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MWB v Rock and the Supreme Court's Dereliction of Duty - a Misuse of Judicial Discretion?


The recent Supreme Court decision in MWB v Rock Advertising[1] has been the subject of much criticism[2] for its failure to address the issue as to what constituted valid consideration. Had such an evaluation taken place, it would have gone a considerable way towards clarifying the current law on consideration and resolving the tension between Foakes v Beer and the concept of ‘practical benefit’ in Williams v Roffey. However, Lord Sumption, delivering the judgment of the majority, paid little more than lip service to the consideration issue. His description of the issue as “difficult”,[3] and the necessity of dealing with it as “undesirable”,[4] is noteworthy, particularly considering his assertion that “any decision on this point is likely to involve a re-examination of the decision in Foakes v Beer”[5]. Despite Foakes v Beer being “ripe for re-examination”,[6] His Lordship left the task of overruling or modifying it to a future court – one, he suggests, that should include an “enlarged panel of the court”,[7] where any ruling would be more than obiter dictum.

It is submitted that the criticisms of the court are justified in the instant case. The first discussion will centre around the court’s dubious justifications for failing to give a ruling, and how they thinly disguise a misguided exercise of judicial discretion. Moreover, this essay will refute the counter arguments in favour of the MWB decision, demonstrating that the judgment does not enrich the existing body of case law on consideration and bestows little to no benefit. The second point of discussion will take a constitutional angle. It will consider the issue of judicial discretion and argue that the omission of the court in MWB is symptomatic of a wider shift towards constitutional judicial autonomy. However, it is argued that this shift is itself not a negative development, and that the weaknesses of MWB should not necessarily be conflated with judicial discretion itself.


There is no reason to take Lord Sumption’s words at anything other than face value. The argument that a substantial opinion on consideration is in fact given (i.e. that Foakes v Beer[8] is more “precarious than ever”[9]), yet for some reason kept deliberately vague, makes little sense given His Lordship’s strong words. Moreover, the justification for the court’s evasion of its duty to give a ruling is at best extremely weak – obiter dictum would still have provided some measure of clarity regarding the position and would also have provided a new basis for future courts to work from. It is also to be noted that obiter dictum has, certainly within contract law, proved a formidable force on its own merits (see e.g. Lord Denning’s obiter dictum in High Trees,[10] from which the doctrine of promissory estoppel was born). Thus, the submission that no ruling is better than non-binding obiter dictum does not withstand much scrutiny, given its utility in earlier contract law. The explanation for the court’s reluctance to rule on such an anticipated issue must thus be that it did not feel it had a duty to do so; it could simply abrogate the responsibility by ‘passing on’ the issue to a future court. This is revealed by Lord Sumption’s use of the word “undesirable”,[11] which is, notably, tacked on to the end of his assertion that it is also “unnecessary”.[12] Had the court discreetly wanted to avoid the issue, His Lordship could easily have omitted this sentence. The question for commentators would instead have been why it was unnecessary to deal with the issue, rather than why the court deemed it undesirable.

A. Counter arguments

It has been suggested[13] that the court’s decision was made to achieve certainty within the law, and that Lord Sumption’s obiter merely indicates that desire of the bench, rather than the misuse of judicial discretion. By extension, it could be argued that the outcome in MWB is therefore beneficial since the certainty provided by a future “enlarged panel”[14] would be commercially advantageous. However, the weakness of this argument is twofold. Firstly, it hinges on a purely hypothetical scenario in which the consideration issue happens to reach the Supreme Court a second time. Given the lengthy appeal process, such an occasion may be far too distant in the future to be of any benefit. The considerable expense involved in bringing an appeal is also a significant hurdle and would perhaps deter future litigants from pursuing a similar claim further. A good illustration of an issue which has yet to be clarified by a hypothetical future court is that of common mistake – fifteen years after Great Peace[15], the law in this area still leaves a great deal to be desired in terms of clarification. Moreover, this is essentially a straw-man argument, as it proposes that the benefit derives from the said hypothetical scenario and not directly from the MWB decision itself. Secondly, it is fallacious to isolate the desire for certainty – which this essay does not dispute exists – from a misuse of judicial discretion. The use of discretion in omitting to give a ruling is an action which is in part instigated by the desire to give certainty, which is a motive. The philosophical differences between the two are beyond the scope of this essay, but it is material that they are distinct. Instead of viewing the situation as a binary either/or, it must be recognised that Their Lordships’ motives may have been noble, but their avoidance of their duty in the instant case is problematic.


A. Why a constitutional approach?

Given the use of judicial discretion to avoid such a pertinent issue, an analysis of the decision in MWB v Rock is thus incomplete without reference to the constitutional framework in which the court operates. That the Supreme Court is becoming more rights-based[16] in its approach, nearing the role of a constitutional court in many respects, is difficult to refute. Lord Steyn’s obiter in the landmark case of Jackson v Attorney General is infamous for its indication of a greater role for the Supreme Court: “a new Supreme Court may have to consider whether this [judicial review] is a constitutional fundamental which even a sovereign Parliament...cannot abolish.”[17] This declaration echoes C.J. Marshall’s assertion in the US case of Marbury v Madison that "It is emphatically the province and duty of the judicial department to say what the law is,"[18] although it could be said that the parallels are not quite exact due to the existence of a codified constitution in the US which is still lacking in the UK. Nevertheless, Jackson arguably goes beyond the scope of Marbury, since the US constitution is capable of amendment by the executive via a supermajority, whereas Lord Steyn appears to be acknowledging that there are certain constitutional principles which trump the executive entirely. More recently, in the case of Nicklinson, the Supreme Court held that it was within its own jurisdiction to issue a declaration of incompatibility as regards the Suicide Act 1961 and its conflict with Art. 8 of the ECtHR[19] (although, with the exception of Lady Hale, dissenting, it stated it would not do so[20] at the time). Recent case law thus suggests that the judiciary of the Supreme Court is taking a more activist approach, arguably to the extent of flirting with policy-making[21]. Far from being alienated from this trajectory, the reasoning in MWB v Rock affirms it. The judiciary have taken upon themselves the constitutional power to use discretion to protect rights (as in Jackson), or to decline to take any action at all (as in Nicklinson). The failure to provide clarity in MWB v Rock is an extension of this discretion, analogous to the decision not to issue a declaration of incompatibility in Nicklinson.

It might be argued that this is a false analogy because the changing role of the court is at least partially due to the powers conferred under s.3 and 4 of the Human Rights Act 1998.[22] The development in judicial discretion has thus developed due to human rights challenges, not due to civil law issues, such as those in MWB. There is no ‘human right’ to certainty in the law of contract. It is therefore, according to this line of argument, impossible to square the court’s omission in MWB with constitutionalism. Human rights discourse and private law discourse are not interchangeable.

However, this is to take too narrow a view of constitutionalism. It is not logical that an emboldened judiciary would consider themselves equipped to challenge the policy status quo (e.g. as regards assisted suicide[23]) but not to decline to make a private law ruling. Moreover, it assumes that the realms of private law and public law are entirely separate. D. Burchardt refers to the “phenomenon of intertwinement”[24] of “legal spaces”,[25] and Mark Tushnet argues that “private law exist[s] within a framework of public law.”[26] He furthermore emphasises the fact that comparative constitutional law has a “close connection to other disciplines and fields.”[27] The ‘wrongful birth’ cases in the law of tort (for an example see Rees v Darlington Memorial Hospital NHS Trust[28]) illustrate this phenomenon of ‘intertwinement’. The claimants in such cases bring a private law claim in tort for damages incurred as a result of caring for a child who was conceived through negligence, yet the general rule (that able-bodied parents cannot claim for the costs of bringing up a healthy child[29]) is in essence motivated by policy considerations which fall remarkably close to those vital in public law cases. The judiciary’s unwillingness to categorise a healthy child as an economic burden was not explicitly linked to the Art. 2 ECHR right to life[30], but nevertheless the desire to preserve the ‘value’ of life would not be out of place in a public law action concerning Art. 2. The more pertinent issue is therefore whether the right to a remedy for breach of contract has any general grounding in human rights law, rather than whether there is a specific ‘right’ to commercially advantageous outcomes. It is possible that the right to some remedy, whether that is damages or an injunction, could be construed to form a component of the Article 6 right to a fair trial[31], although this would depend on one’s construction of ‘fairness’ and is beyond the scope of this essay. It is therefore artificial to attempt to remove the decisions of the Supreme Court from the public law environment in which the court operates and the academic literature supports this ‘holistic’ approach. For example, in ‘The Challenges Presented by Fundamental Rights to Private Law’, Hugh Collins[32] emphasises the idea that the discretion exercised by judges to engage or not engage with a particular issue cannot be neatly confined to certain types of cases. The ‘private’ vs ‘public’ law dichotomy is therefore somewhat arbitrary.

B. Has the Supreme Court failed on a constitutional level?

It therefore must be questioned whether MWB is symptomatic of a constitutional failure on the part of the Supreme Court in its duties. Has the phenomenon of judicial activism, and its expansion since Jackson and the HRA 1998, gone too far? It is submitted that the failure to give a ruling in the MWB case is worryingly arbitrary. However, while the court’s reliance on arbitrariness is troubling, it is not a new trend within contract law. For example, in ‘Mistake in contract’,[33] Treitel draws attention to the policy distinctions in Bell v Lever Bros[34] (which concerned mistake) and Associated Japanese Bank:[35]

“While there is no direct conflict between the cases, the difference in result illustrates the conflict of policies, described at the beginning of the Associated Japanese Bank case: ‘respect for the sanctity of contract” prevailed in Bell v. Lever Bros. Ltd., but yielded in the Associated Japanese Bank case to “the need to give effect to the reasonable expectations of honest men.’”[36]

It is therefore not particularly controversial that the decisions of differently constituted courts reflect the policy preferences of different judges, and thus there is always an element of arbitrariness. Judges as human beings inevitably possess unconscious – or otherwise – policy preferences. To label a ruling a failure because it is inevitably influenced by human nature is an unrealistic stance. However, there is certainly a ‘sliding spectrum’ of arbitrariness, and the outright refusal to return even obiter dictum lies beyond the bounds of what many academics and commentators deem acceptable, as evidenced by the hostile reception[37] of MWB v Rock.

A. Should the Supreme Court be bound to give judgment?

The instant case can be distinguished, because the arbitrariness of the decisions in Bell v Lever Bros and Associated Japanese Bank nonetheless derived from a ruling that was actually made. On the other hand, the arbitrary nature of the decision regarding consideration in MWB derives from the omission of a ruling. The crucial issue is therefore whether the Supreme Court should be bound to rule on issues which it knows will arise, and will require clarification, in the course of a particular case.

It is submitted that the answer must be no. To require the court to do so would be to bind it to a particular course of action, stifling judicial innovation and forcing it to sacrifice flexibility in the interests of predictability and certainty. Moreover, there would be serious contraventions of the rule of law if such a course were adopted. In ‘The Rule of Law’, Tom Bingham warns against the excessive use of judicial discretion: “The job of judges is to apply the law, not to indulge their personal preferences.”[38] However, Bingham acknowledges that “[t]here are areas in which [judges] are required to exercise a discretion...”[39] This neo-Diceyean[40] approach, in which moderation is the key, is the one most compatible with the current constitutional arrangement of the courts. The enactment of the HRA 1998, the ECA 1972 and the Constitutional Reform Act 2005 have already initiated a shift towards a US-style constitutional role for the judiciary (however, it remains to be seen whether the orthodox conception[41] of parliamentary sovereignty will acquiesce to the changing structure of the separation of powers). That this shift has already taken place is evidenced by the fact that the UK Supreme Court is beginning to acquire the comparative confidence of the US judiciary in making policy arguments. The US Supreme Court’s reversal of the Colorado Civil Rights Commission’s finding that a baker had discriminated against a gay couple by refusing to bake a wedding cake[42] is evidence of the former’s ease in handling questions of policy. To require the Supreme Court to deliver a ruling would, presumably, involve an Act of Parliament, which would be a direct intrusion by the legislative branch on the autonomy and independence of the courts. Given Lord Steyn’s formidable obiter in Jackson,[43] it is disputable whether the authority of such and Act would even be accepted by the courts. Such a ‘solution’ would undoubtedly result in greater certainty and benefit the world of commerce - but at the cost of the flexibility of the ever-developing common law. Detractors must therefore be careful in asserting that the court has ‘failed’ in its duties on a constitutional level, since this is to ignore the court’s responsibilities to exercise discretion where it sees fit.


This analysis has attempted to converge the realms of contract law and constitutional law in order to explain the behaviour of the Supreme Court in the MWB v Rock case. It is an easier alliance than the counter arguments would acknowledge. Moreover, analysing the case from twin perspectives has directed this essay to the conclusion that, while the outcome is unsatisfactory from a contract angle, it is also a sign of judicial dynamism; it is only by considering the recent constitutional developments of the judiciary that the court’s behaviour can be fully understood. It is submitted that Lord Sumption’s justification for failing to clarify the rules on consideration were, in this case, inadequate at best. The law of contract would have benefitted greatly from the obiter dictum that His Lordship refused to provide. As Lord Sumption himself implies[44], there remains a fundamental discord between Foakes v Beer and Williams v Roffey.[45] However, caution must be exercised in criticising the court’s use of discretion. One unpopular decision does not suggest that judicial discretion itself ought to be hampered, and moreover, measuring judicial decisions against popular norms is itself problematic.

[1]MWB v Rock [2018] UKSC 24 [2]See A. Arzandeh, H. McVea. ‘Refining Consideration: RIP Foakes v Beer?’ (2017) Lloyd's Maritime and Commercial Law Quarterly. 2017 Feb 1;2017(1):7-12. [3]MWB v Rock [2018] UKSC 24 (Lord Sumption at [18]) [4]Ibid.

[5]n.3 [6]n.3 [7]n.3 [8]Foakes v Beer (1884) 9 App. Cas. 605 [9]Zachary Bourne, ‘Up the Doctrine of Consideration – Reforming the Rule in Pinnel’s Case’ (2018) BLR

< Consideration-–-Reforming-the-rule-in-Pinnel’s-Case> accessed 11 July 2018

[10]Central London Property Trust Ltd v High Trees House Ltd [1947] K.B. 130 [11]n.3 [12]n.3 [13]See Elizabeth Thompson, ‘Supreme Court favours certainty over flexibility (and honour?)’ (2018) F. & C. L. [14]n.3 [15] Great Peace Shipping Ltd v Tsavliris Salvage (International) Ltd) [2002] EWCA Civ 1407 [16]See R v Secretary of State for the Home Department, ex parte Simms [2000] 2 AC 115, per Lord Hoffmann at [131] [17]Jackson and others v Attorney General [2005] UKHL 56 [102] (Lord Steyn) [18]Marbury v Madison [1803] 5 US 137, [p.178] (C.J. Marshall) [19]R (Nicklinson) v Ministry of Justice [2014] UKSC 38 [20]Ibid. Lord Neuberger at [113] [21]See e.g. R (Nicklinson) v Ministry of Justice [2014] UKSC 38, Lady Hale at [311] [22]Human Rights Act 1998, s.3, s.4 [23]n.19 [24]Dana Burchardt, ‘Intertwinement of legal spaces in the transnational legal sphere’ (2017) L.J.I.L 305 [25]Ibid. [26]Mark Tushnet, Advanced Introduction to Comparative Constitutional Law (2nd edn, Edward Elgar Publishing Ltd 2018) 2 [27]Ibid, p4 [28] Rees v Darlington Memorial Hospital NHS Trust - [2004] 4 LRC 102 [29] Ibid. [30] European Convention on Human Rights, Art. 2 [31] European Convention on Human Rights, Art. 6 [32] Hugh Collins, “The Challenges Presented by Fundamental Rights to Private Law”. In: Barker K et al. (eds.), Private Law in the 21st Century (2017) [33]G.H. Treitel, ‘Mistake in contract’ [1988] L.Q.R. 104(Oct), 501-507 [34]Bell v Lever Bros [1932] A.C. 161 [35]Associated Japanese Bank [1989] 1 WLR 255 [36]n.33 [37]n.13 [38]Tom Bingham, The Rule of Law (Penguin Books 2011) 51 [39]Ibid. [40]See A.V. Dicey, Introduction to the Study of the Law of the Constitution (first published 1885, Liberty Fund Inc. 1982) [41]n.33 [42] Masterpiece Cakeshop v. Colorado Civil Rights Commission, 584 U.S. (2018) [43]n.16 [44]n.1 [45]Williams v Rof ey Bros & Nicholls (Contractors) Ltd [1991] 1 Q.B. 1

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