Facts
- Mr. Gregg consulted Dr. Scott regarding a lump under his arm.
- Dr. Scott negligently misdiagnosed the lump as benign, leading to a nine-month delay in proper treatment.
- During the delay, the cancerous tumor progressed significantly.
- At trial, expert evidence showed that with prompt diagnosis, Mr. Gregg's chance of survival would have been approximately 42%, which dropped to 25% after the delay.
- The central issue was whether the reduction in survival prospects constituted a compensable loss as a loss of a chance.
Issues
- Whether a claimant can recover damages for loss of a chance of a better outcome where a defendant's negligence reduces survival prospects below 50%.
- Whether the reduction in the prospect of survival due to delayed diagnosis constitutes a distinct and compensable head of damage.
- Whether the principle of causation should be extended to permit proportionate recovery in cases where definitive proof of causation is problematic due to medical uncertainty.
Decision
- The House of Lords by a 3-2 majority held that loss of a chance is not a recoverable head of damage in medical negligence.
- The majority (Lord Hoffmann, Baroness Hale, and Lord Phillips) refused to extend causation to permit damages for reduced chances of a favourable outcome.
- Lord Hoffmann noted difficulties in defining the relevant injury and distinguished evidential from medical uncertainty.
- Baroness Hale cited practical and policy concerns regarding the complexity and predictability of a proportionate damages system.
- Lord Nicholls and Lord Hope dissented, arguing a significant lost chance is still a compensable harm.
- The appeal was dismissed, upholding the requirement to prove causation on the balance of probabilities.
Legal Principles
- Causation in negligence traditionally requires proof on the balance of probabilities that the defendant's breach caused the harm.
- Loss of a chance is not a recognized head of damage in medical negligence when the chance was below 50% at the outset.
- Proportionate damages for loss of chance are generally unavailable except in certain cases (e.g., third-party actions or special circumstances as in mesothelioma/asbestos exposure).
- Policy and practical concerns were essential to maintaining the orthodox causation approach.
- The decision confirmed and followed the precedent in Hotson v East Berkshire Area Health Authority [1987] AC 750, distinguishing exceptions such as Fairchild v Glenhaven Funeral Services Ltd [2002] UKHL 22 and Perry v Raleys Solicitors [2019] UKSC 5.
Conclusion
The House of Lords reaffirmed the traditional causation test in negligence, holding that damages are not recoverable for loss of a chance of a better medical outcome. This approach, influenced by policy and practical concerns, remains authoritative except for narrow exceptions involving third-party actions or specific conditions such as mesothelioma.