In every civil case, the plaintiff has the burden of proving the basic elements of negligence—duty, breach, causation and damages—and such proof is required by “a preponderance of the evidence”. This is defined as “more probable than not” or “more likely true than not true” or “on a 51% basis”. The reality is that a plaintiff must be prepared to show proof on a much more significant basis than 51%, as a juror is unlikely to award significant damages without substantial proof of injury and loss.
However, there are some cases that impose a different burden on a plaintiff—notably Products Liability cases in the US are governed by Strict Liability. In such cases, a plaintiff who was injured by a defective product must prove that the product was defective. Once the product is shown to have been manufactured defectively, the defendant manufacturer is liable, period. If, for example, a family is driving down the road and one of the tires on the vehicle suffers a sudden loss of air or “blowout”. The vehicle flips, passengers are ejected and all suffer serious personal injuries and losses. At trial, the injured parties must prove that the blown out tire was manufactured defectively, and once proven, their burden stops there. The manufacturer of the defective tire is then liable for any damages that are proven.
In BC, a plaintiff’s burden of proof for a defective products case is much more onerous. There a plaintiff must prove that the defendant manufacturer was negligent in the way it designed or manufactured the product. This is a significant burden and good reason why there are very few products cases that proceed to judgment in British Columbia.