Why are some close family members of citizens or permanent residents exempt from the excessive demand rule?

Parliament decided that certain close family relationships should not be broken up over the cost of anticipated health or social services, so specific categories of family class applicants are excluded from the excessive demand assessment entirely, even if their medical condition would otherwise meet the test. This reflects a policy choice that family unity, for these specific relationships, matters more than the potential cost to public services.

The exemption is narrow and depends on exactly which family class category someone falls into — it is not a blanket exemption for "family members" in general, and other grounds of medical inadmissibility, such as being a danger to public health or safety, still apply even where the excessive demand exemption does. People sometimes assume that because they are being sponsored by close family, cost-based medical inadmissibility can never apply to them, which isn't quite right — it depends on the specific sponsorship category and relationship.

Because eligibility for this exemption depends on precise categorization, anyone relying on it should confirm their specific relationship and application stream actually qualifies, rather than assuming family sponsorship in general is automatically covered.