causation Flashcards
Factual causation: the ‘but for’ test
The ‘but for’ test: on the balance of probabilities, but for the defendant’s breach of duty, would the claimant have suffered their loss at that time and in that way?
If no, factual causation is satisfied. The claimant would not have suffered their loss were it not for the defendant’s breach.
If yes, factual causation is not satisfied, and the defendant is not liable. The claimant would have suffered their loss even without the defendant’s breach.
Factual causation in clinical negligence where breach is a failure to advise on risks
Chester v Afshar [2004] UKHL 41-
The surgeon failed to disclose to the claimant the very small risk of paralysis resulting from surgery. After the operation, the claimant suffered paralysis in one leg.
The defendant argued that causation could only be proved if the claimant could show that she would not have had the operation had she been warned of the risk. The court took a more relaxed approach: where the breach is a failure to advise on risk, the ‘but for’ test is satisfied if the claimant can prove on the balance of probabilities, that if they had been warned of the risk, they would not have had the operation or deferred it to a later date. The claimant proved that ‘but for’ the surgeon’s failure to warn, the injury would not have occurred when it did and the chance of it occurring on a subsequent occasion (if the claimant had the operation later) was very small.
where factual causation exists but the test can’t be satisfied - Material contribution test (cumulative causes)
standard = more than negligable
this is when there is more than one cause of the claimant’s loss, and the causes were acting together (cumulatively) to cause the loss.
e.g. if the defendant’s breach could be proved to have materially contributed to the claimant developing the disease, then the defendant would be liable for all the loss. By material contribution, the court meant a ‘more than negligible’ contribution to the loss.
Case law has confirmed that the material contribution test applies to sequential cumulative causes (ie where one cause comes after the other: for example, say the claimant has a fall and suffers a head injury, then later receives negligent medical treatment and the medical evidence is that the fall and the clinical negligence have caused brain damage) as well as to simultaneous cumulative causes (ie causes operating at the same time: in Bailey the negligent treatment and underlying medical problems caused the weakness simultaneously).
where factual causation exists but the test can’t be satisfied - material increase in risk test
Standard = the contribution to the risk must be greater than de minimus
This is easier to satisfy than the material contribution test as the claimant does not even have to prove that the breach made any actual contribution to their loss, just that it increased the chances of the claimant suffering that loss.
Applicable only to industrial disease, single agency cases e.g. dust.
where factual causation exists but the test can’t be satisfied - loss of chance
In Hotson v East Berkshire Health Authority [1987] a child fell from a tree and broke his leg. The hospital was negligent in its treatment and the child was left paralysed. However, medical evidence indicated that there was a 75% risk that the broken leg would have left the claimant paralysed even without the negligent treatment. The ‘but for’ test therefore failed.
Instead, the claimant argued ‘loss of chance’ ie that he had lost a 25% chance of recovery due to the defendant’s negligence and should be awarded 25% of his losses. The House of Lords rejected this argument. The reality of the situation was that the child was most likely paralysed by the original fall.
Although the ‘loss of chance’ argument does not seem to apply to medical negligence or personal injury cases, the courts have allowed the test in cases involving pure economic loss. In Allied Maples Group v Simmons & Simmons [1995] 1 WLR 1602 (CA), the claimant lost the chance to negotiate a clause in a contract as a result of the solicitor’s failure to advise. Causation was successful as the claimant proved that there was a real and substantial chance that the seller would have agreed to the clause.
Apportionment
Apportionment is a calculation to apply once factual causation has been established. Where there are multiple tortious factors which are known to have caused part of the loss, the courts apportion liability between the defendants in a way that produces a practical result, providing compensation to the claimant while recognising the respective fault of the defendants.
Key case: Fitzgerald v Lane & Patel [1987] QB 781:
The claimant crossed the road at a pelican crossing when the lights were red for pedestrians. The first defendant driver collided with him and the claimant was thrown from the bonnet of that car into the road, where he was run over by a car driven by the second defendant.Both defendants had been negligent, and the claimant was equally at fault. It was impossible to say which of the two collisions had actually caused the injuries, or to what extent each had contributed.
Held: each defendant was responsible for 25% of the claimant’s losses (50% of the claimant’s losses were not recoverable, representing the claimant’s own negligence). End of key case.
Multiple sufficient causes
In cases such as Bonnington, the claimant suffered one loss. What happens where the claimant suffers damage as a result of the defendant’s negligence and then, some time later, a second event occurs which causes exactly the same damage, or worsens the damage already caused? In these situations, the events are not linked and there are two or more distinct losses that can be attributable to distinct causes. There is more than one defendant each of whom pass the ‘but for’ test, but one action comes after the other (or if the later action is non-tortious, it has caused the subsequent harm). Is the original tortfeasor responsible for the loss caused by the other?
Key case: Performance Cars v Abraham [1962] 1 QB 33: a third party negligently collided with the claimant’s Rolls Royce. The Rolls required a respray to remedy it. Two weeks later, a second collision between the same Rolls Royce and a different car, driven by the defendant, caused similar damage which also required a respray to repair it.
Held: as the requirement for a respray already existed before the second collision, there was effectively no damage arising from the second collision.
Apportionment and multiple sufficient causes - summary
Where multiple tortious factors have caused the loss, the courts apportion liability between the defendants to produce a practical result, providing compensation to the claimant while recognising the respective fault of the defendants.
* Where there is more than one defendant, each of whom passes the ‘but for’ test for distinct separate losses, but one of their actions comes after the other, consider multiple sufficient causes. The later action may be non-tortious eg a natural event, but is the factual cause of the later loss.
* If the second defendant has not caused any additional damage to the claimant, they will not be liable.
* If the second event is tortious, the first defendant is liable for the original damage past the point of the second event. The second defendant is liable for any additional damage.
* If the second event is naturally occurring, the defendant is liable for damage only up to the natural event.
legal causation
Factual causation deals with establishing the link between the breach and the damage, whereas legal causation involves considering whether there are any grounds upon which the link should be regarded as having been broken.
Once factual causation has been established, it is then necessary to see whether, as a matter of law, the defendant may be held liable. The defendant is not liable for absolutely everything that follows from their breach. A line has to be drawn and certain subsequent events that occur after the breach may break the chain of causation. This is the principle of novus actus interveniens ie an intervening act. Whether a subsequent event breaks the chain or not will depend on the nature of what occurs.
legal causation acts of god/natural events
An act of God breaks the chain of causation if it is some exceptional natural event. Natural events can include, for example, being struck by lightning, drowning in a flood, or the onset of disease.
Natural events will not break the chain of causation if they could have been foreseen and the defendant should have taken them into account as events that were likely to happen.
legal causation - Acts of third parties
Where the subsequent event is the act of a third party, the courts have viewed it as breaking the chain of causation if it was highly unforeseeable (something that was very unlikely to happen as a result of the defendant’s negligence).
legal causation - Acts of third parties: medical treatment
When the act of third party is medical treatment, the courts are reluctant to hold that this breaks the chain of causation. When a defendant causes injury, they take the risk that the claimant may not respond well to medical treatment or that the treatment may not be perfect. The medical treatment will not break the chain unless it is so gross and egregious as to be unforeseeable.
legal causation - acts of the claimant
Sometimes, the courts will be required to consider whether the claimant’s own actions break the chain of causation (ie where the claimant does something which causes them further harm).
The legal test for an act of the claimant breaking the chain of causation is that the act must be highly unreasonable. It is rare for the claimant’s unreasonable behavior to break the chain of causation as this would normally be dealt with under the defence of contributory negligence. This produces a fairer result, whereby the defendant is still liable for the claimant’s loss, but the claimant’s damages are reduced to reflect the extent to which they contributed to their loss.
