Capacity to Write a Will

A will is a document written during the life of a person, which expresses what that person (the testator) wants done with his or her property after death.

Because writing a will is such a personal and important decision, the law has enacted some safeguards to ensure that the testator is acting of his or her own free will, and knows what he or she is doing.

A will, or a provision in a will, which is the result of fraud, duress, undue influence, or mistake is not valid. For a will, or a provision in it, to be invalid because of fraud, it must be shown that somebody made a material misrepresentation of fact to the testator, and they intended for that person to rely on that misrepresentation when writing the will. It must also be shown that the provision in question is, in fact, a result of the fraud.

For example, if somebody marries a wealthy widow, hoping to get written into her will, and is, in fact, legally married to someone else, this is fraud: he lied about being able to marry her, and she relied on her belief that their marriage was valid when writing the will. Any provision leaving property to the fraudster will not be enforced.

Duress involves the use of force or the threat of force in getting someone to write a will. A simple example would be putting a gun to a person’s head, and telling them to write a will in a certain way. Anything in the will that was induced by this duress will be invalidated.

Undue influence is a little more complex. Undue influence exists when a will is brought about through inappropriate pressure from an outside party. The influence must be so strong that it actually overcame the testator’s free will, and substituted his intent for that of someone else. Undue influence is usually committed by a person in a relationship of trust with the testator, such as a family member.

In addition to the above external events that can invalidate a will, internal factors can do so as well. If the testator lacks sufficient mental capacity – to the point that he or she cannot understand that a will is being written, and the consequences of the will, then the will is invalid. A person must be of sound mind to make a will.

Courts will strongly presume that a person had the requisite mental capacity to make a will, and overcoming this presumption is difficult, and requires very convincing evidence. It requires a showing that, at the time of the execution of the will, the testator basically had no idea what he or she was doing, and could not comprehend the consequences of his or her actions.

A will might also be invalid if the testator suffers from an “insane delusion”. This is different from a complete lack of mental capacity. It is a delusion, unsupported by any facts, concerning a particular person or entity. It can only invalidate the provisions in the will that are affected by the delusion. It can invalidate an entire will, if the whole thing was influenced by the delusion.

A simple example would be writing a family member out of the will because the testator thinks that he or she has been replaced by a space alien. Of course, in reality, the beliefs are usually not so outlandish.

In one real-life case, a woman left her entire estate to The National Women’s Party. It was later revealed that she harbored, without any apparent logical reason, a belief that the entire male sex was conspiring against her, and was solely responsible for all of the world’s ills, and that the National Women’s Party was the only group that could fix this. The court found that her beliefs were motivated by an insane delusion, and that her will was a result of this delusion, and invalidated the will because of that.

Ken LaMance is Associate General Counsel for – the easiest way to Find a Lawyer Online. Ken, a well respected San Francisco Attorney, has worn many hats at LegalMatch – from litigator to project manager. He has been instrumental in creating LegalMatch’s Law Library
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