The decision in Najafi v. Shapiro provides a teachable moment. The decision implies that the precondition for the application of section 5 of the Limitations Act is the plaintiff raising discoverability:
[35] The moving defendants rely upon Section 4 and Section 5 of the Limitations Act, 2002 as the substantive law for the limitation defence they ask the court to apply to dismiss the 2015 action as against them. Section 4 of the Limitations Act, 2002, reads as follows […]
[36] On facts where discoverability is raised as an issue, Section 5 is applicable […]
This is wrong. There’s no precondition to the application of section 5, which is a necessary part of a limitations analysis. Section 4 links the commencement of the basic limitation period to the discovery of a claim. Section 5 provides when discovery of a claim occurs. Accordingly, it’s impossible to determine when a limitation period commences without applying section 5.
Here’s the language of section 4 and 5(1)-(2):
Basic limitation period
4. Unless this Act provides otherwise, a proceeding shall not be commenced in respect of a claim after the second anniversary of the day on which the claim was discovered. 2002, c. 24, Sched. B, s. 4.
Discovery
5. (1) A claim is discovered on the earlier of,
(a) the day on which the person with the claim first knew,
(i) that the injury, loss or damage had occurred,
(ii) that the injury, loss or damage was caused by or contributed to by an act or omission,
(iii) that the act or omission was that of the person against whom the claim is made, and
(iv) that, having regard to the nature of the injury, loss or damage, a proceeding would be an appropriate means to seek to remedy it; and
(b) the day on which a reasonable person with the abilities and in the circumstances of the person with the claim first ought to have known of the matters referred to in clause (a). 2002, c. 24, Sched. B, s. 5 (1).
Presumption
(2) A person with a claim shall be presumed to have known of the matters referred to in clause (1) (a) on the day the act or omission on which the claim is based took place, unless the contrary is proved. 2002, c. 24, Sched. B, s. 5 (2).