To establish that a contract was unconscionable, a party had to have made an unconscientious use of its superior position or superior bargaining power to the detriment of someone suffering from some special disability or disadvantage. This weakness had to be exploited in some morally culpable manner, leading to an oppressive transaction. There must be some impropriety, both in the conduct of the stronger party and in the terms of the transaction itself, but ‘the former may often be inferred from the latter in the absence of an innocent explanation’.
Peter Millett QC J said: ‘It is probably not possible to reconcile all the authorities, some of which are of great antiquity, on this head of equitable relief, which came into greater prominence with the repeal of the usury laws in the 19th century. But if the cases are examined, it will be seen that three elements have almost invariably been present before the court has interfered. First, one party has been at a serious disadvantage to the other, whether through poverty, or ignorance, or lack of advice, or otherwise, so that circumstances existed of which unfair advantage could be taken: see, for example, Blomley v Ryan (1954) 99 CLR 362, where, to the knowledge of one party, the other was by reason of his intoxication in no condition to negotiate intelligently; secondly, this weakness of the one party has been exploited by the other in some morally culpable manner: see, for example, Clark v Malpas (1862) 4 De G.F. and J. 401, where a poor and illiterate man was induced to enter into a transaction of an unusual nature, without proper independent advice, and in great haste; and thirdly, the resulting transaction has been, not merely hard or improvident, but overreaching and oppressive. Where there has been a sale at an undervalue, the undervalue has almost always been substantial, so that it calls for an explanation, and is in itself indicative of the presence of some fraud, undue influence, or other such feature. In short, there must, in my judgment, be some impropriety, both in the conduct of the stronger party and in the terms of the transaction itself (though the former may often be inferred from the latter in the absence of an innocent explanation) which in the traditional phrase ‘shocks the conscience of the court,’ and makes it against equity and good conscience of the stronger party to retain the benefit of a transaction he has unfairly obtained.’
Peter Millett QC J
 1 All ER 944,  1 WLR 87
England and Wales
Cited – Clark v Malpas 25-Apr-1862
The court found a contract to be an unconscionable bargain where a poor and illiterate man was induced to enter into a transaction of an unusual nature, without proper independent advice, and in great haste; and the resulting transaction has been, . .
Cited – Blomley v Ryan 28-Mar-1956
(High Court of Australia) Equity – Contract for sale and purchase of grazing property – Suit for specific performance brought by purchaser – Vendor aged and affected by long bout of rum drinking – Claim to set aside contract – Unconscionable bargain . .
Appeal from – Alec Lobb (Garages) Ltd v Total Oil Ltd CA 1985
The court was asked whether the terms of a lease and lease back amounted to an unconscionable bargain and was unenforceable.
Held: The court affirmed the decision at first instance, but emphasised the need for unconscientious behaviour rather . .
Cited – Chagos Islanders v The Attorney General, Her Majesty’s British Indian Ocean Territory Commissioner QBD 9-Oct-2003
The Chagos Islands had been a British dependent territory since 1814. The British government repatriated the islanders in the 1960s, and the Ilois now sought damages for their wrongful displacement, misfeasance, deceit, negligence and to establish a . .
Cited – Portman Building Society v Dusangh and Others CA 19-Apr-2000
The defendant sought to set aside an order for possession under a mortgage.
Held: Where a case was strong enough on its face in terms of conduct and terms, unconscionable conduct could be inferred if there was no explanation offered to . .
Cited – Boustany v Piggott PC 1995
In discussing what was said to be unconscionable contract, the Board accepted that ‘It is not sufficient to attract the jurisdiction of equity to prove that a bargain is hard, unreasonable or foolish; it must be proved to be unconscionable, in the . .
Cited – Strydom v Vendside Ltd QBD 18-Aug-2009
The claimant sought recovery of a sum paid to the defendant as a commission by his union during his claim for personal injuries at work, relying on a term he sought to have implied into his contract, that the costs position should not be . .
Cited – Ramzan v Brookwide Ltd ChD 8-Oct-2010
The claimant owned a flying freehold room butting into the defendant’s property. Whilst the claimant’s property was unoccupied, the defendant broke through into the room, blocked off the door to the claimant’s property, and included the room in the . .
Cited – Jones v Morgan CA 28-Jun-2001
The claimant appealed against an order refusing him enforcement an agreement for the purchase of a one half share in a property. The judge had found the agreement to be unconscionable.
Held: The appeal was dismissed. The judge had wrongly . .
Lists of cited by and citing cases may be incomplete.
Updated: 29 July 2021; Ref: scu.186674