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The Varieties of Restitution

The Varieties of Restitution

2nd edition

By Ian Jackman


Over the past decade, the High Court has repeatedly rejected the notion that there is a unifying principle of unjust enrichment at the plaintiff’s expense, in contrast to the position in the UK. This book provides a vigorous and sustained justification for the Australian position, and demonstrates that the law in the UK has generated more fictions than it was ever thought to abolish. The law of restitution is shown to comprise several fundamentally distinct legal concepts which fill gaps in the law of contract and tort, and which have nothing in common beyond the historical accident that they arose out of the action of indebitatus assumpsit. These are (i) the recovery of non-voluntary payments (by mistake, duress, undue influence, unconscionable dealing and total failure of consideration); (ii) remuneration for goods or services requested by the defendant in circumstances indicating a promise to pay for them; and (iii) the protection of certain facilitative institutions of private law (such as private property and fiduciary relationships). The book staunchly defends the traditional common law approach of analysing legal principles by the empirical method of treating like cases alike, rather than by derivation from supposedly unifying theories. This edition updates the first edition, which was published in 1998, in the light of almost 20 years of case-law and academic debate. It also adds a separate chapter dealing with the history of the law of restitution and why it matters.


Table of Cases
Table of Statutes

1.    Introduction

2.   The History of Restitution and Why It Matters

3.   Mistaken Payments

4.   Duress, Undue Influence and Unconscionable Dealing

5.   Payments Made on a Total Failure of Consideration

6.   Voluntary Provision of Benefits in Kind

7.   Non-Voluntary Provision of Benefits in Kind

8.   Restitution for Wrongs

9.   Proprietary Claims and Proprietary Remedies

10. Defences



This updated edition of a book first published in 1998 is scholarly, powerfully argued and laudably concise. When released it attracted comment and critique from leading private law academics including Professors Peter Birks and Michael Bryan. This was surely indicative of the book’s erudite contribution to the study of restitution law, as well as the contentious nature of Jackman’s argument, which rejects the notion that the law of restitution is explained by a single unifying principle, namely “unjust enrichment at the plaintiff’s expense”.
         Jackman’s view is that the three broad categories addressed by restitution law – the reversal of non-voluntary transactions; the fulfilment of non-contractual promises; and restitution for wrongs (protecting facilitative institutions of private law) – are distinct concepts not capable of explanation by a single principle. Readers may not agree, but will benefit from Jackman’s careful exposition of his argument.
         In a new chapter added to this edition, Jackman identifies three outcomes arising from “the tendency to ignore legal history in this field”: first, that unjust enrichment theory has produced an undesirable number of legal fictions; second, the pursuit of a unifying theory “cuts against the historical grain of the common law method”; and finally, attempts to reframe and replace legal principles developed over centuries (each based on different concepts of justice) should be avoided.
         This is a fascinating read.

Alistair Haskett, InPrint, Law Institute Journal Victoria, September 2017

Restitution scholars could be forgiven for thinking that Ian Jackman SC, long a staunch opponent of ‘unjust enrichment’ theory, has chosen his moment rather well. Nineteen years separate this book from its first edition, and a prominent advocate of unjust enrichment theory, Justice James Edelman, has recently taken his seat on the Bench of the High Court of Australia.
         English scholars and jurists have in recent decades sought to unite aspects of the law of restitution under the umbrella of ‘unjust enrichment at the plaintiff’s expense’. The author makes clear that his intent is to defend the heterogeneous conception of restitution that persists in Australian law. This defence is achieved by a thoughtful and detailed examination of the diverse components and origins of restitution law.
         Jackman delves as far as back as mediaeval law to trace the development of restitution through the indebitatus counts. From there, he outlines his view of three broad categories of restitution: non-voluntary conferral of an incontrovertible benefit (chiefly for mistake, duress, or total failure of consideration); benefits voluntarily conferred; and restitution for wrongs. With the use of both historical and very recent examples, the author demonstrates how restitution law has grown alongside and between other areas of the law.
         This book will give the most pleasure to scholars of restitution. However, the book’s greatest virtue is its subtle but effective exposition of the operation (some might say vagaries) of the common law. Restitution simultaneously operates between and above contract, property, equity, and tort, providing justice where these areas of law do not. As such, it has inevitably developed as a set of disparate legal principles and actions.
         Mr Jackman’s well-articulated and compelling assessment is that this is not a flaw in need of remedy, but a sign of restitution’s practical utility as a branch of the common law. By the end of this book, most readers will be inclined to agree with him.

Phillip Thomas, Ethos, ACT Law Society, June 2017

This is the second edition of a work which was first published in 1998 to wide acclaim for its illuminating and penetrating discussion concerning the taxonomical possibilities of that area of law which is sometimes referred to as “restitution”. The initial edition added substantially to the identification of the structure of this area of the law in its various incantations. This second edition modernises the discussion by taking into account the ever widening divergence between English and Australian law and the vigorous eschewing by the High Court of any unifying or underlying principle. …
         It matters not on which side of the debate one positions themselves in relation to this book. It is, without doubt, an excellent contribution to the process of understanding the diffuse structure of the law in this area. It directly confronts the arguments advanced for the “unifying principle” approach and posits a strong, but measured, defence of the existing Australian position. It explains and analyses a difficult and abstruse area of the law and, in the process, assays the modern cases in an intelligible and comprehensive way. Read full review...

Queensland Law Reporter 31 March 2017 [2017] 12 QLR


Published 17 March 2017
Publisher The Federation Press
ISBN 9781760021320
Australian RRP $150.00
International Price $136.37
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