Contesting a Will Due to Dementia

Emily just received a copy of her mother’s new will. It completely cuts her out, leaving everything to a new “friend” her mother met at a senior exercise class. Emily is devastated, but more than that, she’s deeply worried. Her mother was diagnosed with Alzheimer’s six months ago, and Emily believes she didn’t understand what she was signing when she revised her estate plan. Now, Emily faces a heartbreaking dilemma: how to protect her mother’s wishes, and ensure the will reflects her true intentions, not the influence of someone else. The cost of inaction – allowing a potentially invalid will to stand – could mean losing her mother’s legacy, and years of family history.

When clients come to me with situations like Emily’s, the first thing I emphasize is the importance of acting quickly. California probate law provides a limited timeframe to challenge a will, and missing that window can be fatal to your case. We’ve seen countless instances where a family member suspected foul play, delayed taking action, and then found themselves powerless to correct a manifestly unfair outcome.

What Level of Mental Capacity is Required to Create a Valid Will?

This is the central question in most dementia-based will contests. It’s not about whether your loved one had dementia, but whether they possessed the necessary mental capacity at the time they signed the will. California uses a relatively low threshold for capacity. Probate Code § 6100.5 states that a person is considered of ‘sound mind’ unless they lacked the ability to understand the nature of the testamentary act, the nature of their property, or their relationship to living family members (or suffered from a specific delusion).

This means even someone with mild to moderate dementia could have the capacity to execute a valid will. However, if the dementia was advanced and the person frequently experienced periods of confusion, disorientation, or impaired judgment, that creates a strong argument for incapacity. We look for evidence showing a diminished ability to comprehend the implications of their decisions. This isn’t a question of whether they recognized faces or remembered names; it’s about understanding they are signing a document that disposes of their assets after death.

How Do We Prove Lack of Capacity?

Proving a testator lacked the requisite mental capacity requires more than just a diagnosis of dementia. We need concrete evidence. This could include:

Medical Records: Detailed physician notes documenting the progression of the dementia, including cognitive testing results, descriptions of behavioral changes, and assessments of the individual’s ability to reason and make decisions.
Witness Testimony: Statements from family members, friends, caregivers, and healthcare professionals who observed the testator’s condition around the time the will was signed. Their accounts can paint a picture of the individual’s cognitive abilities and level of awareness.
Lucid Intervals: Evidence of fluctuating cognitive function. Did the testator have periods of clarity interspersed with periods of confusion? A will signed during a confused state is far more vulnerable to challenge.
Unusual Provisions: Does the will contain provisions that are out of character for the testator, or that seem illogical or inconsistent with their prior expressed wishes? This could suggest undue influence or a lack of understanding.

What if a Caregiver Was Heavily Involved?

When a caregiver is also a beneficiary, the situation becomes even more concerning. Probate Code § 21380 creates a presumption of undue influence if a gift is made to a care custodian of a dependent adult. The burden of proof then shifts to the caregiver to prove they did not coerce the senior. If they fail to do so, the gift is invalid, and the caregiver is disinherited – and may be liable for attorney’s fees.

This is a significant legal hurdle for the caregiver, and we often see them struggle to overcome the presumption. Even seemingly benign actions – driving the testator to the attorney’s office, being present during the signing ceremony, or repeatedly discussing the will – can be interpreted as evidence of undue influence.

What About Challenges Based on Forgery or Fraud?

While dementia is a common ground for contesting a will, it’s crucial to differentiate between incapacity and other potential issues. Sometimes the problem isn’t that the testator lacked the mental capacity, but that the will was forged or the result of fraud.

…proving a signature is fake often requires a forensic handwriting expert, whereas proving fraud in the inducement requires evidence that the testator relied on a lie (e.g., ‘your son is stealing from you’) to change their estate plan. These cases require a different approach and often involve more complex evidence gathering.

What is the Deadline to File a Contest?

Time is of the essence. Probate Code § 8270 provides that once the will is admitted to probate, interested parties have a strict 120-day window to file a petition to revoke probate. If you miss this deadline, the will is generally locked in stone, even if it was forged or signed under duress. It’s a harsh rule, but it provides certainty and finality to the probate process.

Throughout my 35+ years practicing as both an Estate Planning Attorney and a CPA, I’ve seen firsthand how devastating a will contest can be for families. But I’ve also seen how crucial it is to protect vulnerable individuals from exploitation and ensure their final wishes are truly honored. As a CPA, I can also help clients understand the tax implications of a will contest, including the potential for a step-up in basis and minimizing capital gains taxes. Understanding these financial aspects is critical to developing a comprehensive legal strategy. I always approach these cases with empathy and a commitment to achieving the best possible outcome for my clients, while respecting the dignity of all involved.

What separates an efficient California probate process from a drawn-out conflict over authority and assets?

California probate is designed to provide court-supervised transfer of property, yet cases often break down when authority is unclear, required steps are missed, or disputes arise over assets, notice, and fiduciary conduct. When the process is misunderstood, families can face avoidable delay, escalating conflict, and increased exposure to creditor issues, hearings, or litigation before the estate can close.

• Escalation: Prepare for probate litigation if agreement fails.
• Document Challenges: Understand the grounds for will contest process.
• Cross-Over: Navigate complex probate and trust disputes.

California probate is most manageable when authority is documented early, assets are classified correctly, and procedure is followed consistently from petition through closing. When the process is approached with realistic expectations about notice, claims, accounting, and dispute risk, the estate is more likely to move toward closure without avoidable conflict or delay.

Verified Authority on California Will Contests

• The 120-Day Statute of Limitations: California Probate Code § 8270
  Time is the enemy in a will contest. Under Section 8270, an interested person may petition the court to revoke the probate of a will, but this petition MUST be filed within 120 days after the will is admitted. Missing this deadline is usually fatal to the case.
• Mental Competency Standard: California Probate Code § 6100.5 (Unsound Mind)
  This statute defines exactly what “mental incompetency” means in probate. It is not just general forgetfulness; the contestant must prove the deceased did not understand the nature of the testamentary act, could not recollect their property, or was suffering from a specific hallucination or delusion that dictated the will’s terms.
• Presumption of Undue Influence (Caregivers): California Probate Code § 21380
  To protect vulnerable seniors, California law automatically presumes undue influence if a will leaves assets to a paid care custodian or the lawyer who drafted the instrument. This shifts the heavy burden of proof onto the accused to prove their innocence.
• No-Contest Clause Enforceability: California Probate Code § 21311
  Many wills contain threats to disinherit anyone who challenges them. This statute limits the power of those clauses. A beneficiary cannot be penalized for a contest if the court finds they had “probable cause” to file the lawsuit.
• Standing to Contest: California Probate Code § 48 (Interested Person)
  Not everyone can sue. To contest a will, you must qualify as an “interested person”—typically an heir who would inherit under intestate succession (if there were no will) or a beneficiary named in a prior valid will.
• Financial Elder Abuse Remedies: California Probate Code § 859 (Double Damages)
  Will contests often overlap with elder abuse claims. If the court finds that a person used undue influence, fraud, or bad faith to take assets (or change a will) to the detriment of the estate, they can be liable for twice the value of the property taken, plus attorney fees.