Dobinson v Crabb

The High Court of Australia considered an appeal from a decision of the Supreme Court of New South Wales in a dispute between the appellant, Dobinson, and the respondent, Crabb. The core of the disagreement concerned the interpretation and enforceability of a deed of settlement entered into by the parties, which aimed to resolve a prior dispute regarding a property transaction.

The central legal question before the High Court was whether the deed of settlement, which contained a release of certain causes of action, was valid and enforceable, or whether it was vitiated by a fundamental mistake as to the existence of the rights being released. Specifically, the court had to determine if the parties had proceeded on a common assumption that certain legal rights existed, and if the falsity of that assumption rendered the deed void.

The High Court, in a joint judgment, held that the deed of settlement was voidable due to a fundamental mistake. Their Honours reasoned that the parties had entered into the deed on the shared, but erroneous, belief that the respondent possessed certain legal rights which were then released by the appellant. The court applied the principles of common law concerning mistake, particularly the doctrine of common mistake, which can render a contract voidable where both parties share a mistaken assumption about a fundamental aspect of the contract. The court distinguished this situation from cases where the mistake relates to the quality of the subject matter, emphasizing that here the mistake concerned the very existence of the rights being compromised.

Consequently, the High Court allowed the appeal, setting aside the deed of settlement. The parties were to be restored to their original positions, and the prior dispute was remitted for determination on its merits.