PROPRIETARY ESTOPPEL IN THE SUPREME COURT: BANQUO'S GHOST?

THE facts of Guest v Guest [2022] UKSC 27, [2022] 3 W.L.R. 911 fitted a familiar pattern. For over 30 years, Andrew worked and lived on Tump Farm, owned by his parents, David and Josephine, for low wages. David promised Andrew (taking account of other familial expectations) a sufficient share of the farm to enable him to run a viable farming business on the parents’ deaths. The parents made wills accordingly. But following a falling out, Andrew was removed from the wills and left Tump Farm. The judge’s undisturbed conclusion ([2019] EWHC 869 (Ch)) was that Andrew had made out a proprietary estoppel claim against his still-living parents: he had relied to his detriment on David’s non-contractual promises, such that it was unconscionable for David to resile from them. The case invited the Supreme Court to consider a fundamental question, effectively for the first time in living memory at the highest level: should successful estoppel claimants like Andrew generally have their expectations fulfilled, should they generally be limited to having their detriment reversed, or was the correct approach a third way? The precise answer divided the panel, which issued two lengthy judgments (lacking explicit direct engagement with each other) over 10 months after the one-day hearing. Leading the majority, Lord Briggs (with whom Ladies Rose and Arden agreed) identified the objective of an estoppel remedy as compensating for the unconscionability caused by the defendant promisor in repudiating their representations. The preferable and simplest way of remedying that unconscionability was to assume (not presume) that claimants should have their expectations fulfilled. This was to be the “starting point” in “many cases”, although “considerations of practicality, justice between the parties and fairness to third parties may call for a reduced or different award” (at [94]). Lord Briggs grounded his approach in previous case law, identifying satisfying expectations as the “main driver of the remedy” (at [22]). Following a detailed review, he concluded that “there is not a single English authority favouring the approach that the essential aim of the remedy was to protect the claimant’s reliance interest and therefore to compensate for the detriment” (at [52]). Inter alia, he emphasised that the “minimum equity”-based approach in Crabb v Arun District Council [1976] Ch. 179, 198 was not about identifying expectation and detriment and then awarding whichever was cheaper for the defendant. Rather, Scarman L.J. in Crabb was concerned with the “minimum equity to do justice” (emphasis added), with “justice” meaning remedying the unconscionability in the repudiation of the Cambridge Law Journal, 82(1), March 2023, pp. 13–16 © The Author(s), 2023. Published by Cambridge University Press on behalf of The Faculty of Law, University of Cambridge. This is an Open Access article, distributed under the terms of the Creative Commons Attribution licence (https://creativecommons.org/licenses/by/4.0/), which permits unrestricted re-use, distribution, and reproduction in any medium, provided the original work is properly cited. doi:10.1017/S0008197323000119