Non Est Factum in UK Law

The plea of non est factum is a plea which must necessarily be kept within narrow limits. Much confusion and uncertainty would result in the field of contract and elsewhere if a man were permitted to try to disown his signature simply by asserting that he did not understand that which he had signed. Furthermore, although the expression is a convenient paraphrase of the plea, it is not enough to assert that "the mind did not go with the pen".

I cannot accept Mr. Eady's submission that there is great difference between signing blind a completed document the contents of which one has not read and signing a printed document, as here, with the blanks for the particular transaction not filled in but agreeing to, or authorising, another to fill in those blanks and the figures later.

If the deed was not his deed at all, (non est factum) he is not bound by his signature any more than he is bound by a forgery. The document is a nullity just as if a rogue had forged his signature. If a person pays out money or lends money on the faith of it, not knowing of the fraud or mistake, he can rely on the document and enforce it against the maker. It avails the maker nothing, as against him, to say it was induced by fraud or mistake.

Where a fraudster has tricked, first, the signer of the document, in order to induce the signature, and then some third party, who is induced to rely on the signed document, which of the two victims is the law to prefer? The authorities indicate that the answer is, almost invariably, the latter. The signer of the document has, by signing, enabled the fraud to be carried out, enabled the false document to go into circulation.

If it is voidable, then it may be capable of being set aside at the suit of a beneficiary, but this would be subject to equitable defences and to the court's discretion. The trustees' duty to take relevant matters into account is a fiduciary duty, so an act done as a result of a breach of that duty is voidable. Fiscal considerations will often be among the relevant matters which ought to be taken into account.

Now let me say at once that in the vast majority of cases a customer who signs a bank guarantee or a charge cannot get out of it. No bargain will be upset which is the result of the ordinary interplay of forces. He agrees to pay a high rent to a landlord just to get a roof over his head. He borrows it from the bank at high interest and it is guaranteed by a friend. Parliament has intervened to prevent moneylenders charging excessive interest.

By virtue of it, the English law gives relief to one who, without independent advice, enters into a contract or transfers property for a consideration which is grossly inadequate, when his bargaining power is grievously impaired by reason of his own needs or desires, or by his own ignorance or infirmity, coupled with undue influences or pressures brought to bear on him by or for the benefit of the other.