Unjust Enrichment — Lipkin Gorman v Karpnale Ltd

At first instance and in the Court of Appeal the claim met with limited success, but the matter was ultimately appealed to the House of Lords, which delivered its landmark judgment in 1991. The case thus presented the House with a direct opportunity to address, at the highest judicial level, the doctrinal status of unjust enrichment as an independent cause of action in English private law.

The primary issue before the House of Lords was whether unjust enrichment constitutes a recognised and independent cause of action in English law capable of grounding a personal restitutionary claim, and, if so, what the necessary elements of that cause of action are. This required the House to consider whether English law had, historically or by contemporary development, accepted a unifying principle of unjust enrichment analogous to that long recognised in other common law jurisdictions, notably the United States and Canada.

The second issue concerned the defences available to a recipient of stolen money who had received those funds in good faith and without notice of the theft. In particular, the House was required to consider whether English law recognised a general defence of change of position available to an innocent recipient who had, in reliance on the receipt, acted to his or her detriment in a way that made full restitution inequitable.

A further subsidiary issue concerned the proper measure of the club's liability. Even if the claim succeeded in principle, it was necessary to determine whether the amount recoverable should be the gross sum paid to the club by Cass, or the net sum after deducting the winnings that Cass had received and returned to the firm's account — and, relatedly, whether the gaming legislation affected the enforceability of the underlying transactions.

Lord Goff of Chieveley, with whom the other Law Lords agreed on the principal points, delivered the leading speech. He began by affirming that English law does recognise a law of restitution, and that the underlying principle of that law is the principle of unjust enrichment. In so doing, Lord Goff placed the authority of the House of Lords behind the academic framework that had been most influentially articulated by Professor Peter Birks and had found earlier judicial expression in Goff and Jones's treatise The Law of Restitution. This represented a decisive break from the older classification of quasi-contractual remedies as derived merely from an implied contract, an approach that had obscured the true doctrinal basis of these claims for generations.

Lord Goff traced the historical lineage of the unjust enrichment principle to the celebrated judgment of Lord Mansfield in Moses v Macferlan (1760) 2 Burr 1005, in which Lord Mansfield had explained that the gist of the action for money had and received was that the defendant, upon the circumstances of the case, was obliged by the ties of natural justice and equity to refund the money. Lord Goff acknowledged that Lord Mansfield's broad approach had subsequently been restricted by a series of nineteenth-century decisions that sought to confine the action within artificial quasi-contractual categories, but he held that those restrictions had never truly extinguished the underlying principle, which now found its proper modern expression in the concept of unjust enrichment.

Lord Goff articulated the structure of the unjust enrichment cause of action by reference to four inquiries that a court must address: first, whether the defendant has been enriched; second, whether that enrichment was at the expense of the claimant; third, whether it would be unjust for the defendant to retain the enrichment; and fourth, whether any defences are available to the defendant. This four-stage framework, derived from the academic literature and from comparative common law sources, has since become the canonical statement of the elements of unjust enrichment in English law, and is routinely applied by the courts in subsequent restitutionary cases.

On the first element, the enrichment of the defendant, Lord Goff held that Karpnale Ltd had plainly been enriched by the receipt of the stolen money. The club received actual money, which is the paradigm form of enrichment, and there was no question that the value of what was received was measurable. The fact that the enrichment took the form of cash paid over in exchange for gambling chips did not alter this analysis: the chips were purchased with the misappropriated funds, and the club ultimately received the net proceeds of all the gambling transactions undertaken with those chips.

On the second element, enrichment at the expense of the claimant, Lord Goff confirmed that the requisite connection between the claimant's loss and the defendant's gain was established on the facts. The money received by the club had been taken without authority from Lipkin Gorman's client account. Even though the money had passed through the hands of Cass, the firm retained a legal property right in the money at the moment of misappropriation, and it was that property right which was defeated by the payment to the club. The enrichment of the club therefore came directly at the expense of the firm.

On the third element, the unjust factor, Lord Goff held that the circumstances made it unjust for the club to retain the enrichment because the money had been stolen. Theft, or more broadly the vitiation of the claimant's consent through the criminal wrongdoing of a third party, constitutes a recognised unjust factor in English law. The club had no better title to the money than Cass had had, and Cass had no title at all: he was a thief. The fact that the club was innocent and had acted in good faith was relevant not to the existence of the claim but to the availability of defences.

The most significant and enduring aspect of Lord Goff's reasoning concerned the fourth element: the availability of defences. Lord Goff expressly recognised, for the first time at the level of the House of Lords, that English law does recognise a general defence of change of position available to a defendant who has, in good faith, changed his or her position in reliance on the receipt of the enrichment, such that it would be inequitable to require full restitution. Lord Goff deliberately framed this defence in broad terms, declining to confine it within the technical limits of proprietary estoppel or estoppel by representation, which had previously been the only established doctrinal routes by which a defendant could resist a restitutionary claim on the basis of reliance.

Lord Goff made clear that the change of position defence is not available to a defendant who has acted in bad faith, and is not available to a wrongdoer. Its rationale is the protection of innocent recipients who, having received an enrichment without any wrongdoing on their part, have thereafter acted in a way that renders full restitution unjust. The defence operates by reducing the amount of the restitutionary award to the extent of the change of position, rather than by providing a complete defence in all cases.

Applying the change of position defence to the facts, Lord Goff held that the club had changed its position to the extent that it had paid out winnings to Cass. When the club provided chips to Cass and Cass won, the club paid out those winnings. Those payments represented a change of position by the club in reliance on its receipt of the misappropriated funds, because had the club not received the money it would not have entered into the gambling transactions at all and would not have made those payouts. To that extent, requiring the club to make full restitution of all sums received would be inequitable.

The House of Lords also addressed the relevance of the gaming legislation. Gambling contracts were at the time void and unenforceable under the Gaming Acts, which meant that the club could not have sued Cass to recover gambling debts. However, Lord Goff held that this did not assist the club in resisting the restitutionary claim brought by the firm. The firm's claim did not depend on enforcing the gambling contracts; it rested on the independent principle of unjust enrichment. The unenforceability of the underlying gambling transactions was therefore not a complete answer to the firm's claim.

In a significant passage delivered by way of obiter dictum, Lord Goff observed that the recognition of the change of position defence as a general principle represented the culmination of a long process of judicial development, and that the defence should be developed incrementally and with reference to its underlying rationale. He acknowledged that the precise boundaries of the defence remained to be worked out in future cases, but he was clear that the defence was now firmly part of English law and would in due course displace the piecemeal and unsatisfactory approaches that had previously been employed to achieve broadly similar results through the mechanism of estoppel.

The House of Lords held that Lipkin Gorman's claim in unjust enrichment against Karpnale Ltd succeeded in principle. Unjust enrichment was confirmed as a recognised and independent cause of action in English law. The club had been enriched at the expense of the firm by the receipt of stolen money, and the circumstances rendered it unjust for the club to retain that enrichment.

However, the amount of the award was reduced by the application of the newly recognised change of position defence. The club was entitled to set off against its liability the winnings it had paid out to Cass in the course of the gambling transactions, representing the extent to which the club had changed its position in good faith in reliance on the receipt of the money. The firm was therefore entitled to recover only the net sum by which the club had been enriched after accounting for those payouts.

The House also confirmed, in accordance with the reasoning set out above, that the change of position defence is a general defence of English law, not limited to estoppel situations, and that it is available only to defendants who have acted in good faith. On the facts of the case, there was no suggestion that the club had acted otherwise than in good faith throughout, and the defence was accordingly applied in its favour to the extent of the winnings paid out.

Lipkin Gorman v Karpnale Ltd [1991] 2 AC 548 stands as the foundational authority for the recognition of unjust enrichment as an independent cause of action in English private law. Before this decision, the courts had proceeded by analogy with contract, using the fiction of an implied contract to justify restitutionary remedies without articulating a coherent doctrinal basis. Lord Goff's speech dismantled that fiction and replaced it with an explicitly principled framework, bringing English law into alignment with the broader common law world and with the long-standing position of academic commentators. The decision is accordingly treated as the starting point for all subsequent discussion of unjust enrichment doctrine.

The four-stage analytical framework articulated by Lord Goff has been consistently applied and refined in subsequent decisions. In Banque Financière de la Cité v Parc (Battersea) Ltd [1999] 1 AC 221 the House of Lords confirmed and elaborated the framework, and it was further developed in Menelaou v Bank of Cyprus UK Ltd [2015] UKSC 66. The Supreme Court's landmark decision in Kleinwort Benson Ltd v Lincoln City Council [1999] 2 AC 349 extended restitutionary recovery to cases of mistake of law, building directly on the principled foundations laid in Lipkin Gorman.