Brennan v Bolt Burdon [2005]

Brennan v Bolt Burdon [2005] QB 303 revolved around whether a contract of compromise entered into by the parties was void due to a common mistake.

Brennan, claiming personal injuries caused by a faulty boiler, had initiated legal proceedings against the landlord, Islington Council. Both parties mistakenly believed that the claim was time-barred, leading them to enter into a contract of compromise. However, it later emerged that the claim form's submission on a Saturday was valid, contrary to their initial understanding based on the Anderton case.

The Court of Appeal, led by Maurice Kay LJ, held that the contract of compromise was valid. Kay emphasised that for a common mistake of law or fact to vitiate a contract, it must render performance impossible. In this case, the compromise was always performable, despite the parties' initial doubt about the law. The court highlighted that doubt alone does not constitute a mistake, and the correct understanding of a contract for compromises involves allowing parties to reserve the right to sue pending a subsequent decision.

Sedley LJ, in his dissenting opinion, discussed the common mistake of law. He differentiated the test for a mistake as to the existence of goods from that of a mistake of law, asserting that the latter only renders a contract void if the mistake concerns the legality of the contract. Sedley proposed a different test for mistake of law, questioning whether there would have been an intelligible basis for the agreement had the parties known the law as it is now understood. In the current case, Sedley argued that the contract was not void for common mistake since the parties entered into it with knowledge of the prevailing law and its potential evolution.

Sedley LJ's dissenting stance highlighted the tension between the majority's approach and his view on common mistakes of law. He underscored the conceptual challenge presented by the legal fiction that views the law as an unchanging discovery rather than a development.
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