Dear Colleagues,

When teaching the Supreme Court of Canada's decision in Mustapha v. Culligan, it was previously my view that the decision did not purport to broadly change the "thin skull" rule, but that it added an additional threshold question of foreseeability in the case of mental injury (would a "person of ordinary fortitude" suffer such injury). However, some push back from a student and some additional reading of cases (e.g. Greenway-Brown v. MacKenzie, 2019 BCCA 137 (CanLII), <https://canlii.ca/t/hzxbk>) has undermined this view, while at the same time somewhat reinforcing it. For example, in Greenway-Brown, the BCCA put it this way:

[93]        It is my view that the judge erred in applying this principle from Mustapha in the circumstances of this case. While I agree with the respondents that the same duty of care and foreseeability analysis applies to claims in negligence for both mental and physical injury, Mustapha is concerned with mental injury; more particularly, what mental injury is sufficient to constitute damage (as discussed above), and what mental injury is foreseeable to establish legal causation.

While re-reading Mustapha does suggest to me that the SCC was indeed speaking broadly (capturing both physical and mental injury), it strikes me that this was a very understated way for modifying a fairly strong and clear precedent, and that the "ordinary fortitude" standard is potentially a quite significant constraint and bolsters remoteness as a "controlling device" for limiting liability.

Any insights from members of this group who write in this area (e.g. remoteness) would be greatly appreciated.

Best,