According to California Probate Code §6100.5, an individual lacks testamentary capacity if he or she is unable to do any of the following at the time of the signing of the document: Understand the nature of the action being undertaken and its effects.
Clinical Neuropsychologists are uniquely trained to evaluate Civil Capacity issues. Examples of Civil Capacity may include the question of whether a parent with possible dementia can change her power of attorney and her will or a young adult with a traumatic brain injury can manage a large financial settlement. These cases require a careful assessment of cognitive and psychological functioning, medical issues, family dynamics; sometimes in the context of family conflicts.
Most cases that require an evaluation of civil capacity, are raised in situations where the patient has dementia, where executive functions are considered to be adversely affected.
Testamentary Capacity refers to an individual's ability to make a valid will. In these cases, four functional abilities must be considered:
Whether the testator understood the purpose of the document she or he was signing;
Whether the individual had a general understanding of the property she or he intends to distribute;
Whether the individual recalled the objects of his or her bounty (beneficiaries), and
Whether or not a desire to leave a property to persons was reasonable or whether it was the result of an "insane delusion".