Contracts: invalidity
A practice note that explains the grounds for challenging a contract's validity, outlining the rules that may make a contract void or unenforceable, on grounds such as illegality or public policy (ex turpi causa), or voidable for duress or undue influence. It provides an overview of the key differences between void and voidable contracts, outlining the circumstances that can render an agreement unenforceable from its inception or subject to rescission. The discussion on illegality details the significant policy-based approach established in Patel v Mirza [2016] UKSC 42 and later refined in Stoffel and Co v Grondona [2020] UKSC 42. The note also covers when a contract is voidable due to duress, including economic duress as considered in Pakistan International Airline Corporation v Times Travel (UK) Ltd [2021] UKSC 40, and undue influence. It further highlights how these principles affect the enforceability of commercial agreements.
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