An involuntary commitment under the Mental Health Code can only be done for someone who suffers from a mental illness. The definition of mental illness in Chapter 571 of the Code specifically excludes "senility" from the definition. But it does not define senility.

My question is whether or not an involuntary commitment can be done if the diagnosis in the certificate of medical examination is dementia or alzheimers. In other words, are dementia/alzheimers considered to be mental illnesses or are they considered to be senility?

Alzheimer's is a type of dementia, for which the statutory category is "senility". That having been said, ask the applicant to refile, identifying behaviors that the person is exhibiting which would require treatment. For example, if the person is wandering at night, they are placing themselves in jeopardy both by exposure and the likelihood of being hit by a vehicle. Or, if the person believes their food is poisoned, they are placing themselves at risk from serious harm by limiting nutritional requirements. Both of the foregoing meet the dangerousness to self standard.

Finally, asking the examiners to rely upon a "Psychosis NOS secondary to a medical condition (i.e. Alzheimer's syndrome)" would meet the diagnostic standard for a "mental illness."

As well, the deterioration standard can be relied upon - though getting an OPC on such a standard requires creative pleadings. This may also mean woodshedding the examiners who are often unaware of the technicalities of applicants - as well as testimony.