Undue Influence or Lack of Capacity: Which Theory Fits Your Facts?

[author: Natalie Ortiz]*

In California estate and trust litigation, attorneys often face a choice and must carefully evaluate whether to assert undue influence, lack of capacity, or both, depending on the facts and available evidence. Here are some thoughts on how they make that decision and what factors they consider.

Please note, the information here is intended to be directional and address the issues in general terms. Any decision an attorney makes will depend—first and foremost—on the facts of a specific case and how those facts will be viewed and applied by a judge.

HOW ARE THE TWO CLAIMS DIFFERENT?

LACK OF CAPACITY

• Focus: Determining an individual’s capacity requires examination of the mental state of the testator, that is, the person who made the will or trust.
• Legal Standard: A testator with adequate mental capacity will understand the nature of the testamentary act, the extent and character of their property, and their relationships to beneficiaries.
• Evidence Required: Medical records or expert testimony showing cognitive impairment at the time of execution, and witness testimony about confusion, memory loss, or irrational behavior.
• Challenges: California law presumes capacity, although that presumption is rebuttable and subject to specific legal standards depending on the type of decision or document involved. Even individuals with delusions or eccentric behavior may be deemed to have capacity if lucid during execution.

UNDUE INFLUENCE

• Focus: Determining the existence of undue influence calls for an assessment of the actions of a third-party bad actor who manipulated the testator.
• Legal Standard: A party claiming undue influence must prove that the testator was vulnerable, the influencer had apparent authority or control, and that the influencer used tactics like isolation, dependency, or manipulation.
• Evidence Required: Proof of coercion, isolation, or control over the testator’s decisions, and testimony about changes in behavior or relationships.
• Advantages: Undue influence, generally speaking, may be easier to prove than lack of capacity. It does not require full incapacity—only vulnerability.

STRATEGIC CONSIDERATIONS FOR ATTORNEYS

Attorneys will assess these factors when deciding which claim to pursue:

1. Type and Timing of Evidence. A) Medical documentation showing dementia or cognitive decline may support lack of capacity and B) behavioral evidence (e.g., isolation, dependency, sudden changes in estate plans) may support undue influence.
2. Strength of Presumptions. Capacity is strongly presumed (although rebuttable) under California law. Undue influence may shift the burden of proof if a confidential relationship is shown.
3. Nature of the Relationship. If the influencer was a caregiver, family member, or someone in a position of trust, undue influence may be a more viable approach.
4. Document Execution Circumstances. Was the will or trust executed in private, without independent counsel? Were there sudden or unexplained changes in beneficiaries?
5. Cost and Complexity. Both claims require expert testimony and can be expensive. Attorneys may choose the path with the most compelling and cost-effective evidence.

Often, both claims are asserted together. However, attorneys may emphasize one over the other depending on: A) the availability of medical records; B) witness credibility; C) the presence of a manipulative third party; and D) the likelihood of shifting the burden of proof.

MAKING THE CHOICE

If, when an attorney examines the facts of the case:

1. There is strong medical evidence of cognitive impairment, the attorney will lean toward asserting lack of capacity.
2. There is behavioral evidence of manipulation or control, the attorney will assess whether a confidential or dependent relationship existed. This would support an undue influence claim.
3. There is evidence of both types, the attorney may decide asserting both claims would be the better strategy.

Other factors are put into the mix, such as whether the execution circumstances (e.g., lack of independent counsel) and relationship dynamics allow for a burden shift, and the relative viability of a claim in light of the evidence and cost-effectiveness.

Choosing between an undue influence claim and a lack of capacity theory in California estate and trust litigation depends on a careful evaluation of the specific facts, available evidence, and strategic considerations unique to each case in order to determine the relative viability and cost-effectiveness of a claim. Each approach presents its own challenges and advantages, and often, both may be asserted to strengthen a legal position. If a dispute arises over the validity of a will or trust, it is crucial to consult with an experienced probate litigator who can evaluate the circumstances and guide you through the complexities of the law to protect your interests.

*Senior Litigation Attorney with The Estate Lawyers, APC, in our San Diego office.