Chapter 10: Mistakes Flashcards
1 Introduction
‘Mistake’ has a narrower meaning in contract law than it does in its ordinary English meaning. If a contract is affected by mistake in the way the word is used in contract law (called an ‘operative’ mistake), then there are serious consequences: the contract is void meaning the contract will be declared a nullity from its beginning, or to use the legal Latin term, the contract is void ab initio.
Void v Voidable
Void’ is different to ‘voidable’ – the latter means that the contract can be brought to an end/avoided, but until that happens, it remains in force – it is not declared a nullity from the beginning.
Operative mistake: A mistake which is recognised in the law of contract as preventing a contract from taking legal effect – the contract will be void from the outset.
Void: A contract which is void has no legal effect from the outset.
Law of Mistake
The law of mistake is therefore an exception to the general rule of contract that parties are bound by the terms of their agreement and must rely on the contract for protection from the effect of facts unknown to them.
At the heart of the concept of mistake is the idea that the parties have not truly reached an agreement: either the parties cannot be said to have reached agreement because of the mistake, or the mistake renders the agreed contract something other than that which was intended.
2.1 Common mistake
Common mistake occurs where both parties to an agreement are suffering from the same misapprehension. It is necessary to consider whether the underlying common mistake is sufficiently fundamental to
affect the validity of the contract.
2.1.1 Common mistake as to a fact or quality fundamental to the agreement
In the absence of contractual misdescription, the general proposition is that mistake about the quality of goods does not void the contract. This is the case even if the mistake as to quality affects the utility of the goods to the buyer, or, alternatively, affects the value of the goods in question. It has been suggested that there is a limited category of cases where the mistake is so severe that
the contract will be void for mistake as to quality
Restrictive approach to common mistake
It could be a question of whether the mistake is such that the subject matter is
‘essentially different’ from that intended (Bell v Lever Brothers [1932] AC 161), or alternatively whether the mistake renders the assumed performance ‘impossible’, or whether the subject matter is rendered ‘radically different’.
Leaf v International Galleries [1950] 2 KB 86.
The restrictive approach to common mistake in Bell v Lever Brothers was endorsed in Leaf v International Galleries [1950] 2 KB 86. Although Leaf’s action was in misrepresentation, the court stated, obiter, that a claim in mistake in relation to a painting both the buyer and seller mistakenly believed to be a Constable would fail. The parties had contracted for the sale of a painting, and this is what the buyer received under the contract. It is worth noting, however, that a remedy in
misrepresentation may be available in such circumstances.
Circumstances where common mistake will not operate
(a) The mistake is not sufficiently fundamental.
(b) One party is at fault.
(c) The contract makes provision for the issue.
2.2 Mutual mistake
Mutual mistake occurs where both parties are mistaken but they are mistaken about different things. In other words, they have negotiated at cross purposes.
Example: Mutual mistake
Where A and B have negotiated completely at cross purposes, whereby A is offering one thing whilst B is accepting another, it cannot be said that they were ever in agreement. Genuine mutual consent is obviously lacking. Such a contract will be void. For example, A agrees to sell a horse to B. A intended to sell his chestnut horse, but B thought he was agreeing to buy A’s grey horse. Needless to say, the colour of the horse was not mentioned during the formation of the contract.
Objective Test based on reasonable Third Party
The court will employ an objective test and decide what a reasonable third party would believe the agreement to be, based on the words and conduct of the parties themselves. Using this test, it may be decided that the agreement was that
which A understood it to be or that which B understood it to be, or it may be decided that no meaning can be attributed to the agreement at all. The result is that if, from the available evidence, a reasonable person would infer the existence of a contract in a given sense, the court will hold that a contract in that sense is binding upon both parties, notwithstanding a material
mistake.
2.3 Unilateral mistake
Unilateral mistake occurs where only one party is mistaken and the other party knows, or is deemed to know, of the mistake.
Where unilateral mistake has occurred, the acceptance does not correspond with the offer, and there is consequently no real agreement reached.
Example 1: Unilateral mistake as to the expression of intention
Where the offeror makes a material mistake in expressing their intention, and the other party knows, or is deemed to know, of the error, the mistake is likely to lead to the contract being void.
Hartog v Colin & Shields [1939] 3 All ER 566
The defendants entered into a contract to
sell 3,000 Argentinian hare skins to the claimants. By mistake, they offered them for sale at 10d per pound, instead of the 10d per piece they intended. The negotiations had proceeded on the basis of a price per piece (there being three pieces per pound). As a result, the court found that the defendants’ offer was not an accurate reflection of their true intention and that there was no
binding contract. The claimants could not ‘snap up’ an offer when that party was aware that the other had made a mistake relating to the offer terms.
Example 2: Unilateral mistake as to the nature of the document signed
The general rule is that a person is bound by the terms of any instrument which they sign or seal even though they did not read it or did not understand its contents: L’Estrange v Graucob [1934] 2 KB 394. An exception to this general rule arises, under certain circumstances, where a person signs or seals a document under a mistaken belief as to the nature of the document. Where a person signs a document or executes a deed in such instances, they may raise the defence of non
est factum (‘it is not my deed’).
Plea of non est factum
(a) The blindness, illiteracy, or senility of the person signing; or
(b) A trick or fraudulent misrepresentation as to the nature of the document, provided that
person took all reasonable precautions before signing.