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My mother was suffering from Alzheimer’s disease when she died. My sister tells me that Mother executed a new will two weeks before she died and appointed my sister as the estate trustee and sole beneficiary. How can that will be valid?

A Will can be set aside on the basis that the person lacked testamentary capacity to make a Will. Since this lady suffered from Alzheimer’s and this disease is generally known to impact an individual’s cognitive ability, one may presume that the Will may not be valid, since it was prepared while she suffered from cognitive impairment. However, testamentary capacity is not purely a medical question: it is also a legal question. Evidence would need to be gathered from various sources to assess whether the Mother’s cognitive impairment satisfied the legal test. If she did not have a sound and disposing mind within the rules at law, the Will could be set aside. The simple fact that a person has dementia may not be sufficient to set aside the Will.

If the Mother used a lawyer to prepare the will, the lawyer may be required to release his or her notes and to give evidence about the inquiries the lawyer made to assess the client’s ability to give instructions and to execute a Will. Doctors and other care providers can also be ordered to release medical and clinical notes, capacity assessments, and reports. Other individuals who regularly dealt with the Mother at the time the Will was completed may also have relevant information and may be asked to give evidence.   

A judge ultimately has to determine based on all the evidence if the Mother had a sound and disposing mind and was able to fully appreciate the nature and extent of her assets, her obligations to family, and the consequences of her decision.

Capacity to make a Will is task- and time-specific. A person may suffer from delusions but complete a valid Will during a lucid interval. Each case depends on its facts.

© 2015 Lawrence, Lawrence, Stevenson LLP

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