It is becoming increasingly common to see mild cognitive impairment raised in capacity disputes. These cases often raise a difficult question: when does cognitive decline cross the threshold into legal incapacity?
MCI, or what is now clinically described as a mild neurocognitive disorder, reflects a decline in cognitive functioning that is greater than expected with normal aging. However, it does not follow that a diagnosis of MCI, on its own, results in a finding of incapacity. Capacity remains a legal determination, not a medical one.
Ontario courts have consistently emphasized that capacity does not require independence. In Koch (Re), the Court confirmed that an individual may remain capable even if they rely on others to assist in carrying out their decisions. The focus is on whether the person can understand the relevant information and appreciate the consequences of their decisions, not whether they can implement those decisions entirely on their own.
This principle is particularly important in the context of MCI. Individuals experiencing mild cognitive decline may require some degree of assistance in organizing information or executing decisions. They may rely on family members or trusted advisors for support. However, that reliance does not, in itself, undermine their ability to make decisions or establish incapacity.
Consistent with this approach, recent case law reflects a growing reluctance to impose guardianship where less restrictive options are available. In D.R. v. A.R., 2026 ONSC 796, the Court declined to appoint a guardian of property despite concerns about cognitive decline, noting that the individual’s needs could be addressed through existing or revised power of attorney arrangements.
More broadly, this reflects a shift in focus, with courts increasingly considering whether appropriate supports can be put in place to allow individuals to continue making their own decisions. While Ontario does not formally recognize a regime of “supported decision-making,” similar principles are reflected in the Court’s approach and there is a preference for solutions that respect independence and avoid removing decision-making authority.
At the same time, however, these cases remain highly fact specific. The presence of MCI may raise concerns about vulnerability, particularly in situations involving complex financial arrangements or potential undue influence. Courts must balance the goal of preserving autonomy with the need to protect individuals from harm. This requires a careful, contextual analysis of the individual’s actual decision-making ability.
Ultimately, the takeaway is that a diagnosis of MCI does not determine the outcome of a capacity analysis. The focus remains on whether the individual can understand and appreciate the decision at hand. Where that ability exists, even if it is exercised with assistance, courts may be reluctant to interfere.
Thank you for reading!
By Yalda Mostafaie