Families often ask me whether a loved one with dementia can still make or change a will. As a geropsychologist who does capacity evaluations and neuropsychological assessments with older adults, I work at the intersection of aging, cognition, and decision-making capacity. I have over a decade of experience doing neuropsychological and capacity assessments, and I have seen many people in many situations for these types of evaluations. Understanding the legal thresholds for “testamentary capacity” is important for older adults and families facing this concern.
What Is Testamentary Capacity?
In legal terms, testamentary capacity refers to the mental ability required to make a valid will. Courts in California generally look for four key abilities:
Understanding the nature of a will: The person must grasp that a will distributes their property after death.
Knowing the extent of their assets: They don’t need to recall every bank account number, but they should have a reasonable sense of what they own (like property, investments, and so on).
Recognizing potential beneficiaries: They must know who might logically inherit their estate, such as their spouse, children, or other close relations.
Making rational decisions: They must be able to weigh these factors and express a clear choice with a rationale that makes sense and is consistent with what we know of their values.
Dementia and Capacity: Not Always Black and White
Dementia is a progressive condition, but capacity is not all-or-nothing. Key points:
Cognition can fluctuate over days or weeks: Some individuals have “lucid intervals” where their thinking is clear enough to meet legal standards.
Diagnosis ≠ incapacity: A dementia diagnosis alone does not automatically invalidate a will or mean a person lacks capacity.
Context counts: Courts often consider medical records, neuropsychological evaluations, and witness testimony to determine capacity at the time the will was signed. This is where having a geropsychologist with expertise in capacity assessment involved can cover a lot of bases. I conduct a thorough and comprehensive evaluation with the legal standards in mind, so there are no big unanswered questions
The Role of Geropsychologists
Geropsychologists are often asked to evaluate whether someone has the cognitive ability to make legal decisions. This may involve:
Clinical interviews to assess understanding of assets and beneficiaries.
Collateral interviews with people who know the older adult and their situation, like family members, caregivers, attorneys, and accountants who are involved.
Cognitive testing to measure memory, reasoning, and judgment.
Review of medical or financial records to support a medical opinion about capacity.
Documentation that provides courts with objective evidence of capacity (or lack thereof).
Such capacity evaluations can protect vulnerable individuals from undue influence while also honoring their autonomy when capacity is intact.
Legal Safeguards
Attorneys and courts often use additional safeguards when dementia is present:
Medical affidavits: Physicians or psychologists may provide written opinions on capacity.
Witnesses: Neutral parties may be present during will signing to attest to lucidity.
Video recordings: Some families choose to document the process to reduce later disputes.
Practical Guidance for Families
If you’re supporting a loved one with dementia who wishes to change their will:
Seek professional evaluation early to establish capacity. I am always happy to consult in these cases. They can be tricky to navigate without guidance from attorneys and psychologists who specialize in capacity.
Document the process carefully to prevent future challenges.
Balance autonomy and protection—respect your loved one’s wishes while ensuring they are not exploited.
Final Thoughts From a Geropsychologist in Los Angeles
The question of whether dementia patients can change their will is nuanced. The legal threshold is not about perfect memory or flawless cognition, and a diagnosis of any kind does not automatically mean a person lacks capacity. The legal threshold for capacity is focused on whether the individual can demonstrate understanding, reasoning, and intent at the time of the decision. With careful evaluation and documentation, many people with mild or moderate dementia may still meet the standard for testamentary capacity.
As a geropsychologist in South Bay, CA, my role is to help families and courts navigate these complexities with compassion and clarity, ensuring that dignity and justice remain at the center of the process.
Get CLear Guidance With a Testamentary Capacity Assessment in Los Angeles, CA
When questions arise about a loved one’s ability to make or change a will, a testamentary capacity assessment can provide clarity, protection, and peace of mind. With professional evaluation, families and legal teams gain informed guidance that helps reduce conflict and supports sound decision-making.
Conversations about wills and decision-making in the context of dementia can feel emotionally heavy, but they are also deeply important. These discussions go beyond paperwork—they center on honoring a person’s values, wishes, and autonomy while ensuring decisions meet legal standards. As a trusted geropsychologist in Los Angeles, CA, Dr. Stacy Reger offers a careful, respectful approach to navigating these sensitive situations. Her work helps families and professionals understand cognitive capacity, communicate more effectively, and move forward with confidence and compassion.
Take the next step toward clarity and confidence:
Work with a geropsychologist in Los Angeles for testamentary capacity evaluations
Create a plan that balances legal insight with emotional care and understanding
Other Services Dr. Reger Provides in California
When uncertainty arises about a loved one’s ability to make or change a will, a testamentary capacity assessment can provide essential clarity and reassurance. These evaluations help families and professionals understand cognitive functioning while supporting decisions that are both legally sound and emotionally respectful.
As a geropsychologist in Los Angeles, CA, Dr. Reger brings a calm, compassionate approach to situations involving estate planning, cognitive change, and end-of-life decision-making. She helps adult children and aging parents navigate these complex conversations with care—ensuring that personal values, intentions, and concerns are thoughtfully considered. Through comprehensive neuropsychological evaluations, she assesses memory, reasoning, judgment, and decision-making abilities that may impact a person’s capacity to understand and express testamentary wishes.
In addition to testamentary capacity evaluations, Dr. Stacy Reger conducts a range of med-legal and clinical assessments, including workers’ compensation evaluations, pre-surgical cognitive screenings, and other neuropsychological services that support informed planning. Her work helps families, attorneys, and fiduciaries determine appropriate next steps with confidence and clarity.
Dr. Reger also offers therapy and consultation for older adults and caregivers facing emotional, relational, or identity challenges related to aging and independence. She collaborates with families, professionals, and community organizations through education, training, and presentations designed to improve communication and decision-making. To learn more about cognitive health, aging, and navigating sensitive family discussions, visit Dr. Reger’s blog for additional resources.