This article addresses the unresolved question as to whether estoppel by convention can arise from a precontractual understanding. Answering that question requires consideration not only of issues of fairness in contractual dealings and the need to protect the integrity of written contracts, but also the nature and history of estoppel by convention, the relationship between the common law and equity, and the need for consistency between analogous doctrines. I argue in this article that considerations of authority, justice and policy favour allowing estoppel by convention to arise from a precontractual understanding. An examination of the cases reveals an overlooked history: some of the foundational cases of estoppel by convention involved precontractual understandings. The difficult question is not whether estoppel by convention can arise from a precontractual understanding, but whether it can contradict a subsequent written agreement. Considerations of justice, including the need for consistency between analogous doctrines, favour allowing it to do so, while policy considerations do not provide a compelling case to the contrary.

Taxonomic uncertainty has long been a feature of equitable estoppel. While the unifiers had their heyday in a period roughly centred on the 1980s, the splitters are now in the ascendant. At the forefront of the movement is Ben McFarlane, who has argued that what is known as ‘equitable estoppel’ in fact consists of five separate principles. This paper questions that growing consensus. It considers the case for the unity of equitable estoppel by identifying what might be understood to be its core principle, and then considering a series of questions that can help us to understand whether that core principle can be said to underlie ‘equitable estoppel’ as a whole. A central plank in the case for the disunity of equitable estoppel is the claim that a promise is required for some categories of case but not others. While there is some strength in the argument that a promise should be required, numerous leading cases arising in different contexts make it clear that responsibility for detrimental reliance on an assumption as to one’s future conduct does not depend on the making of a promise or commitment.

Abstract It is now well recognised that contractual purposes play an important role in the construction of contracts. The methods by which purposes are taken into account have not, however, been systematically explored. This paper considers three central issues in the purposive construction of contracts: first, the reasons contractual purposes are relevant to the interpretation of express terms and the identification of implied terms; secondly, the way in which contractual purposes are identified and distinguished from individual party interests; and, thirdly, the different ways in which contractual purposes inform the processes of interpretation and implication. It is argued that reference to contractual purposes can both raise and resolve interpretive choices, and that purposive construction plays a significant and under-recognised role in the identification of implied terms.

, Form and Substance in Anglo-American Law: A Comparative Study of Legal Reasoning, Legal Th eory, and Legal Institutions ( Oxford , Clarendon Press , 1987 ) . 2 D Kennedy , ‘ Form and Substance in Private Law Adjudication ’ ( 1976 ) 89 Harvard Law Review 1685 . 3 K Barker, ‘ Form and Substance: Th ree Observations on the State of Debate ’, this volume, ch 18 , text accompanying nn 5 – 9, identifi es no fewer than 13 diff erent kinds of distinction between form and substance. 1

Equitable estoppel gives rise to a distinctive and controversial form of liability, which arises where one person (the inducing party) leads another (the relying party) to believe that the inducing party will act in a particular way in the future, and the relying party acts on that assumption to his or her detriment. Liability of this kind has a respectably long history in English law, but has cycled through a number of expansionary and contractionary movements. This paper explores the basis of this category of liability, sketches its cyclical movements, and advances an explanation as to why views differ so sharply as to whether it should exist. The principle appears to occupy an uneasy and insecure place on the edge of the law of obligations, suggesting that it lies at the limits of what people are, as a matter of legal obligation, entitled to expect from one another.

The development of the law of obligations across the common law world has been, and continues to be, a complicated story of unity, divergence and convergence. The common law jurisdictions of the United States broke away early and developed their own distinctive version of the common law. In major Commonwealth jurisdictions the common law of obligations for some time remained relatively uniform as a result of a number of different forces, some more formal and direct than others. The law of contract, tort, equity and restitution in these jurisdictions was held together: first, by the view that the common law remained essentially a single body of law; secondly, by the Privy Council acting as the ultimate appellate court for many jurisdictions; thirdly, by courts outside England treating decisions of the House of Lords as binding and, later, with deference. While those formal ties have loosened their grip over time, other less formal factors continue to play a unifying role.The story of unity, divergence and convergence in the common law, as well as the theoretical underpinnings of that story, are addressed in the essays in this book, particularly in the context of the common law of obligations.

1. Unity, Divergence and Convergence in the Common Law of Obligations Andrew Robertson and Michael Tilbury 2. The Influence of Comparative Law on the English Law of Obligations Andrew Burrows 3. Unity,Then Divergence: The Privy Council, the Common Law of England and the Common Laws of Canada, Australia and New Zealand Paul Finn 4. A Conscious Effort to Develop a 'Different' Common Law of Obligations: A Possible Endeavour? Goh Yihan 5. A Common Law of Tort: Is there a European Rift in the Common Law Family? Paula Giliker 6. A Judicial Perspective on the Development of Common Law Doctrine in the Light of Statute Law Anthony Mason 7. Public Actors and Private Obligations: A Judicial Perspective Sian Elias 8. The Tort Liability of Public Authorities: A Comparative Analysis Peter Cane 9. We'll Meet Again: Convergence in the Private Law Treatment of Public Bodies Niamh Connolly 10. How to have a Common Private Law: The Presuppositions of Legal Conversation Allan Beever 11. The Philosophies of the Common Law and their Implications: Common Law Divergences, Public Authority Liability and the Future of a Common Law World Dan Priel 12. Obligations, Governance and Society: Bringing the State Back In TT Arvind 13. Divergent Evolution in the Law of Torts: Jurisdictional Isolation, Jurisprudential Divergence and Explanatory Theories James Goudkamp and John Murphy 14. Common Law Values: The Role of Party Autonomy in Private Law Sarah Worthington

In the law of contract questions of risk allocation properly turn, where possible, on interpretation of the agreement. This essay will explore the limits of that approach. It will do so by considering two doctrines that lie at the boundaries of contract interpretation: the implication of terms in fact and the remoteness principle. Both doctrines have been commonly understood as exercises in gap filling, but in two influential judgments Lord Hoffmann sought to recast them as interpretative principles (Attorney General of Belize v Belize Telecom Ltd [2009] 1 WLR 1988 and Transfield Shipping Inc v Mercator Shipping Inc (‘The Achilleas’) [2009] 1 AC 61). It will be argued that the implication of terms in fact can properly be regarded as an exercise in interpretation, but the same cannot be said of the remoteness doctrine. In their embrace of an interpretative approach to remoteness and rejection of an interpretative approach to implication, the English courts have backed the wrong horse.

Oxford , Hart Publishing , 2015 ) . 2 See A Roberson and M Tilbury (eds), ‘ Unity, Divergence and Convergence in the Common Law of Obligations ’ , ibid ch 1. 3 See esp J Goudkamp and J Murphy, ‘ Divergent Evolution in the Law of Torts: Jurisdictional Isolation, Jurisprudential Divergence and Explanatory Theories ’ , ibid ch 13. 4 See Goudkamp and Murphy, ibid and Goh Y, ‘ A Conscious Effort to Develop a “ Different ” Common Law of Obligations: A Possible Endeavour ? ’ , ibid ch 4. 5 P Cane, ‘ The Tort Liability of Public Authorities ’ , ibid ch 8 and N Connolly, ‘ We ’ ll Meet Again: Convergence in the Private Law Treatment of Public Bodies ’ , ibid ch 9. 6 D Priel, ‘ The Philosophies of the Common Law and their Implications: Common Law Divergences, Public Authority Liability, and the Future of a Common Law World ’ , ibid ch 11. 1

This paper argues that proximity plays a central, unifying role in duty of care analysis. The paper begins by analyzing the nature and limits of proximity. It is argued that there is a basic flaw in the classical Donoghue v Stevenson formulation of proximity. The problem is that whether a person ought to take care to avoid harm to another in a given situation does not and cannot depend entirely on the closeness and directness of the effect of the first person’s conduct on the second. Rather, proximity is one of several factors that must be taken into account in determining whether a person in the defendant’s position ought, as a matter of interpersonal responsibility, to have had a person in the plaintiff’s position in contemplation. Proximity is, however, a centrally important factor which unifies duty of care analysis across a diverse range of fact categories, as the Australian experience has shown. Although the High Court of Australia purported to reject proximity as a duty criterion, proximity has continued to play a critically important role in decisions of that court in a wide range of cases involving bodily, psychiatric and economic harm, both public and private actors, and a variety of different kinds of relationships.

The concept of an assumption of responsibility plays a central role in liability for pure economic loss, liability for omissions and at least some non-delegable duties of care. Since its emergence or revival in Hedley Byrne & Co Ltd v Heller & Partners Ltd [1964] AC 465, a half-century of case law has yielded a wealth of fact situations and analysis, but has left unresolved fundamental questions about the assumption of responsibility as a basis of obligation. The speeches in Hedley Byrne exhibit an ambivalence about the nature of the concept which has haunted the field ever since. This paper argues that the assumption of responsibility is not a distinctive category of obligation, but simply a particular manifestation of the neighbour principle. The core idea underlying the assumption of responsibility appears to be that the defendant has engaged in some conduct in relation to the claimant, or a class of persons including the claimant, which has changed the legal relationship between the parties. The obligations arising from that conduct cannot be understood as voluntarily assumed or self-imposed. Nor can we even say that the assumption of responsibility cases are distinctive because the defendant has willingly entered into a relationship with the claimant in which it can reasonably be expected that the defendant will be mindful of the claimant’s interests. That model, too, is difficult to reconcile with the case law, and shades into a more general conception of proximity. What characterises the assumption of responsibility cases is simply that the defendant has accepted a role, or embarked on a task, in which the claimant is so closely and directly affected by the defendant’s acts and omissions that the defendant ought to have the claimant in contemplation when considering whether and how to act.

The decision in Waltons Stores (Interstate) Ltd v Maher has been widely celebrated for liberalising the doctrine of promissory estoppel in Australian law. There has, however, been considerable disagreement as to the nature and extent of that liberalisation and, on its 25th anniversary, opinions as to the effect of the decision are more sharply divided than ever. This article analyses the three different models of promissory estoppel which have been articulated and applied in Australian law since Waltons Stores v Maher: the restraint on rights model (in which promissory estoppel can operate only as a restraint on a legal right), the legal relationship model (in which promissory estoppel can arise from a promise to enter into a particular legal relationship) and the independent source of rights model (in which promissory estoppel operates as an independent source of rights, and can arise from a promise that the promisor will behave in a particular way). All three models find both support and opposition in the post-Waltons case law. It will be argued that, as a matter of consistency and justice, the independent source of rights model is to be preferred. There are no compelling reasons of justice or policy to confine the doctrine in the manner required by the restraint on rights model or the legal relationship model.

This article offers an understanding of the law of negligence which explains its concern with both interpersonal justice and community welfare. It argues that close attention to the structure of the duty of care inquiry and the reasoning in duty cases suggests that the law of negligence has an underlying community welfare purpose, but that purpose is not to be found in notions of deterrence, compensation or the improvement of standards of behaviour. The community welfare purpose underlying the law of negligence must be one that is more directly served by doing interpersonal justice. The best available explanation is that the law of negligence functions to maintain civil peace by providing an avenue of recourse for certain interpersonal wrongs. This analysis explains why the duty inquiry focuses primarily on considerations of interpersonal justice but, like other private law doctrines, also attends to the community welfare effects of imposing liability.

This paper seeks to develop a deeper understanding of the role of policy-based reasoning in the determination of duty of care questions. In order to do this, the first part explores the distinction between considerations of interpersonal justice and considerations of community welfare in the determination of duty questions. While imperfect, the distinction illuminates the nature of the factors taken into account by courts in determining duty of care questions and has practical as well as theoretical implications. The second part of the paper analyses the respective roles of interpersonal justice considerations and community welfare considerations in a sample of first instance and intermediate appellate cases from England and Canada. That study suggests that community welfare considerations play a far less significant role in determining duty cases at the first instance and intermediate appellate level than at the ultimate appellate level. Analysis of the cases also reveals significant differences between the English and Canadian courts in their approaches to the interpersonal justice and community welfare aspects of duty of care questions.