The concept of ‘causation’ is what a plaintiff must prove. Not only that they suffered damages/injuries, but more specifically that those damages/injuries were caused by the defendant. In most cases ‘causation’ will appear obvious, but in many cases it is not as clear. For example, what if the plaintiff had suffered from similar complaints before the accident? There are principles to be applied to help.
The Supreme Court of Canada in Athey v. Leonati,  3 S.C.R. 458, gave the principles to be applied for causation in personal injuries cases. Those principles include:=
- a. An inference (deduction) of causation may be drawn from the evidence without positive scientific proof.
- b. Causation need not be proved with scientific precision, and the causation test should not be applied too rigidly. It is “essentially a practical question of fact which can best be answered by ordinary common sense.
- c. The plaintiff must prove that the injury would not have occurred but for the defendant’s negligent accident.
- d. A second formulation of this principle is that the plaintiff must prove that the defendant’s negligence materially contributed to the occurrence of the injury.
It will be important for your lawyer to be aware of these concepts and be prepared to argue them with the defendant’s representatives. You need to ensure that your lawyer is aware of your complete medical history so that any past issues can be dealt with and distinguished as possible ‘causes’ of your current complaints.