010) pp 7–8.

71 Guardian News, above n 9.

72 Independent Newspapers (Pty) Ltd v Minister for Intelligence Services 2008 (5) SA31 at [43].

73 Guardian News, above n 9, at [88] (emphasis added).

74 Saunders, above n 13, at 108.

75 For example, there is not even a Practice Direction at the UKSC level.

76 Apart from being a problematic suggestion as a matter of principle.

77 R (on the application of Miller and Another) v Secretary of State for Exiting the European Union [2017] UKSC 5, particularly at [252] and [43].

78 Some would argue, by abstaining from laying down the law in a way that goes far beyond the facts of the particular case before it: see for example J Finnis ‘Judicial power: past, present and future’, Gray's Inn Hall Lecture, 20 October 2015, pp 4–5.

79 The formal description of this Diceyan account was followed in British Railways Board v Pickin [1974] AC 765, however it is today considered much more nuanced, see Elias LJ ‘Annual Lord Renton Lecture’, 24 November 2009.

80 Saunders, above n 13, at 109.

81 Choudhry, above n 19, p 4. The post-WWII era has seen the emergence of a constitutional model characterised by cross-fertilisation, see L Weinrib ‘The postwar paradigm and American exceptionalism’ in Choudhry, above n 19.

82 Allan, TRS Constitutional Justice: A Liberal Theory of the Rule of Law (Oxford: Oxford University Press, 2001) Preface.

83 Ibid, p 4.

84 For an overview of this theory see Poole, TBack to the future? Unearthing the theory of common law constitutionalism’ (2003) 23(3) OJLS 435.

85 Griffith, JGAThe political constitution’ (1979) 42 MLR 1.

86 Tomkins, A Our Republican Constitution (Oxford: Hart, 2005). See also Ekins, RLegislative freedom in the United Kingdom’ (2017) 133 Law Quarterly Review 582.

87 R (on the application of UNISON) v Lord Chancellor [2017] UKSC 51; see also R v Lord Chancellor, ex p Witham [1998] QB 575 and R v Secretary of State for the Home Department, ex p Leech [1994] QB 198.

88 Council of Civil Service Unions v Minister for the Civil Service [1985] AC 374; Moules, RJudicial review of prerogative orders in council: recognising the constitutional reality of executive legislation’ (2008) 67(1) CLJ 12.

89 Goff, above n 21, at 83.

90 R (Nicklinson and Another) v Ministry of Justice ; R (AM) v DPP [2014] UKSC 38.

91 J Goldsworthy ‘Questioning the migration of constitutional ideas: rights, constitutionalism and the limits of convergence’ in Choudhry, above n 19, p 119.

92 M Elliott ‘The right to die: deference, dialogue and the division of constitutional authority’ Public Law For Everyone, 26 June 2016. See also Young, A Democratic Dialogue and the Constitution (Oxford: Oxford University Press, 2017) p 211.

93 Fredman, above n 25, at 633; see also Hoffmann, LHuman rights and the House of Lords’ (1999) 62 MLR 159.

94 R Toulson ‘International influence on the common law’, The London Common Law and Commercial Bar Association, London, 11 November 2014, para 41.

95 Ackermann, LWHConstitutional comparativism in South Africa: a response to Sir Basil Markesinis and Jörg Fedtke’ (2005) 80 Tulane Law Review 169 at 184.

96 Hirschl, above n 2, p 76.

97 For a closer exploration of the role of the former Empire and colonies in this regard see Wheatle, above n 26, pp 150–163.

98 Hayne, KMThe High Court of Australia and the Supreme Court of the United Kingdom: the continued evolution of legal relationships’ (2012) 1(2) CJICL 13 at 13.

99 Parker v The Queen (1963) 111 CLR 610.

100 Hayne, above n 98, at 15.

101 Harris, JWThe Privy Council and the common law’ (1990) 106 Law Quarterly Review 574 at 581.

102 Borough of Duryea, Pa v Guarnieri (131 S Ct 2488, 2498-99 [2011]).

103 AG (Nova Scotia) v MacIntyre [1982] 1 SCR 175.

104 Scott v Scott [1913] AC 417.

105 McPherson v McPherson [1936] AC 177.

106 Bobek, M Comparative Reasoning in European Supreme Courts (Oxford: Oxford University Press, 2013).

107 Guardian News, above n 9, at [30].

108 R v Chaytor [2010] UKSC 52.

109 Bell, above n 30, at 23.

110 Harris, above n 101, at 574 commenting on Cassell & Co Ltd v Broome [1972] AC 1027 (Lord Diplock).

111 A v British Broadcasting Corporation, above n 9, at [40] (emphasis added).

112 Moohan and Another v The Lord Advocate [2014] UKSC 67 at [36].

113 R (Jackson) v Attorney General [2005] UKHL 56, [2006] 1 AC 262.

114 Reed, above n 1, at 272–273.

115 Reed, above n 5, pp 6–11.

116 Belhaj v Straw [2017] UKSC 3.

117 It would be worthwhile to explore in depth what may be another nuance or dimension of judicial comparativism, namely the bolstering of national law through the exchange of ideas to ‘unite’ against supranational entities.

118 R Carnwath ‘People and principle in the developing law’, Eighth Biennial Conference on the Law of Obligations: Revolutions in Private Law, University of Cambridge, 19 July 2016, p 2.

119 HJ (Iran), above n 18.

120 R v Horncastle [2009] UKSC 14. Note that this is comparable to what Wheatle brands reputational value, above n 26, p 149.

121 Michael and Others v The Chief Constable of South Wales Police and Another [2015] UKSC 2.

122 Montgomery v Lanarkshire Health Board [2015] UKSC 11. The quote is taken from Reed, above n 5, p 3.

123 Hodkin v Registrar General of Births, Deaths and Marriages [2013] UKSC 77.

124 HJ (Iran), above n 18, at [30].

125 Application by Guardian News and Media, in HM Treasury v Ahmed [2010] UKSC 1 at [53].

126 R v Horncastle, above n 120.

127 Applications nos 26766/05 and 22228/06.

128 R v Horncastle, above n 120, at [41].

129 Michael, above n 121.

130 Bailey and Another v Angove's PTY Ltd [2016] UKSC 47 at [27].

131 Montgomery, above n 122.

132 Rogers v Whitaker (1992) 175 CLR 479.

133 Glenn, HPPersuasive authority’ (1987) 32(2) McGill LJ 261 at 264.

134 Hodkin, above n 123.

135 R v Registrar General, ex p Segerdal [1970] 2 QB 697 (CA).

136 Hodkin, above n 123, at [36].

137 Ibid, at [37]–[39].

138 Ibid, at [53]: ‘The point which I seek to illustrate is that it is not appropriate that the Registrar General or courts should become drawn into such territory [ideas about the nature of God] for the purpose of deciding whether premises qualify as a place of meeting for religious worship’.

139 Segerdal, above n 135.

140 (1983) 154 CLR 120.

141 Hodkin, above n 123, at [57].

142 Hodkin, above n 123, at [60].

143 A v Secretary of State for the Home Department [2004] UKHL 56, [2005] 2 AC 68.

144 Reed, above n 1, at 265.

145 Michael, above n 121, at [84].

146 Nicklinson, above n 90, at [224].

147 Thus, the UKSC clearly avoids what Goldsworthy, above n 91, p 118 refers to as ‘pseudo-interpretation’.

148 Hirschl, above n 2, p 42.

149 Reed, above n 1, at 265.

I would like to thank Richard Rawlings, Cheryl Saunders, Alison Young and the journal’s anonymous reviewers for their very helpful comments on an earlier version of this paper.


Judicial constitutional comparativism at the UK Supreme Court

  • Christina Lienen (a1)


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