MrGimpy & Proudfoot, I am not, & never have been, a practising lawyer: I'm just a Manchester mum with an interest in legal history, so would like to bow to your superior knowledge. But I do know that you are of both wrong in stating that promissory estoppel in English law is "a shield, not a sword". Please read Amalgamated Investment and Property Co Ltd -v- Texas Commerce International Bank Ltd (It's a 1982 case, so the passage of 31 years should mean that it has seeped under whichever legal rock you are using for shelter....).
This is a really neat case because Denning, (by then MR & sitting in CA, author of the English law variant of PE in High Trees House ) openly states that Promissory Estoppel can be used as a sword as well as a shield:
When the parties to a transaction proceed on the basis of an underlying assumption ? either of fact or of law ? whether due to misrepresentation or mistake makes no difference ? on which they have conducted the dealings between them ? neither of them will be allowed to go back on that assumption when it would be unfair or unjust to allow him to do so. If one of them does seek to go back on it, the courts will give the other such remedy as the equity of the case demands.
This has some kool implications for the current (teeth) case:
First, "a shield, not a sword" is out-of-date and is, anyway, no better than a summary of some well-known decided cases, and not a hard-faced legal principle; and the joy of our legal system is that it is capable of evolving. A perfect example of this can, ironically, be found in the history of PE: the American Law Institute rewrote its "Restatement of the Law of Contract" (essentially a device for spreading "best practice" between the states, all of whom maintain their own legal system: allows Wyoming etc to keep up) in 1929 to include the use of PE as a "sword", based on the 2 NY / Cardozo cases mentioned.
Second, the <span class="italic">"English Country Bumpkin Solicitor"</span> (ECBS) position that you both adopt has no internal logic, whereas the original NY statement has very strong internal logic. There are plenty of English market town solicitors who would not think of daring to stretch PE beyond the very tame limits of <span class="italic">Hightrees House</span> ; but there are also plenty of others who are quite capable of seeing that the case we are talking about (the teeth!) is a very good fit to the full definition of PE as defined by CA in 1982, supported by NY / ALI.
The Denning / Cardozo nexus is particularly important: Denning wanted to be seen as the English Cardozo, not just as an English judge who referred to Cardozo's judgements (that role had been taken by MacMillan in 1932 in Donoghue v Stevenson, when he said that Cardozo (in MacPherson v Buick ) had "...stated the law exactly as I should aim to state it).
In Hightrees House, Denning was keen to be seen as the Cardozo-like genius who had introduced a novel concept to English law, so did not cite the cases from which he drew inspiration (the NY ones stated); even so, his original definition of PE as:
a promise was made which was intended to create legal relations and which, to the knowledge of the person making the promise, was going to be acted on by the person to whom it was made and which was in fact so acted on
offers no suggestion that this intended to be a purely defensive (shield) doctrine.
Those of you with a genuine interest in legal history should set aside a few hours to ask me about the significance to English law of Denning & Glanzer v Shepard ...