As the requirements of formality have become tighter and more frequently unsatisfied, proprietary estoppel has taken on greater significance. Claims have become substantially more common since Fry laid down his tests although successes in pursuit of the claim are still rare. It is still considered a last resort for the courts to disregard formality as the steady basis for property dealings. As the Law Commission put it: ‘In putting forward the present recommendation (the replacement of part performance with proprietary estoppel) we rely greatly on the principle, recognised even by equity, that ‘certainty is the father of right and the mother of justice’. This report came five years after Oliver J in Taylor Fashions had criticised the ‘confines of some preconceived formula serving as a universal yardstick for every form of unconscionable behaviour’. Judge Oliver however was not relaxing the evidentiary requirements that would be sufficient for a claim to succeed, only attacking the ‘hard and fast rules’ that restricted the court’s attempts to rectify the unconscionable. He believed that an assurance, a reliance and a detriment should still form the cornerstone of any successful claim, but that the courts should avoid restricting their capacity to acknowledge unconscionable outcomes by following strict rules – an implicit criticism of Fry’s ‘probanda’.
But did the shift to the conscionability of conduct as the basis for a claim have any real effect on proprietary estoppel’s scope as an equitable remedy? In Taylor Fashions, Oliver found that the landlord’s representation to the tenant of the renewability of the lease was conscionable as although the tenant had acted to his detriment upon the knowledge, it had been his solicitor’s advice that had compelled him to act. Even though the landlord had knowingly withheld the information, the unconscionability had to arise from a combination of the landlord’s behaviour and the tenant’s reliance upon a specific assurance from him (a condition discussed later). Equitable remedies are always subject to a compromise between the certainty craved in law and a level of flexibility that allows the courts of equity to respond to the injustices they were designed to rectify. Oliver J didn’t intend a proliferation of cases or even an artificially heightened rate of success, but rather to set a more flexible and equitable method of deciding the validity of cases.
An examination of the judicial development of proprietary estoppel suggests that Gillett v Holt is merely a continuation of a 20th century trend, especially in the last 20 years, towards broadening its remit whilst giving greater emphasis to unconscionability as the basis for successful claims. In Jones v Watkins (unreported), Slade LJ's judgment contains some important observations about the possibility of proprietary estoppel arising from an equivocal representation: ‘The equivocal nature of the promises found by the judge is clearly one relevant factor when considering whether or not it would be unconscionable to permit the administrators to rely on their strict legal title’. Walker (in Gillett v Holt) cites Inwards v Baker to repudiate the argument that there must be a ‘mutual agreement’ as to the content and method by which an interest may be granted, or any sense of a bargain between the parties (see Yaxley v Gotts (2000) per Robert Walker). It is the ‘bare fact of A encouraging B to incur expenditure on A's land’ that provides the necessary link. He cites Wayling v Jones in which Balcombe LJ stated in regard to detriment and reliance at p 173 that ‘the promises relied upon do not have to be the sole inducement for the conduct: it is sufficient if they are an inducement— see Amalgamated Property Co v Texas Bank’. In Greasley v Cooke Lord Denning had asserted that if a causal link between an assurance and a detriment could be shown, reliance would be presumed. It was established in Crabb v Arun District Counci that it is not necessary that the party to be estopped should know exactly what the other party was intending to do in reliance on the belief which the party to be estopped had encouraged. In the light of these judgements, Walker J certainly couched his own as no more than the crystallisation of a judicial trend, moving away from the strictures of Fry’s ‘probanda’ towards interrelated and flexible ideas of an assurance, a reliance and a detriment as aspects of a wider enquiry into the unconscionability of enforcing legal rights.
Judge Walker assessed the first instance judge’s decision that the detriment incurred by Mr Gillett in living and working on the farm for over 30 years was not sufficient to give rise to proprietary estoppel. Walker responds by dismissing the idea of the three elements as ‘watertight compartments’ that must be established independently and that the ‘quality of the relevant assurances may influence the issue of reliance, that reliance and detriment are often intertwined, and that whether there is a distinct need for a "mutual understanding" may depend on how the other elements are formulated and understood. Moreover the fundamental principle that equity is concerned to prevent unconscionable conduct permeates all the elements of the doctrine’ It is the relationship between the assurances made and the detrimental reliance that is crucial in determining whether the outcome is unconscionable, and this requires a broad approach like the one outlined by Oliver J in Taylor Fashions. He criticised the use of Taylor v Dickens (which by this point had been discredited) as justification for making the irrevocability of promises a special condition upon which proprietary estoppel could be founded. Walker reasoned that it was irrelevant that Gillett was aware that the promises might be revoked, as it was the extensive reliance upon them to his detriment that would allow the courts to find them irrevocable. Judge Weeks in Taylor v Dickens had rather missed the point of the doctrine: to find the irrevocability of promises that had not been established formally in the behaviour of the parties.
Nevertheless, there have been efforts within more recent case-law to maintain boundaries of eligibility within the rather nebulous concept of unconscionability. Walker cites Balcombe LJ again : “There must be a sufficient link between the promises relied upon and the conduct which constitutes the detriment—see Eves v Eves; the issue of detriment must be judged at the moment when the person who has given the assurance seeks to go back on it; and the detriment alleged must be pleaded and proved”. Lloyd v Dugdale (2001) established that the detriment must be personal and cannot be derived to another person or entity (in this case a company). In Re Basham (1986) the tripartite requirement was endorsed when it was shown that even with an implication of reliance and great detriment, the action would fail without a specific assurance. Ultimately, the success of a claim will rely on whether it is a ‘just outcome’ (see Sledmore v Dalby (1996) per Hobhouse LJ)
For decades, Fry’s ‘probanda’, which restricted proprietary estoppel’s ambit to landowners behaving fraudulently and actively encouraging detrimental reliance, were applied beyond the ‘unilateral mistakes’ that were clearly their only scope. Judges had limited discretion when faced with cases where both parties were unaware of the legal position (bilateral mistakes) or where the estoppel arose from common expectation of a legal arrangement between the parties (where the parties had a longstanding acquaintance). Taylor Fashions finally put paid to this inequitable restraint upon the courts by subjugating the various evidentiary hurdles and qualifying provisions to the overriding concern of rectifying the unconscionable. It is that judgment that has been described as "a watershed in the development of proprietary estoppel" in Gray’s Elements of Land Law. With this in mind, Gillett v Holt’s influence alone should not be overstated, but rather it is Judge Walker’s succinct and elegant appraisal of the present position of the doctrine that is most memorable about the case, coupled of course with its superior status as a Court of Appeal case.
The final issue to be addressed is whether looking ‘at the cases in the round’ will result in more successful claims. What must first be acknowledged is that estoppel remains a drastic course of action for a court to allow and the natural restraints of judicial conservatism ensure that the formality of property law will always be paramount. The emphasis upon unconscionability has allowed the courts to conduct a broader examination of the facts without being restrained by the necessary satisfaction of inflexible criteria. Clearly the subjugation of the three criteria to the determination of unconscionability which one can only really infer from them presents a logical difficulty. They are however necessary without being sufficient, and the fluidity of unconscionability as a term allows case by case judgements with a broad discretion. Yet the broadness of the examination by no means implies that the standards of evidence required by the courts have dropped, only that more types of evidence might have relevance. Clearly to reduce the evidentiary standard in regard to the quality required to establish facts would invite more claims and with less to prove, more successful claims. Neither Oliver J in Taylor Fashions nor Walker J in Gillett v Holt give any rise to believe that the bar has been dropped in this regard. All that has been done is to mirror the myriad informal arrangements that may give rise to proprietary estoppel with an appropriately flexible approach; to find a balance between the need for certainty that even equity acknowledges and the discretion that it clearly demands.
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