Legal Definitions - non est factum

Non Est Factum is a legal defense used when a person claims that a document they signed should not be legally binding on them because they fundamentally misunderstood its nature or contents at the time of signing. This defense is typically raised when the signatory was misled about the document's true character, or when they lacked the capacity to understand it, often due to fraud, illiteracy, or a significant mental impairment, making the document, in a legal sense, "not their deed."

Here are some examples illustrating this concept:

• Example 1: Misleading an Elderly Individual

  An elderly woman, Mrs. Davies, who is experiencing early signs of cognitive decline, is approached by a distant relative. The relative presents her with a document, assuring her it's merely a form to update her emergency contact information. Trusting the relative, Mrs. Davies signs it without reading. Later, she discovers the document was actually a deed transferring ownership of her valuable antique collection to the relative. Mrs. Davies could argue non est factum, asserting that she never intended to transfer her property and fundamentally misunderstood the document's true nature due to the relative's deception and her own diminished capacity.

• Example 2: Language Barrier and Deception

  Mr. Chen, a recent immigrant who speaks very little English, is looking to rent an apartment. The landlord provides him with a stack of English-language documents to sign. The landlord verbally assures Mr. Chen, through a few translated words, that these are standard lease agreements. Mr. Chen signs them, believing he is agreeing to a typical rental contract. Months later, he discovers one of the documents he signed was a personal guarantee for a business loan taken out by the landlord, making Mr. Chen personally liable for a large debt. Mr. Chen could invoke non est factum, arguing that he fundamentally misunderstood the nature of the guarantee document due to the language barrier and the landlord's misrepresentation, making it "not his deed."

• Example 3: Mistake as to the Type of Document

  A community activist, Ms. Rodriguez, is collecting signatures for a petition to build a new park. She approaches Mr. Henderson, who is visually impaired and relies on others to read documents to him. Ms. Rodriguez asks Mr. Henderson to sign what she describes as "the park petition." Unbeknownst to Mr. Henderson, the document he signed was actually a binding agreement to donate a significant sum of money to the park project, disguised within the petition papers. Mr. Henderson could claim non est factum, asserting that he believed he was merely supporting a cause with his signature, not entering into a financial obligation, and therefore fundamentally misunderstood the document's true legal effect.