Thirdly, and most importantly as a matter of practice, victim fault might be taken into consideration via what is known as the doctrine of contributory negligence. This rule applies when both of the following two conditions are satisfied: (1) the injured person must have failed to take reasonable care for his or her own safely; and (2) the failure to take care must be causally linked to his or her injury. It is convenient to look at both of these points in a little bit more detail.
A failure to take care will be unreasonable when the victim took less care than the reasonable hypothetical person would have taken in the same position. Thus, an accident victim will usually be found to have taken insufficient care where he or she accepts a ride from a driver whom he or she knew (or ought to have known) was intoxicated, runs across the road without checking for oncoming traffic (especially if this happens at night-time where the victim is wearing dark clothes), or drives in excess of the speed limit.
However, a failure to take reasonable care that is causally unrelated to the victim’s loss is irrelevant. Suppose that an accident victim drives with defective brake lights. That is very likely to amount to a failure to take reasonable care. But if the victim is injured in a head-on collision, that failure will be irrelevant. The contributory negligence doctrine will not apply in this situation.
If the doctrine of contributory negligence applies, the usual result is that the amount of compensation payable will be partially reduced. How is the amount of the reduction determined? It works as follows. The courts compare the victim’s responsibility for the damage suffered and the guilty party’s responsibility as percentages. For example, a victim might be 40% responsible and a negligent driver 60% responsible (the percentages will always add up to 100%) for the loss. In this event, the victim will recover 60% of the value of his loss. How do the courts assign percentages of responsibility? This is done in a rough and ready way (although in some situations the courts need to take account of statutory guidelines that limit their discretion in this regard). Judges proceed based on common sense and drawing on their experience. One study regarding the way in which judges reduce damages on the basis of the contributory negligence doctrine is available here.