The Elements of Contributory Negligence
To establish contributory negligence, the defendant must demonstrate that: Davies v Swan Motor Co  2 KB 291
- The claimant did not take reasonable care for their safety or was otherwise at fault for their injury; and
- The claimant’s lack of care contributed to the occurrence of the damage or its extent.
This defence is not available for the personal interference torts: Pritchard v Co-Operative Group Ltd  QB 320.
What is Lack of Reasonable Care?
The case-law has established the following about the meaning of ‘fault’ and ‘lack of reasonable care’:
- An intentional act of the claimant, such as deliberate self-harm, can be characterised as ‘fault’: Corr v IBC Vehicles Pty Ltd  AC 884;
- Lack of reasonable care does not have to amount to a breach of a duty owed to the defendant: Davies v Swan Motor Co  2 KB 291;
- The claimant is not responsible for the damage if it was not foreseeable that their actions might be harmful to himself: Jones v Livox Quarries  2 QB 608;
- Children are held to the standard of reasonable children, meaning that they are less likely to be found to have taken inadequate care: Gough (an infant) v Thorns  1 WLR 1387.
Reasonable Care in Emergencies
If the defendant puts the claimant in a situation where he is at risk regardless of how he acts, the claimant’s response will normally be considered reasonable: Adams v Lancashire and Yorkshire Railway Co (1869) 4 LR CP 739.
Where the claimant is intervening to rescue other victims of the defendant’s negligence, lack of care will generally not be established unless the claimant’s actions are ‘so foolhardy as to amount to a wholly unreasonable disregard for his own safety’ in light of the situation on the ground at the time: Baker v TE Hopkins  1 WLR 966.
When Do the Claimant’s Actions ‘Contribute’?
The claimant’s lack of reasonable care must be a factual and legal cause of the damage or the extent of the damage: Stapley v Gypsum Mines  AC 663. The rules relating to factual and legal causation in this context are the same rules as apply to the tort of negligence.
The damage must also not be too remote (unforeseeable) a consequence of the claimant’s actions: Stapley v Gypsum Mines  AC 663. There is no need for the exact mechanism/extent to be foreseeable: Jones v Livox Quarries  2 QB 608.
Impact of the Defence
Effect of Contributory Negligence
If established, contributory negligence, the court can reduce the claimant’s damages. The reduction can be ‘to such extent as the court thinks just and equitable having regard to the claimant’s share in the responsibility for the damage’: Law Reform (Contributory Negligence) Act 1945, s 1(1). Only damages relating to loss of life and personal injury may be reduced: s 4.
How Much Should the Damages be Reduced?
The court should have regard to the relative importance of the claimant’s lack of care compared to the defendant’s negligence: Stapley v Gypsum Mines Ltd  AC 663. Generally, reductions of over 50% should not be given unless the claimant is judged to be more at fault than the defendant: Jackson v Murray  UKSC 5,  2 All ER 805.
Some situations have common reductions:
The failure to wear a seat belt usually results in a 25% reduction if wearing a seat belt would have avoided the damage, or 15% if it would have merely reduced the extent of the damage: Froom v Butcher  QB 286.
The failure to wear a helmet on a bike or motorbike usually results in a reduction of 15%, while wearing a helmet improperly results in a reduction of 10%: Capps v Miller  1 WLR 839.
The court is not permitted to make a 100% reduction: Brumder v Motornet Service and Repairs Ltd  1 WLR 2783.