Overseas Tankship (UK) Ltd v Morts Dock and Engineering Co Ltd, commonly known as Wagon Mound (No. 1), is a landmark tort law case, which imposed a remoteness rule for causation in negligence. The Privy Council held that a party can be held liable only for loss that was reasonably foreseeable. Contributory negligence on the part of the dock owners was also relevant in the decision, and was essential to the outcome, although not central to this case's legal significance.
The Wagon Mound (No 1) should not be confused with the successor case of the Overseas Tankship v Miller Steamship or "Wagon Mound (No 2)", which concerned the standard of the reasonable man in breach of the duty of care.
Facts
Overseas Tankship had a ship, the Wagon Mound, docked in Sydney Harbour in October 1951. The crew had carelessly allowed furnace oil (also referred to as Bunker oil) to leak from their ship. The oil drifted under a wharf thickly coating the water and the shore where other ships were being repaired. Hot metal produced by welders using oxyacetylene torches on the respondent's timber wharf (Mort's Dock) at Sheerlegs Wharf fell on floating cotton waste which ignited the oil on the water. The wharf and ships moored there sustained substantial fire damage. In an action by Mort's Dock for damages for negligence it was found as a fact that the defendants did not know and could not reasonably have been expected to know that the oil was capable of being set alight when spread on water. The dock owners knew the oil was there, and continued to use welders.
The leading case on proximate cause was Re Polemis, which held that a defendant can be deemed liable for all consequences flowing from his negligent conduct regardless of how unforeseeable such consequences are. As this case was binding in Australia, its rule was followed by the New South Wales Court of Appeal. The defendant appealed to the Privy Council.
Judgment
The Privy Council found in favour of the defendant, agreeing with the expert witness who provided evidence that the defendant, in spite of the furnace oil being innately flammable, could not reasonably expect it to burn on water. The Board indicated Morts would probably have been successful if they had claimed damages for direct damage by the oil to the slipway but this was minor and not part of the damages claimed (although success on this count may have saved Morts Dock and Engineering the costs of all the litigation for both parties across all three levels of court). Viscount Simonds, in his delivery for the Privy Council, said that the Counsel for Morts had discredited their own position by arguing that it couldn't have been bunkering oil because it wouldn't burn on water. The Privy Council's advice soundly disapproved the rule established in Re Polemis, as being "out of the current of contemporary thought" and held that to find a party liable for negligence the damage must be reasonably foreseeable. The council found that even though the crew were careless and breached their duty of care, the resulting extensive damage by fire was not foreseeable by a reasonable person, although the minor damage of oil on metal on the slipway would have been foreseeable.
Viscount Simonds delivered the judgment of the Board and said:
It is, no doubt, proper when considering tortious liability for negligence to analyse its elements and to say that the plaintiff must prove a duty owed to him by the defendant, a breach of that duty by the defendant, and consequent damage. But there can be no liability until the damage has been done. It is not the act but the consequences on which tortious liability is founded. ... Who knows or can be assumed to know all the processes of nature? But if it would be wrong that a man should be held liable for damage unpredictable by a reasonable man because it was "direct" or "natural," equally it would be wrong that he should escape liability, however "indirect" the damage, if he foresaw or could reasonably foresee the intervening events which led to its being done.
It is a principle of civil liability, subject only to qualifications which have no present relevance, that a man must be considered to be responsible for the probable consequences of his act. To demand more of him is too harsh a rule, to demand less is to ignore that civilised order requires the observance of a minimum standard of behaviour.