Negligence — causation & remoteness

TOR.03 — Negligence: Causation & Remoteness

Once duty and breach are established, the claimant must prove the breach caused the damage and that the damage is not too remote. Both are required.

Factual causation — the "but for" test

Ask: but for the defendant's breach, would the harm have occurred? If it would have happened anyway, causation fails.

• Barnett v Chelsea & Kensington HMC — negligent A&E doctor not liable; the patient would have died of arsenic poisoning regardless.

Multiple/uncertain causes — the exceptions

• Material contribution: where breach materially contributed to a single indivisible injury, "but for" is relaxed — Bonnington Castings v Wardlaw; Bailey v MoD.
• Material increase in risk: in industrial-disease cases where science cannot pinpoint the cause, materially increasing the risk suffices — McGhee v NCB; Fairchild v Glenhaven (mesothelioma). Note Compensation Act 2006 s.3 — joint and several liability for mesothelioma.
• Loss of a chance generally fails in clinical negligence — Gregg v Scott (chance reduced below 50%, no recovery).

Legal causation — breaking the chain (novus actus interveniens)

A new intervening act can break the chain:

• Third-party act — must be truly independent/unforeseeable.
• Claimant's own conduct — if highly unreasonable — McKew v Holland (vs reasonable response in Wieland v Cyril Lord).
• Act of nature — if unforeseeable.

Remoteness — reasonable foreseeability of type of damage

• The Wagon Mound (No 1) replaced the old direct-consequence test (Re Polemis): damage must be of a reasonably foreseeable type.
• Extent/manner need not be foreseeable — Hughes v Lord Advocate (type foreseeable, extent need not be); Bradford v Robinson Rentals.
• Thin/eggshell skull rule: take the victim as you find them — Smith v Leech Brain. Foreseeability of type of injury is enough; its severity (due to the claimant's vulnerability) is irrelevant.

Common SBAQ traps

• Don't confuse the two stages — factual causation ("but for") is separate from remoteness (foreseeable type).
• The exceptions (material contribution / increased risk) are narrow — default is "but for".
• Type vs extent: the type of harm must be foreseeable; the precise way it happened and its scale need not be.
• Eggshell skull applies to physical and psychiatric harm, not just "egg shell personalities" — and it presupposes some foreseeable injury first.
• A foreseeable intervening act does not break the chain.