## Facts

- Barton and Armstrong were major shareholders in a company.
- Barton agreed to purchase Armstrong’s interest in the company by executing a deed.
- Barton alleged that Armstrong threatened to murder him if he did not agree to the buyout.
- At first instance, the trial judge rejected Barton’s claim, finding that commercial necessity was the primary reason for entering the contract, not the threats.

## Issues

1. Whether a contract can be set aside for duress to the person if threats were a factor, but not the sole or primary reason, for entering the agreement.
2. Whether the burden of proof falls on the person alleged to have made the threats to show that their threats had no effect on the complainant’s decision.
3. How the standard of causation and burden of proof for duress to the person differs from economic duress and duress to goods.

## Decision

- The Privy Council overturned the trial judge's decision, holding that the threat need only be one reason (not the sole or principal reason) for entering into the contract to establish duress to the person.
- The burden of proof rests on the party alleged to have made the threats: they must prove their threats contributed nothing to the complainant’s decision.
- The case distinguished duress to the person from economic duress, noting that economic duress requires a more demanding standard of causation and the burden of proof remains with the party alleging duress.

## Legal Principles

- Duress to the person voids a contract if the threat was a reason, among others, for entering it; the cause need not be predominant.
- Once a threat is shown to have influenced the decision, the burden shifts to the defendant to show that the threat was inconsequential.
- The standard for causation and proof is less onerous for duress to the person than for economic duress, where the claimant must show the illegitimate pressure was a significant cause.
- The rationale for this protective approach is the unfairness and seriousness of threats to personal safety.

## Conclusion

The Privy Council in Barton v Armstrong [1976] AC 104 established that contracts entered under threats of violence are voidable if the threats were a factor in the decision, with the burden on the defendant to prove the threats had no effect. This case sets a lower causation threshold for duress to the person than for economic or property duress, strengthening legal protection against coercion involving threats to personal safety.

Barton v Armstrong [1976] AC 104 (PC)