Essay: Causation

An essential element to establishing a claim of Negligence is that the breach of a duty of care by a Defendant caused loss suffered by a Claimant – or, there’s a causal connection between the Defendant’s carelessness and the Claimant’s loss.  The principles of causation ensure that the Defendant won’t be liable for damage he didn’t cause by his acts or omissions.
To establish causation, there has to be a clear link between the duty of care and breach of duty to the loss suffered by a Claimant.  It isn’t enough that following the breach of duty, the Claimant suffers loss.  The actions (or omissions) of the Defendant must have caused the loss [Barnett v Chelsea and Kensington Hospital Management Committee (1968) QB 1 All ER 1068].  If they did not, the claim will fail.
The ‘but for’ test is applied by the Courts to assist in identifying a causal link – ‘but for’ the actions of the Defendant, the injury or loss suffered by the Claimant would not have been sustained.  An example is in Cummings v Sir William Arrol & Co Ltd (1962) 1 WLR 295, where it was held that even if a safety belt had been provided to the deceased, he would not have worn it and therefore after applying the ‘but for’ test, he would have died anyway.
Causation is tied with remoteness because, the person will only be liable for the chain of events that follows which are reasonably foreseeable or “natural, necessary or probable consequences” which the reasonable man ought to have foreseen [Overseas Tankship UK Ltd v. Mort Docks and Engineering Co Ltd, The Wagon Mound No. 1 (1961) 1 All ER 404].  Lord Reid comments, “A defender isn’t liable for a consequence of a kind which isn’t foreseeable.  But it doesn’t follow that he is liable for every consequence which a reasonable man could foresee” [McKew v Holland and Hannen and Cubitts (Scotland) Limited (1969) HL 3 All ER 1621].  For the act of the Claimant or third party to break the chain, it supposedly should be entirely unreasonable in all circumstances.  Again, every case is assessed on its own facts.
In a Negligence claim, the burden of proof rests on the Claimant – i.e., it’s for the Claimant to prove that the Defendant’s negligence materially contributed to t Wilsher v Essex Area Health Authority (1988) HL 1 All ER 871, it’s for the Claimant to show that the Defendant’s actions or omissions are the likely cause of the loss.
An important aspect of proving causation is that the chain of events between the actions or omissions of the Defendant and the loss suffered by the Claimant must not be broken.
Lord Wright describes a break in the chain as “something that is extraneous or extrinsic”, that is, an external event having no part of the original incident.  This may be an act of a third party – a nova actus interveniens, or an event occurring without the act of a third party – a nova causa interveniens.
For example, in Jobling v Associated Dairies Ltd (1981) 2 All ER 752, the Claimant injured his back at work causing his earning capacity to be reduced by 50%, but he subsequently contracted a disease.  This was a non-tortious intervening event (a nova causa interveniens) quite separate from the original injury, and would be what Lord Wright describes as “a new cause, which disturbs the sequence of events” [Lord v Pacific Steam Navigation Co Ltd, The Oropesa (1943) 1 All ER 211].  Consequently, it was held to break the chain of causation.
However, the act may not always break the chain.  In Baker v Willoughby (1969) 3 All ER 1528, the Claimant sustained injuries to his leg causing loss of earnings, pain and discomfort.  He was subsequently shot in the knee (a tortious intervening event) and the leg was amputated.  It was held that the supervening event did not obliterate the original injury, as the Claimant was no less lame or disabled.
The two cases, Baker v Willoughby and Jobling v Associated Dairies Ltd, appear to conflict but can be reconciled in that a tortious act won’t break the chain, whereas a non tortious act will.  In any event, each case is assessed on the facts and in light of policy.  It is hard to reconcile Jobling with Lord Wright’s comment in Lord v Pacific Steam Navigation Co Ltd, as being shot in the knee would appear to be ‘extraneous’ or ‘extrinsic’ to the original injury, and quite unforeseeable.
An intervening act by the Claimant can break the chain of causation.  In McKew v Holland and Hannen and Cubitts (Scotland) Limited (1969) HL 3 All ER 1621, the Claimant suffered injury by the Defendant to his leg, but then went on to do an act which was regarded as “an intervening act which broke the chain of causation”.  The Lords in this case held that the Claimant should have taken more care.  On reading the facts of the case, it’s again difficult to tie this in with Lord Wright’s comment in Lord v Pacific Steam Navigation Co Ltd, as the Claimant merely went up some steep stairs, and this is hardly an ‘unjustifiable’ ‘new sequence of events’.
In conclusion, I think Lord Wright’s comment sets out the law, as it should be.  A person should be liable for his actions, which he can reasonably foresee the consequences of and this is a principle of the rule of law.  Having committed a tort, he then should be liable for the consequences he has caused.  The doctrine of remoteness is in place to limit claims to a sensible amount, to make the tort of Negligence workable and to protect insurance companies and indeed, Defendants from not being liable for acts for which they have not caused.  Any external, remote and unforeseeable act, as Lord Wright says, breaks the chain of causation.  This is unfortunately not reflected in case law and the position appears unclear.  In Jobling v Associated Dairies Ltd for example, the chain of causation was broken by the Claimant’s subsequent disease.  The Defendant would have ‘got away’ with the original injuries sustained by the Claimant.  In Baker v Willoughby however, the Claimant is shot – a totally external, unforeseeable event that occurred at a later date.  The House of Lords decided they did want to impose a duty for the earlier injuries to the leg, despite the fact that the pain and suffering no longer existed, as there was no leg!  Further, in McKew v Holland and Hannen and Cubitts, the act done by the Claimant could be seen to be fairly trivial and yet was held to be an extrinsic event, breaking the chain of causation and there was no regard for liability for the original act as there was in Baker v Willoughby.