Tort Law - Negligence
It is necessary for a negligence case to succeed that the harm should reasonably be foreseeable as a result of the act or omission at the centre of the claim. A duty of care exists in relation to preventing a given risk, as long as the risk is reasonably foreseeable. The standard applied by courts in determining foreseeability is whether a reasonable person in the position of the defendant should have foreseen it.
Unfortunately the reasonable person has proven to be a somewhat more lucid and thoughtful individual than one might at first think. A person of truly normal competence and tendencies in foreseeing risks would rarely come up to the standard expected by courts. (It is the author’s opinion that such foresight comes only as an advanced skill to be learned over years). Although courts are acutely aware of the deceptive nature of hindsight and regularly try to avoid thinking of the actual events of a case as being patently obvious, the reasonable person is taken by the common law now as being an individual possessed of a formidable talent for anticipating contingencies. What is even more interesting also, is the extraordinary impracticality imputed to the reasonable person when the question of contributory negligence arises in defence.
A leading case on foreseeability was Wyong Shire Council v Shirt. A waterskiing club built a jetty in a lake and the Wyong Council dredged a channel from the jetty to the deeper water in the middle of the lake. Signs were erected along the channel warning of deep water. The plaintiff mistook the signs as meaning that the whole lake was deep and skied in the shallows. He came off the skis in water one metre deep and hit his head on the bottom, becoming quadriplegic. The plaintiff sued various parties involved in the matter.
The court reasoned that a risk which is not far-fetched and fanciful is real, and therefore foreseeable. One must consider the magnitude of the risk and the probability of the risk together to judge its foreseeability. In this case, the court ruled, due to the ambiguity of the signage, a reasonable man might well have read them wrongly and mistaken the position of the deep water. He might also consider the risk that would be borne by a skier in water only one metre deep.
Some persons have special vulnerabilities such as sight impairment, a lame foot, old age and so forth, and as a result may be far more likely than most to come to harm. While commonsense may require such people to take extra care for themselves, the law does not require this. As long as a certain form of vulnerability is reasonably common, anyone whose negligent act or omission results in harm to them is liable in the same manner. An example is Haley v London Electricity Board where a blind man walking alone walked through inadequate barricades on a footpath and fell into a ditch. This resulted in brain damage that caused the loss of his hearing. Due to the commonness of blindness, it was reasonable that the responsible workers should have foreseen the potential for such a person to walk up and miss the barricades.
Purely Mental Harm
When dealing with a claim for pure (or primary) mental harm, the foreseeability of the harm claimed for depends on what would be suffered by a person of normal fortitude. This rule applies where the mental harm is resultant directly from the defendant’s negligence, and not from the plaintiff’s suffering of a physical injury caused by the defendant. Secondary mental harm, unlike primary mental harm, is still claimable per se.
In the dual appeal session of Tame v New South Wales; Annetts v Australian Stations Pty Limited, Ms Tame experienced mental harm resulting from an incorrectly recorded BAC after her involvement in a collision. Being worried for her reputation as a teetotaller, she became clinically depressed. The High Court ruled that the mental harm experienced was not reasonably foreseeable and Ms Tame was not of normal fortitude. An interesting aside in that judgment was put by Gaudron J, that if the defendant has particular knowledge of the plaintiff’s special vulnerability or of factors about the plaintiff which make them vulnerable, then liability still stands. The court was quite clear also in this case that a person merely bearing bad news has no duty of care as to the mental wellbeing of the recipient.
 Wyong Shire Council v Shirt (1980) 146 CLR 40.
 Haley v London Electricity Board  AC 778.
 Tame v New South Wales; Annetts v Australian Stations Pty Limited  HCA 35.