• In the case of McKew v Holland & Hannen [1969] 3 All E.R. 1621, it was held that where an injured person suffers further injury from their own unreasonable conduct, it breaks the chain of causation stemming from the other party regarding the further injury, even if they were liable for that person’s initial injury.

Facts of the Case

  • C suffered trivial injuries during employment which were admittedly caused by fault of their employer, D. Their back and hips were strained, preventing them from bending, and their left leg would occasionally ‘went away from them.’ Estimated time of recovery was one or two weeks.
  • Ten days later, C inspected a first-floor flat for which they were offered a tenancy. They were accompanied by their wife, child and brother-in-law. The flat was approached by a steep stair between 2 walls with no handrail.
  • On leaving the flat C’s wife and brother-in-law secured the door while C descended the stairs with their child. As they did, their left leg gave away and he pushed their child away. To prevent themselves from falling headfirst C jumped some ten steps.
  • In landing C suffered a severe ankle fracture. C alleged that D were liable for this latter injury.


  • Was D liable for an injury that would not have occurred if C had not suffered the initial injury, which D was admittedly liable for?

Held by the House of Lords (Scotland)

  • Finding for D, held that C attempting to descend steep stairs with no handrail without adult assistance was in the circumstances (or alternatively jumping the stairs) was unreasonable. As such, the chain of causation between D and the fracture was broken and D could not be held liable for the latter injury.

Lord Reid

  • A man injured in such a way that his leg may give way at any moment, he must act reasonably and carefully. However, he cannot hold anyone liable for further injuries caused by his own unreasonable conduct. His unreasonable conduct is an intervening act. Alternatively, that unreasonable conduct and what follows is not the natural and probable result of the original fault of D or of the ensuing disability.
  • Foreseeability does not come into this. A defender is not liable for an unforeseeable consequence. But he is not necessarily liable for every consequence which is reasonably foreseeable. It is often easy to foresee unreasonable conduct or another intervening act as being likely, but it nevertheless breaks the chain of causation.
  • C must have known that the only safe way to descend the stairs was slowly and carefully so he could sit down if his leg gave out, or with adult assistance.
  • “But I think it right to say a word about the argument that the fact that the appellant made to jump when he felt himself falling is conclusive against him. When his leg gave way, the appellant was in a very difficult situation. He had to decide what to do in a fraction of a second. He may have come to a wrong decision: he probably did. But, if the chain of causation had not been broken before this by his putting himself in a position where he might be confronted with such an emergency, I do not think that he would put himself out of court by acting wrongly in the emergency unless his action was so utterly unreasonable that even on the spur of the moment no ordinary man would have been so foolish as to do what he did. In an emergency it is natural to try to do something to save oneself and I do not think that his trying to jump in this emergency was so wrong that it could be said to be more than an error of judgment. But for the reasons already given I would dismiss this appeal” [26].