Testamentary capacity

In the common law tradition, testamentary capacity is the legal term of art used to describe a person's legal and mental ability to make or alter a valid will. This concept has also been called sound mind and memory or disposing mind and memory.

Adults are presumed to have the ability to make a will. Litigation about testamentary capacity typically revolves around charges that the testator, by virtue of senility, dementia, insanity, or other unsoundness of mind, lacked the mental capacity to make a will. In essence, the doctrine requires those who would challenge a validly executed will to demonstrate that the testator did not know the consequence of his or her conduct when he or she executed the will.

Certain people, such as minors, are usually deemed to be conclusively incapable of making a will by the common law; however, minors who serve in the military are conceded the right to make a will by statute in many jurisdictions. In South Africa, however, one acquires testamentary capacity at the age of 16 years.

The requirements for testamentary capacity are minimal. Some courts have held that a person who lacked the capacity to make a contract can nevertheless make a valid will. While the wording of statutes or judicial rulings will vary from one jurisdiction to another, the test generally requires that the testator was aware of:

The legal test implies that a typical claimant in a will contest is a disgruntled heir who believes he or she should have received a larger share than they did under the will. Once the challenging party meets the burden of proof that the testator did not possess the capacity, the burden subsequently shifts to the party propounding the will to show by clear and convincing evidence that the testator did have the requisite capacity.

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