Confiance légitime

Life is filled with disappointed expectations. In the maelstrom of human interactions, we make all sorts of assumptions about the state of affairs, the ways in which others will behave, the recurrence of stable practices, the veracity of what appears to be real. We adjust our own behaviour on the basis of these assumptions. Often these assumptions prove to be wrong, and relying on them turns out to be detrimental. Does the law care? Should it care? As a legal idea, detrimental reliance sits uneasily between two destinies. In one story, it becomes the foundational principle for all of the law of obligations, explaining and justifying the enforcement of contracts and the reparation of wrongful harm. In the opposing story, it disintegrates—and disappears—into a multiplicity of discrete legal doctrines, each with its own peculiar conditions and effects. Neither story is compelling. Detrimental reliance is at its normative best when it can be imagined as a distinct and cohesive set of private law rules giving effect to a basic intuition: reasonable assumptions can be relied upon and should produce effects in law, under the right circumstances. But this intuition is not sufficiently precise to be operational. More needs to be said to avoid the perils of equivocation. Beginning with Lon Fuller’s socio-legal idea of “stable interactional expectancies,” there are a number of well-known efforts to establish detrimental reliance as a general principle, if not the foundational principle of the law of obligations itself. Xavier Dieux in Belgium, citing Jean Carbonnier in France, himself citing Gino Gorla in Italy, stated that the legal (and moral) basis of contractual obligation is not the promise of the debtor, but the reasonable reliance of the creditor, who puts his faith in the words of the promisor, changes his position, and thereby exposes himself to loss when the promise fails. Yet one cannot escape the sense that these authors were looking at two sides of the same coin. In the context of reciprocal agreements, promise and reliance are not severable. Similarly, in the Anglo-American world, the battle raged for a couple of decades at the end of the twentieth century, between the contract-as-promise believers and their contract-as-reliance detractors. But of course, reliance and promise never fully merge as the basis for contractual obligation. In all jurisdictions, a contractual promise is valid and enforceable as such, whether or not it has been relied upon. Conversely, not all instances of reliance yield contractual remedies. Not much seems to be gained by forcing the law of contracts into the reliance mould. The same can be said with parallel efforts to explain the entire law of wrongful harm through detrimental reliance. While it is true, in a sense, that all wrongdoing (intentional or negligent) is behaviour that violates the reasonable assumption of social actors that others will respect their significant interests, there is no analytical traction drawn from that statement. Reliance here is notional, much like consent is notional in the concept of the social contract. The idea of private law as protection of legitimate, detrimental reliance at once explains everything, and nothing. On the other hand, both common law and civil law are replete with examples of private law obligations and legal outcomes flowing from the moral intuition that reasonable assumptions deserve protection. Traditional and more recent doctrines in the common law tradition, loosely gathered under the old label of “estoppel” and often connected to equity, provide variable remedies to the person who relies to his detriment on mistaken assumptions induced by the non-wrongful conduct or words (short of binding promise) of others. Proprietary estoppel, promissory estoppel, equitable estoppel, …