Barton v Armstrong [1973]

Barton v Armstrong [1973] UKPC 27 is a Privy Council decision heard on appeal from the Court of Appeal of New South Wales, the court addressed issues related to duress, specifically focusing on the ability of a person to avoid a contract entered into under physical duress.

Alexander Barton, the managing director of Landmark Corporation Ltd, executed a deed in which the company would pay $140,000 to Alexander Armstrong, a NSW state politician, and purchase his shares for $180,000. Armstrong was the chairman of the board. It was found by Street J that Armstrong had indeed threatened Barton's life. However, the NSW Court of Appeal held that Barton had failed to prove that the threat had caused him to make the contract.

The Judicial Committee of the Privy Council provided advice that Barton could avoid the contract on the grounds of duress, even if he might have agreed to the deal independently of the duress. Lord Cross, Lord Kilbrandon, and Sir Garfield Barwick held that physical duress need not be the main reason for entering into an agreement; it just has to be one reason among others. Lord Cross asserted that the same rule should apply for duress as in misrepresentation, stating that if threats were a reason for Barton's execution of the deed, he is entitled to relief, even if he might have entered into the contract without the threats.

In dissent, Lord Wilberforce and Lord Simon agreed on the law but found no duress on the facts. They argued that threats needed to be at least one reason for entering into the contract. They explained that the law distinguishes between legitimate and illegitimate means of obtaining consent, with some means, such as duress, coercion, fraud, undue influence, abuse of confidence, falling into the category that the law does not accept as a valid reason for voluntary action.

The three tests for physical duress outlined by Lord Wilberforce and Lord Simon include showing that illegitimate means of persuasion were used, demonstrating that these illegitimate means were a reason for entering into the contract (not necessarily the main reason), and providing honest and accepted evidence.

This case establishes that physical duress can render a contract voidable, even if the duress was not the primary reason for entering into the contract, affirming the importance of protecting individuals from agreements induced by illegitimate pressure or threats.
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