D needed to hire a ship that was near ship X which was in danger and therefore agreed to hire a ship from P, which, relying on a TP, both D and P considered was near X. In fact it was not. D refused to pay claiming the contract was void on the grounds of common mistake. CA allowed P’s claim for payment.
Lord Phillips MR: For a common mistake to void a contract the following five conditions are needed: “(i) there must be a common assumption as to the existence of a state of affairs; (ii) there must be no warranty by either party that that state of affairs exists; (iii) the non-existence of the state of affairs must not be attributable to the fault of either party; (iv) the non-existence of the state of affairs must render performance of the contract impossible; (v) the state of affairs may be the existence, or a vital attribute, of the consideration to be provided or circumstances which must subsist if performance of the contractual adventure is to be possible.” The test is narrow, as demonstrated by the examples Lord Atkins gives (see above). He also agrees with Steyn J that the non-existence of the goods leads to an “essentially different” type of contract to the one envisioned. Here, the question is whether the vessels were so far apart as to confound the common assumption and render performance impossible. They were not since, before not paying for the ship in question, D looked for closer ships i.e. that this ship would do if there was nothing better.
McKendrick: The requirement of impossibility shows how narrow this test is.
CA held that there was no “equitable jurisdiction to grant rescission for common mistake in circumstances that fell short of those in which the common law held a contract void.” The HL in Bell did not mention a remedy in equity not because o an oversight but because no such remedy could have been applied. “There is no jurisdiction to grant rescission of a contract on the ground of common mistake where that contract is valid and enforceable on ordinary principles of contract law.” Solle v Butcher cannot stand given the contradictory authority from Bell. To allow it to stand would be to create uncertainty and incoherence as to what the law actually says. The scope of equity means that a less “fundamental” mistake would needed than would be required in ordinary common law, despite the assertion in Solle that it still has to be fundamental. How can there be degrees of fundamental”? It is also not the law’s job to dissolve or vary valid contracts since fraud, misrepresentation and undue influence were all doctrines that dealt with areas of unfairness on more certain terms. It was also uncertain how Denning’s test of “fundamental” mistake varied from Lord Atkin’s test (in Bell on an essentially different” contract).