3. Loss of a Chance

The award of damages for lost chances has created a fiery doctrinal debate in England and France. The concept of loss of chance generally relates to a situation where the injured party claims damages for the lost chance of either gaining a favourable outcome or avoiding harm. At first sight, the stances of the English and French courts differ greatly. In France, the courts have been persuaded that a lost chance can be ‘certain’ loss. In England, the courts have shown less enthusiasm. But, a closer analysis does provide evidence of parallels both in the case law and in academic commentary.

Initially, an analysis will be made of the manner in which the lost chance doctrine has been dealt with in the French and English cases. In a second section, the relevant doctrinal debate will then be analysed. Comparative law conclusions will be drawn in a culminating section.

3.1. The Lost Chance Doctrine in English Law

The use of probability or chance is by no means excluded in English law. It is a well-established principle that damages for loss of a chance are recoverable in contract.¹³⁷ Probabilistic analysis also features in tort law, for instance in determining future loss of earnings in a personal injury action.¹³⁸ But this relates to the quantification of damages. The real (p.204) controversy in tort law relates to the prior question of liability and lost chance. This was examined in the leading case of Hotson v East Berkshire Area Health Authority.¹³⁹

In Hotson, the claimant fell out of a tree and was taken to hospital. Doctors negligently failed to diagnose that he had sustained an acute fracture of the left femoral epiphysis. Not until five days later did the claimant get a correct diagnosis and thus receive proper treatment. He subsequently sustained avascular necrosis, resulting in significant disability, and brought an action against the initial doctors claiming damages for inter alia the lost chance of avoiding the onset of avascular necrosis.

At first instance, it was held that Hotson was entitled to damages for the 25 per cent chance of full recovery he had lost, and he was thus awarded a quarter of the damages represented by his resultant disability.¹⁴⁰ The Court of Appeal affirmed the decision of the trial judge. It was accepted that the lost chance was distinct loss, capable of recovery in tort as well as in contract. As Dillon LJ asserted, ‘the fundamental question is what is the damage which the claimant has suffered? Is it the onset of the avascular necrosis or is it the loss of the chance of avoiding that condition? In my judgment, it is the latter.’¹⁴¹

In the House of Lords, their Lordships side-stepped the central issue of whether a lost chance could be recognized as damage recoverable in tort. Rather, attention was focussed on the question of the causal link between the doctor's negligence and the onset of the claimant's physical injury. Lord Bridge emphasized that ‘[u]nless the claimant proved on a balance of probabilities that the delayed treatment was at least a material contributory cause of the avascular necrosis he failed on the issue of causation’.¹⁴² After analysing the trial judge's findings of fact, his Lordship concluded that the 75 per cent probability that the claimant would have developed his condition even with proper treatment amounted ‘to a finding of fact that the fall was the sole cause of the avascular necrosis’.¹⁴³ Their Lordships therefore rejected the damages claim.

The Hotson decision leaves little room for the application of the lost chance concept in medical malpractice cases. Although their Lordships did not specifically reject the possible acknowledgement of a lost chance as a distinct head of damage, their insistence on the traditional requirement (p.205) of proving that, on the balance of probabilities, the causal link between the defendant's breach of duty and the final disability militates against the future application of the doctrine in this sphere.¹⁴⁴

Beyond the medical sphere, other claims in tort have suggested a less restrictive approach in English law. There have been a sprinkling of cases involving the lost expectation of financial gain. In Allied Maples Group Ltd v Simmons & Simmons,¹⁴⁵ it was indicated that claimants could gain damages from their solicitors for the lost chance of negotiating proper protection against contingent liabilities in a contract for the takeover of assets.¹⁴⁶ In another case, damages were granted for the lost chance of successful litigation due to the negligence of a solicitor in failing to abide by the limitation period.¹⁴⁷ Finally, it has been indicated that lost chance damages may be awarded for lost employment opportunity.¹⁴⁸

On the basis of these cases, it is difficult to give a broad explanation of where lost chance damages can be recovered and where they cannot. On the one hand, the lost chance doctrine cannot entirely be ruled out in English tort law. On the other, it is clear that English law, unlike French law, does not recognize loss of a chance as a general type of damage. Certainly, in personal injury cases, the all-or-nothing rule reigns supreme: if a claimant proves on the balance of probabilities that the defendant's breach of duty actually caused the resultant injury then full recovery follows; no discount will be made for a less than 50 per cent chance of having caused the loss. In terms of public authorities, liability in the medical sphere is of great significance, and it is in this sphere that an Anglo-French comparison is the most striking.