Causation in negligence - Apportionment of liability between tortfeasors

Learning Outcomes

After reading this article, you will be able to explain how English law apportions liability between multiple tortfeasors in negligence. You will understand the principles of joint and several liability, the statutory rules for contribution, and the doctrines of material contribution and material increase in risk. You will be able to apply these concepts to typical SQE1 scenarios involving multiple defendants.

SQE1 Syllabus

For SQE1, you are required to understand how liability is divided between multiple defendants in negligence claims. In your revision, focus on:

• the meaning and effect of joint and several liability in negligence
• how courts apportion damages between tortfeasors under the Civil Liability (Contribution) Act 1978
• the application of the material contribution and material increase in risk doctrines
• the distinction between divisible and indivisible injuries
• how these principles are applied in multi-defendant and multi-cause scenarios

Test Your Knowledge

Attempt these questions before reading this article. If you find some difficult or cannot remember the answers, remember to look more closely at that area during your revision.

1. What is the effect of joint and several liability in a negligence claim involving multiple tortfeasors?
2. How does the Civil Liability (Contribution) Act 1978 allow courts to apportion damages between defendants?
3. When is the doctrine of material contribution to damage applied, and what does it mean for liability?
4. In what circumstances will a court apply the principle of material increase in risk?

Introduction

When more than one defendant is responsible for a claimant’s injury or loss in negligence, the law must decide how liability and damages are divided. This article explains the key principles for apportioning liability between tortfeasors, including joint and several liability, statutory contribution, and the doctrines of material contribution and material increase in risk. These rules ensure claimants are compensated while distributing financial responsibility fairly among defendants.

Joint and Several Liability

Where two or more defendants have each contributed to a single, indivisible injury, English law imposes joint and several liability. This means the claimant can recover the full amount of damages from any one of the defendants, regardless of their individual share of fault.

Key Term: joint and several liability Where more than one defendant is liable for the same damage, the claimant may recover the full amount from any one defendant. Defendants are then left to sort out financial responsibility between themselves.

This rule protects claimants from the risk that one defendant is insolvent or untraceable. It also encourages defendants to seek contribution from each other, rather than leaving the claimant under-compensated.

Worked Example 1.1

Two drivers, A and B, are both negligent and cause a collision that injures a pedestrian, C. C suffers a single broken leg. C sues both A and B and is awarded £20,000 in damages. A is uninsured and cannot pay.

Answer: C can recover the full £20,000 from B. B can then seek a contribution from A for A’s share of responsibility, but C is not affected if A cannot pay.

Statutory Contribution Between Tortfeasors

The Civil Liability (Contribution) Act 1978 allows a defendant who has paid more than their fair share of damages to recover a contribution from other liable defendants. The court decides the amount of contribution based on what is just and equitable, considering each party’s responsibility for the damage.

Key Term: contribution The right of a defendant who has paid damages to recover a fair share from other defendants who are also liable for the same damage.

The Act applies to all torts, including negligence, and covers both joint and several liability situations.

Worked Example 1.2

C is injured in a car accident caused by the negligence of both D1 (70% at fault) and D2 (30% at fault). C recovers £100,000 from D1 alone.

Answer: D1 can claim £30,000 from D2 under the Act, so that each pays a share reflecting their responsibility.

Divisible and Indivisible Injuries

The way liability is apportioned depends on whether the injury is divisible (can be split between causes) or indivisible (cannot be separated).

• For indivisible injuries (e.g., a single broken bone), all defendants are jointly and severally liable for the whole loss.
• For divisible injuries (e.g., hearing loss caused by exposure to noise at different jobs), each defendant is liable only for the harm they caused.

Key Term: divisible injury An injury that can be separated into parts, each attributable to a different cause or defendant.

Key Term: indivisible injury An injury that cannot be separated into parts; all defendants are liable for the whole.

Material Contribution to Damage

When a claimant’s injury is caused by multiple factors, and it is impossible to say which factor caused what proportion of the harm, the court may apply the material contribution doctrine. If a defendant’s breach of duty made a material (i.e., more than minimal) contribution to the overall injury, that defendant is liable for the whole injury.

Key Term: material contribution Where a defendant’s breach of duty made a more than minimal contribution to the claimant’s injury, they are liable for the whole injury, even if other factors also contributed.

This doctrine is especially important in industrial disease cases, such as those involving exposure to harmful dust or chemicals from multiple sources.

Worked Example 1.3

E works for two employers, F and G, both of whom negligently expose E to silica dust. E develops a lung disease. It is impossible to say which exposure caused the disease, but both exposures materially contributed.

Answer: Both F and G are jointly and severally liable for E’s disease. E can recover full damages from either, and F and G can seek contribution from each other.

Material Increase in Risk

In some cases, especially where scientific uncertainty makes it impossible to prove which exposure caused the harm (such as mesothelioma from asbestos), the court may impose liability if the defendant’s breach of duty materially increased the risk of the claimant suffering the injury.

Key Term: material increase in risk Where a defendant’s breach of duty significantly increased the risk of the claimant suffering harm, and it is impossible to prove which exposure caused the injury, the defendant may be liable.

This principle is most often applied in mesothelioma cases, where exposure to asbestos from multiple employers cannot be separated.

Worked Example 1.4

H worked for three employers, each of whom negligently exposed H to asbestos. H develops mesothelioma, but it is impossible to prove which exposure caused the disease.

Answer: Each employer is jointly and severally liable for H’s loss, as each materially increased the risk of H developing mesothelioma.

Apportionment and Contribution in Practice

When a claimant recovers full damages from one defendant, that defendant can seek a contribution from others. The court will apportion liability based on each defendant’s share of responsibility for the damage, considering factors such as:

• the extent and seriousness of each defendant’s breach
• the duration and intensity of each defendant’s contribution to the harm
• any relevant conduct by the claimant (e.g., contributory negligence)

Novus Actus Interveniens and Multiple Causes

A novus actus interveniens (new intervening act) may break the chain of causation and relieve a defendant of liability for subsequent harm. However, where multiple defendants are independently negligent and their acts combine to cause a single injury, each remains liable for the whole loss unless the injury is divisible.

Key Term: novus actus interveniens A new, independent act that breaks the chain of causation, so the original defendant is not liable for harm occurring after the intervening act.

Summary

Key Point Checklist

This article has covered the following key knowledge points:

• Joint and several liability allows a claimant to recover full damages from any defendant responsible for an indivisible injury.
• The Civil Liability (Contribution) Act 1978 enables courts to apportion damages between tortfeasors based on their responsibility.
• The doctrines of material contribution and material increase in risk allow liability where causation cannot be precisely determined.
• Divisible injuries are apportioned between defendants; indivisible injuries result in joint and several liability.
• Novus actus interveniens may break the chain of causation and end a defendant’s liability for subsequent harm.

Key Terms and Concepts

• joint and several liability
• contribution
• divisible injury
• indivisible injury
• material contribution
• material increase in risk
• novus actus interveniens