In Henry and Mitchell v Henry  UKPC 3, the Privy Council have given further consideration to the doctrine of proprietary estoppel. The judgment of the PC was delivered by Sir Jonathan Parker and it will be of particular interest as it demonstrates the continuing importance of the Court of Appeal’s excellent judgment in Gillett v Holt  EWCA Civ 66 as well as raising (without deciding) the interesting issue of the remedy when section 116, LRA 2002 is in issue in relation to third party buyers after the estoppel has been established.
In summary, the facts are that Geraldine Pierre, who people referred to on St Lucia simply as “Mama”, allowed Calixtus Henry’s grandmother to build a house on her land and live there. Calixtus was born there and continues to live there to this day. Mama visited Calixtus’ plot daily and treated him like a son. Mama was regarded as such because of her refusal to leave St Lucia and for her willingness to let people live on her land in exchange for working on it. Calixtus was the only man up to the task. His evidence was that “Mama stated many times to me … that she would leave the land for those that worked the land and for those that cared for her in her home country”. Mama also promised him that because he lived on the land, cultivated it, and cared for her, that he would be given her share of the land on her death. The plot provided food for Calixtus and his family, as well as Mama; that he took food to her and sold any leftovers. Mama left her share in her will to Theresa Henry.
At first instance, the judge found that Mama had made a clear representation to Calixtus but that Calixtus had not acted to his detriment because he had lived on it rent free for decades, it had been his source of livelihood, and he had reaped its benefits. Further, his interest could not bind the subsequent purchaser of the land. The Court of Appeal found that Calixtus had acted to his detriment and awarded him effectively Mama’s share of the property, his “expectation interest”.
In the Privy Council, the issue was as to how the principles of proprietary estoppel should apply in this case. The question was whether Calixtus had acted to his detriment. The Board said that the process of deciding whether there had been sufficient detriment was to weigh up the advantages and disadvantages suffered by Calixtus in reliance on Mama’s promises. The process, in effect, is similar to a proportionality assessment (as to which see below). The Board followed the approach taken in Gillett that, although the criteria for establishing a claim in proprietary estoppel can be viewed individually, they are often intertwined and, in this case, that was certainly so. The Board was accordingly required to revisit the question of detriment and found that because he remained working on the land (unlike others), caring for Mama and providing food for her, and effectively depriving himself of the opportunity for a better life elsewhere Calixtus had established detriment and his equity. He had opted for a “hard life, in which he has had to struggle to make ends meet and to provide for his family, in circumstances where more attractive prospects beckoned elsewhere.
Calixtus had an overriding interest, which bound subsequent purchasers. It was argued, drawing on Gray and Gray’s excellent Elements of Land Law at para 9.2.93, that proprietary estoppel connotes an inchoate remedy which can be satisfied in a number of different ways including the payment of money depending on all the circumstances of the case. Section 116, although simple in utline, is really rather a tricky provision because although the equity arises when the detriment has been done, that does not actually affect the potential range of remedies. In relation to the equivalent provision to section 116, the Board found that it did not arise in this case because it had not been originally pleaded. However:
The Board does not rule out the possibility that cases may arise in which the particular circumstances surrounding a third party purchase may, notwithstanding the claimant’s overriding interest, require the court to reassess the extent of the claimant’s equity in the property. 
With respect to the parties in this claim, this was the most interesting and important issue of law (see my reflective piece which touches this issue in relation to section 2, LPMPA, but could have amplified further in relation to section 116) and it’s a shame that the Board were not able to address it.
Thus, the remedy was in issue. The Board stressed the following idea: “Proportionality lies at the heart of the doctrine of proprietary estoppel and permeates its every application” (at ) – a comment which should be in the heads of all practitioners and students (although I fear it won’t be in the minds of the latter).
Calixtus got one half of Mama’s share, now vested in Theresa Henry, as the minimum equity to do justice to his claim. They might have done more here to justify this outcome, but the overall feeling is that Calixtus was not best served by the St Lucian courts.