NON EST FACTUM (LAWS202)

Non est factum

That is not my deed defence for fundamental mistake about document

Purpose of non est factum

Protects signers misled about nature/effect of document

Effect of successful non est factum

Document void ab initio

Signature rule (L'Estrange v Graucob)

Signature binds even if document not read

Relationship to signature rule

Non est factum is an exception

Key requirement

Mistake about character or effect of document

Non

qualifying mistake

Gallie v Lee (Saunders v Anglia Building Society)

Leading authority on modern test

Gallie test

Document fundamentally different in substance or kind from intended

Element 1

Belief document was something different

Element 2

Difference relates to character/effect of document

Element 3

Mistake caused by another person’s misleading conduct

Element 4

Signer not negligent

Element 5

Legal advice weakens defence

Source of mistake

Must be counterparty or their associate

Self

induced mistake

Fraud alone

Not enough for defence

Required fraud

Fraud as to nature/effect of document

Negligence effect

Defence fails if careless

Bradley West v Keeman

Defence failed; misunderstanding not enough

Keeman principle

Lack of understanding alone insufficient

Radius Residential Care v Krishna

Defence succeeded on guarantee misunderstanding

CF Asset Finance v Okonji

Defence failed due to carelessness

Core test

Fundamental mistake + misleading conduct + no negligence