Capacity Litigation, Equitable Claims and Remedies, Estates Litigation, Executor Conflict
The Rule In Saunders v. Vautier: When Beneficiaries Can Force A Trust To End
July 16, 2026

If you are looking to challenge, as an example, your parent’s Will, you must understand the importance of “capacity” in estate litigation.
Legal capacity is not the same as intelligence, age, or general health. A person can be elderly, forgetful, or even diagnosed with a cognitive condition and still have legal capacity, as long as they understood the specific decision they were making at the specific moment they made it.
Capacity is also decision-specific and time-specific.
This means your parent may have had capacity to sign a birthday card but not capacity to execute a will on the same day. It also means capacity can fluctuate: a person with dementia may have a period of clarity in the morning but lack capacity by the afternoon.
The Courts in Ontario look at the following to determine the validity of a Will:
If your parent could not satisfy one or more of these elements at the time of signing, their will may be invalid.
Wills are not the only documents that can be challenged. Each type of document has its own capacity standard:
Power of Attorney for Property or Personal Care: Your parent must have understood the nature of the document, what authority they were granting, and to whom. Ontario’s Substitute Decisions Act, 1992 sets out the specific capacity requirements.
Transfer of Real Property: To transfer a home or other real estate, your parent must have understood the nature of the transaction, the property involved, and the consequences of the transfer.
Gifts: For a significant gift made during a person’s lifetime to be valid, the donor must have understood the nature and effect of what they were giving away.
Medical records are typically the backbone of a capacity challenge. Relevant records include:
Even if there is no formal diagnosis, clinical notes describing confusion, disorientation, memory loss, or inability to recognize family members can be highly persuasive.
In Ontario, a lawyer who prepares a will or other legal document has a professional obligation to assess the client’s capacity before proceeding. Courts will look closely at:
People who spent time with your parent around the time of signing can provide critical evidence:
Courts are aware that family testimony can be self-interested, but corroborated accounts from multiple independent witnesses carry significant weight.
Sometimes the document contains internal clues that suggest capacity was compromised:
In most contested capacity cases, both sides will retain expert witnesses. A geriatric psychiatrist or certified capacity assessor can review all available records and provide an expert opinion on whether your parent likely had capacity at the relevant time.
Contact us at 416.901.9984 or info@pintoshekib.ca for a confidential consultation.