Wills, trusts and estates: Wills: Contest: Testamentary capacity + No-contest clause

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.

Presumption of capacity.

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.

A no-contest clause, also called an in terrorem clause, is a clause in a legal document, such as a contract or a will, that is designed to threaten someone, usually with litigation or criminal prosecution, into acting, refraining from action, or ceasing to act. The phrase is typically used to refer to a clause in a will that threatens to disinherit a beneficiary of the will if that beneficiary challenges the terms of the will in court. Many states in the United States hold a no-contest clause in a will to be unenforceable, so long as the person challenging the will has probable cause to do so.

No-contest clause in wills.

The Uniform Probate Code (UPC) §§ 2-517 and 3‑905 allow for no contest clauses so long as the person challenging the will doesn't have probable cause to do so. The full wording is:

A provision in a will purporting to penalize an interested person for contesting the will or instituting other proceedings relating to the estate is unenforceable if probable cause exists for instituting proceedings.

— UPC §§ 2-517 and 3‑905. 

The UPC has been adopted in several smaller states, including Alaska, Idaho, Montana, and New Mexico, but also by Florida, one of the larger states in population.

Some states allow for "living probate" and "ante mortem" probate, which are statutory provisions which authorize testators to institute an adversary proceeding during their life to declare the validity of the will, in order to avoid later will contests.