In order to understand the themes of proprietary estoppel cases, it is important to understand the concept of ‘unconscionability’. This is a word used in litigation to describe conduct that does not conform to the dictates of conscience. When something is judged as unconscionable, a court will refuse to allow the perpetrator of the conduct to benefit.
In contract law an unconscionable contract is one that is unjust or extremely one-sided in favour of the person who has the superior bargaining power. Unconscionable conduct can also be found in acts of fraud and deceit, where there is a deliberate misrepresentation of fact which deprives someone of a valuable possession.