Clear threat, problem of causation:

• threats of physical violence/death being made
• but also good commercial benefits of entering contract
  HELD: threats were sufficient inducement (maj); threats were not significant role (min)
  (Barton v Armstrong [1976])

Other forms of duress involving persons

• to arrange for criminal prosecution/ imprisonment/ continued detention
• to disclose embarrassing/ incriminating information (Tam Tak Chuen v Khairul bin Abdul Rahman)
• redeployment from elite army squad to regular unit unless confidentiality agreement was signed: loss of prestige and social life, embarrassment, lower pay (R v A-G of England and Wales)

Duress of goods

• seizure of V's goods (Maskell v Horner)
• refuse to release V's goods
• threat to damage V's goods (The Siboen and The Sibotre, obiter)

Threatening to terminate a contract, or to refuse to perform (in whole or in part) a legal obligation:
North Ocean Shipping Co Ltd v Hyundai Construction Co Ltd (The Atlantic Baron) [1979] QB 705 (threat to refuse to complete construction and deliver ship to V)
The Siboen and The Sibotre (refusal by T to pay full charter rate of hire to V: no duress on facts).
D&C Builders Ltd v Rees [1966] 2 QB 617 at 625 per Lord Denning MR (T insisting on paying lesser sum in discharge of debt owed to V)
Pao On v Lau Yiu Long [[1980] AC 614 (threat by T to refuse to complete transaction with a public company, in which V were major shareholders; no duress on facts).
B & S Contracts and Design Ltd v Victor Green Publications Ltd [1984] ICR 419 (T refusing to perform unless V shared cost of meeting demands by T’s striking workers) but cf Sharon Global and Williams v Roffey Bros

Duress and consideration

• can argue on either ground
• practical benefit subject to duress (Williams Roffrey though on the facts it was not duress since it was honest statement of fact)

(1) look at threat and demand itself

• any threat of unlawful conduct (criminal/tortious/statute) is prima facie illegitimate (The Universe Sentinel; R v A-G for England and Wales; Barton v Armstrong)
• considerations of statutory policy (The Universe Sentinel and cf The Evia Luck)
  (2) good faith/ bad faith? (only suggested, no case successful)

Threat to breach contract

• consider several factors, public policy
  (1) Characterisation
• threat or genuine, factual statement?
• did T initiate demand/alternative suggested by V/developed jointly? (Sharon Global)
  (2) Good faith or bad faith conduct by T (Sharon Global)
  (3) Existence/absence of a reasonable commercial basis for demand by T
• not customer's responsibility to pick up half the bill demanded by striking employees (case?)
  

Some factors

• “whether [the conduct] is morally or socially unacceptable” (CTN Cash & Carry at 719)
• whether the threat involves some collateral, improper motive or abuse of process, as contrasted with a genuine attempt to enforce legal rights (compare Tam Tak Chuen at [52], [57] and Lee Kuan Yew at [42]-[44] (bona fide and not vexatious)).
• good faith/bad faith? (CTN Cash and Carry)
• justified/reasonable demand (R v A-G for England and Wales)
• unconscionability? (controversial: Tan Tak Chuen cf E C Investment; concerns of vagueness)

Weird cases:
Tam Tak Chuen -> used standard for threat to duress of person
EC Investment -> accepting onus on T for economic duress too

Proving the pressure led to compliance with the demand
Factors:
(1) protest? but not fatal (Tam Tak Chuen)
(2) alternative course open to V?
(3) gravity of consequences of threat?
(4) did V have access to independent legal advice?
(5) actions of V after threat, what steps did V take to avoid the contract once the pressure had abated; length of time? (overlaps with issue of affirmation)