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Feb 26, 2026

Can A Spouse With Dementia Decide To Divorce?

by Steve Benmor

After getting married in 1979, Marie Louise Calvert started showing signs of cognitive decline in 1993. She was diagnosed and found to be suffering from the early stages of Alzheimer’s disease.  She was represented by a litigation guardian (her daughter from a previous marriage) and sought a divorce, equalization of net family property, and support from Ashton Calvert, who was a widower when they met.

By all accounts, Marie had a lovely personality. She was bubbly, active, socially gracious, and took great pride in her appearance. She loved to cook, go to movies, and go shopping. She adored children.

Marie and Ashton dated for two years, moved in together for a time and then eventually married on June 21, 1979. They signed a Marriage Contract. In 1988, Ashton sold the farm for $37.5 million. The Calverts' lifestyle, however, did not change. Ashton insisted that they live frugally.

Laura, as Marie’s litigation guardian, was pressing for a divorce, support and property division from Ashton. Ashton argued that Marie lacked the mental capacity to form the intention to separate and divorce, and therefore could not claim a divorce, support or equalization from him. Alternatively, he argued that the Marriage Contract barred her equalization claim. This case went to trial.

At trial, Laura testified that within four years of the marriage, Marie complained to her about her marriage. She said that her mother started to change in 1993. Laura gave very detailed evidence about the changes in her mother’s behaviour. She said that her mother began to be forgetful. She would ask several times what was for lunch. She was disorganized. She began to look dishevelled. She could not follow a conversation. She got confused with her cards playing Euchre. She would even forget to add bananas when baking banana bread.

In the end, the court found that Marie had the capacity to separate and divorce. The trial judge granted the divorce and held that the Marriage Contract did not bar equalization. Ashton was ordered to pay a substantial equalization payment of over $6M.

Some of the key legal principles and holdings from this case are:

  • Mental capacity is case-specific and based on the evidence.
  • Separation requires the lowest level of capacity.
  • Divorce requires only a slightly higher level.
  • The mental capacity required for divorce is lower than the capacity required to marry.
  • A litigation guardian may pursue a divorce on behalf of a person under a disability.
  • A judge will consider and determine allegations that the litigation guardian is acting improperly.

The case of Re Calvert (Litigation Guardian of) v. Calvert (1997), 32 O.R. (3d) 281 (Ont. Gen. Div.) is a leading Ontario authority on the low-capacity threshold for separation and divorce, the distinction between personal decision-making capacity and financial/legal capacity and the judicial protection of autonomy and dignity for individuals with cognitive impairments.

 

Steve Benmor, B.Sc., LL.B., LL.M. (Family Law), C.S., Cert.F.Med., C.Arb., FDRP PC, is the founder and principal lawyer of Benmor Family Law Group, a boutique matrimonial law firm in downtown Toronto. He is a Certified Specialist in Family Law, a Certified Specialist in Parenting Coordination and was admitted as a Fellow to the prestigious International Academy of Family Lawyers. Steve is regularly retained as a Divorce Mediator/Arbitrator and Parenting Coordinator. Steve uses his 30 years of in-depth knowledge of family law, court-room experience and expert problem-solving skills in Divorce Mediation/Arbitration to help spouses reach fair, fast and cooperative divorce settlements without the financial losses, emotional costs and lengthy delays from divorce court.