Unfortunately, though, the Canadian Supremes have put more bullets in the plaintiffs' guns than the defense's. First is as follows. The claim was for fibromyalgia and chronic fatigue syndrome which are, basically, bullshit. Chronic pain is real. Chronic fatigue is real. That is, both are symptoms of genuine pathologies. But fibromyalgia and chronic fatigue syndrome are as real as railway spine. (Shocking note: I tried to Google some skeptical sites on FMS and CFS and couldn't find anything. The Web really is a home for altie bullshit.) There is no single pathological process you can point to an label fibromyalgia or chronic fatigue syndrome. The idea that one can claim damages for being denied benefits for these "diseases" is disturbing.
Ordinarily, to call something a "disease", we need a process that is, in some way, deviant from the body's "normal" processes. Simple enough: things like colds pass this definition, as do things like cancer. (Injuries may as well; but, since I'm not trying to rule out injuries, this doesn't bother me.) So, the question is: what "process" underlies FMS or CFS? If one can be found, then it's not FMS or CFS! For example, fatigue is often a symptom of hypoglycemia. The deviant process that is hypoglycemia can be found; and, since it can be found, the patient would be diagnosed with hypoglycemia, not CFS. The same holds for FMS.
Secondly, plaintiffs can now dump in a "mental distress" claim if their benefits are denied. Which is insane. While it might be "distressing" to be denied benefits, I cannot for the life of me see how (1) this can be a pathology for which one deserves compensation and (2) how it's the insurance company's problem that, basically, you're a wuss.
Insurance companies' purpose is not to pay you what you "deserve". They enter into a contract with a consumer to provide a certain level of payment if certain conditions are met. For example, life insurance pays out if the consumer dies. So, unless the insurance contract is very badly worded, I'd think that disability insurance will only pay out if one has an actual pathology which disables one (usually from working). "Mental distress" due to denial of benefits is hardly enough to disable one, unless one is exceptionally fragile -- in which case, surely one would not have been insurable. (Interesting side-note: if you turn out to be a fragile sort of person who can't handle being denied benefits, are you as liable to have your insurance cancelled as someone who, even unknowingly, concealed osteoporosis and then suffered a fracture partially due to the underlying condition?) So, to allow claims for mental distress exposes insurance companies in an unacceptable way, and may (I would think) lead to a refusal to cover any mental illnesses.