I would not go as far as saying that the court has created a direction specific to MAID that states that a legislative approach, when it comes to mental disorder or any other condition, must be on a case-by-case basis.
However, the section 15 jurisprudence recognizes that forms of treatment on an enumerated ground that are strictly categorical—for instance, all members of a particular group must be treated in this way because they have this characteristic or are at risk for particular vulnerabilities—may not pass constitutional muster.
To go back to my comments about the Oakes test and when a violation of section 15 (1) can be justified, there have been many cases that have recognized that a minimally impairing alternative—an alternative to saying that one group has to be treated in this particular fashion—is individualized or case-by-case assessment.