UK: Certainty and Loss of a Chance in the Assessment of Damages (Or The Uncertainty: Loss of Chance)

Last Updated: 1 June 2005
Article by Samuel Townend

A Seminar given by Mr Samuel Townend on Tuesday 31 May 2005

  1. In this article I wish to discuss briefly general issues relating to certainty when it comes to the assessment of damages in construction and professional negligence cases and then to discuss the much troubled doctrine of loss of a chance in particular which, of course, is just one of a number of issues within the general topic of certainty.
  2. Certainty or the lack of it

  3. Certainty in this context is the extent to which it is possible to identify with precision and accuracy the loss or damage suffered and the exact extent it sounds in damages. Certainty frequently raises its head in the cases that we deal with. It is an unusual case indeed where it can be said and demonstrated with absolute precision the loss incurred by the Claimant. Most claims contain both liquidated and unliquidated losses and there are greater and lesser degrees of certainty in the claims made.
  4. The first point to note is that, of course, the burden of proof falls upon the Claimant. In relation to questions of liability, causation and the fact of loss the Claimant must prove these matters were more likely than not to have happened and, once accepted, they are taken as having happened. Conceptually it is only after these hurdles have been jumped that the question as to the assessment of damages arises. In practice, however, questions of scope of duty, causation and the fact of loss may be integral parts to the assessment process.
  5. The assessment of damages, once the fact of damage is proven, is in a different category as the starting point is that the Claimant is entitled to recovery. As Vaughan Williams L.J. in Chaplin v Hicks [1911] 2 K.B., the seminal case on the doctrine of loss of a chance, has said (at 792):
  6. "The fact that damages cannot be assessed with certainty does not relieve the wrongdoer of the necessity of paying damages."

  7. Just because it is not possible to ascertain damages precisely, so long as the Claimant does his best then that is sufficient. What constitutes "his best" forms the ground for debate in litigation, but the principle is clear. Bowen L.J. in Ratcliffe v Evans [1892] 2 Q.B. 524 CA, at 532-533 contains a guiding statement of the position:
  8. "In all actions accordingly on the case where the damage actually done is the gist of the action, the character of the acts themselves which produce the damage, and the circumstances under which these acts are done, must regulate the degree of certainty and particularity with which the damage done ought to be stated and proved. As much certainty and particularity must be insisted on, both in pleading and proof of damage, as is reasonable, having regard to the circumstances and to the nature of the acts themselves by which the damage is done. To insist upon less would be to relax old and intelligible principles. To insist upon more would be the vainest pedantry."

  9. Though this is a rather old-fashioned statement the same principles apply now as ever before. The emphasis on particularity and proof plays a major part in modern litigation: The TCC and the Queens’ Bench Division Masters in exercising their case management powers frequently now require:
    1. Detailed pleading of quantum at the earliest stage.
    2. Early disclosure of quantum documents- whether request by request or in the form of a "bible".

    I personally find this approach to be very useful. Depending on the nature of the case if anything this increased emphasis on the quantum exercise ought to be encouraged. All too often in the past there have been cases impossible of negotiation or settlement not because questions of liability are not capable of commercial assessment at a fairly early stage but because the position on quantum is entirely obscure to the advisers of the parties.

  10. I have chosen three recent cases briefly to take you through. Two are examples of where the Claimant is accepted as having done its best in terms of pleading and evidence and the court is prepared to make an assessment and one where it is not. The first case also demonstrates how the scope of a professional’s duty remains of huge significance in the identification of recoverable losses and how even hypothetical calculations of loss can be sufficient and acceptable. The further cases form a nice contrast, showing the (perhaps blurred) limits to which the Court is prepared to go in the absence of proof by the Claimant when it comes to assessment by particular reference to management costs.
  11. Scope of duty and certainty

    Earl Terrace Properties Limited v Nilsson Design Limited v Charter Construction PLC [2004] BLR 273

    The Facts

  12. E, a property developer, engaged N, architect, and C, contractor, to refurbish some houses in Kensington for future sale. Water penetration in the rear basement structures took place as a result of inadequate installation of a water membrane. This was said by E to have caused 15 months delay to the completion of the project while remedial work was carried out. E brought an action against the architect, N, for failure properly to design or specify details connected with the membrane. N in turn joined C for a failure in workmanship.
  13. A substantial claim of £6m by E was calculated by reference to funds of E that were "held" in the project for 15 months longer than they would have been had the defects in the works not occurred. E had funded the project by way of a financial credit agreement with another company called V. V was an ultimate parent company (at some remove) of E and had lent money to E on various different bases, including some that were entirely interest free. The losses claimed were not therefore calculated on the basis of interest charges, but on "loss of use" of the funds calculated on a hypothetical basis- the London Inter-Bank Offered Rate plus 2%. A further complication was presented because in the 15 month delay the housing market improved substantially such that the ultimate delayed sales were for prices far higher in value than they would have been absent any delay. The Defendants’ case was that the Claimant has to give credit for these gains.
  14. A trial of a preliminary issue was held on the following agreed issues:
    1. Is E entitled to be compensated by applying the hypothetical interest rate?
    2. Is E obliged to give credit for the fortuitous increase in the market value of the houses?

    Loss of use calculated on a hypothetical basis

  15. As to issue (1) the Judge made the following findings. Generally, no damages are recoverable if no loss of any kind can be established. If it can be established that a party lost the opportunity to make commercial use of the money in question but cannot precisely quantify that loss, it is in principle acceptable for a claimant to quantify that loss by reference to a reasonable return that it could have earned by placing the money on deposit and then collecting a reasonable commercial rate of interest over the relevant period of delay. Just because the calculation is theoretical, if it is the best attempt at demonstrating the loss, then that is acceptable.
  16. There is an analogy with the readily accepted but somewhat theoretical basis of calculation of losses in personal injury cases by reference to actuarial tables in Kemp & Kemp.

  17. As to issue (2) the judge held that no credit is to be given for the fortuitous increase in house prices resulting in the houses being able to be sold by the Claimant at a much higher rate than 15 months before. The sale price is unconnected with the original breach. Uncertainties in the housing market can usually demonstrably be shown not to have any connection with the breach. The Judge gave two reasons for his conclusion:
    1. If there was a downward move in the housing market, the additional loss incurred would not be within the scope of the duty of the architect/contractor and would not ordinarily additionally be required to pay damages as a result of that change. The vicissitudes of the housing market are outside the contemplation of the parties at the time of contracting and outside the scope of any duty. The converse must therefore be true for any rise in the housing market. Thornton QC:
    2. "…the rise or fall is unconnected with the negligent act and too remote from it in addition to being outside Nilsson’s [the architect] scope of duty."

    3. Another reason is that the sale occurred long after the breach had occurred. Ordinarily in defects cases damages for negligence and breach of contract are assessed by reference to the date on which the breach of contract or duty occurred since that is when the damage caused by the breach arose (said the Judge). Changes in the market for houses some months later is not a loss that can be attributable to the breach.
    4. That said, Thornton QC caveated his conclusion by stating that this question of recoverability is very fact sensitive.

    Certainty and management costs

  18. The Earl Terrace case demonstrates the importance of the definition of the duty owed by the culpable professional when coming to assess damages. Of course, identification of causation and loss are also of critical importance. Again, here one refers back to the burden of proof. Below described are two recent cases in the context of claims for management costs incurred as a result of a construction professional’s breach of duty. They demonstrate principally that the law itself remains a good degree uncertain on questions of certainty at the margins. More particularly, they demonstrate that the boundary where causation ends and quantification begins is at best somewhat difficult to discern and, at worst, not governed by legal principle, but merely by the Judge’s view of the merits of the case in point.
  19. Phee Farrar Jones v Connaught Mason [2003] CILL 2005

  20. CM, a contractor, contracted with PFJ to carry out refurbishment work for PFJ. CM caused floods which resulted in PFJ having to move to alternative premises while the prolonged work was completed. The costs of the alternative premises were awarded by the court, but the question turned to whether PFJ were entitled to recover costs in respect of wasted management time spent dealing with the floods and the aftermath. In answering this question the Judge, HHJ Toulmin QC CMG said no, stating in terms that if management expenses are to be claimed they must be discrete (i.e. separately identifiable), such as by reference to overtime, or by reference to specific loss of revenue, which otherwise would have been obtained. Evidence that the managers spent significant time on dealing with the problems as a result of the flood was not enough.
  21. This is, I think, in stark contrast to another recent water proofing case where a more liberal approach to the award of management time spent dealing with consequences of a professionals’ breach of duty has been taken:
  22. Try Build Ltd v Invicta Leisure Tennis Ltd (2000) 71 Con LR 140

  23. In this case the Judge (HHJ Bowsher QC) accepted that the senior managers in question were not paid overtime and that their costs would have been incurred in any event, but nevertheless went on to award damages in respect of the loss of the managers time which ought to have been devoted to his ordinary duties:
  24. "even if the time lost was time which might have been spent looking out of the window thinking. The value of that time lost to the company may be enormous or small, but it can only be assessed by reason of the cost of the employee to the company." (at 181- 182)

    The Judge discounted the costs claim giving the benefit of the doubt on quantification to the Defendants, but nevertheless made a significant award to the Claimant on this general evidential basis.

  25. My conclusion in relation to these lost management costs claim cases and more widely where questions of certainty are present is:
    1. In this area (as in others) there is a lack of certainty of outcome where hypothetical or estimated claims are made.
    2. It is always worth a Claimant characterising the process of identifying damages in a given case as a pure assessment or quantification exercise and inviting the Court to do its best on the material provided (implicitly or expressly, if necessary, arguing that the burden of proof has been met). Conversely it is worth a Defendant arguing in cases where there is a lack of certainty in identifying the damages that the Claimant has yet to prove causation.
    3. Appeal Court guidance on management costs would be useful!

    The doctrine of Loss of Chance

  26. The doctrine of loss of a chance is a peculiar type of case where there is a lack of certainty in identifying loss and damage and resulting money damages. The intellectual and practical problems associated with this doctrine dwarf those described earlier. It is best understood by distinguishing it:
  27. "In determining what did happen in the past the court decides on the balance of probabilities. Anything that is more probable than not it treats as certain. But in assessing damages which depend upon its view as to what will happen in the future or what would have happened in the future if something had not happened in the past, the court must make an estimate as to what are the chances that the particular thing will or would have happened and reflect those chances, whether they are more or less than even, in the amount of damages which it awards." [Mallett v McMonagle [1970] AC 166, 176 per Lord Diplock].

  28. The distinction thus is between case where the assessment of damages involves analysis of:
    1. Past Events: The Claimant is awarded all or nothing on the basis of the balance of probabilities and for which the doctrine of loss of a chance has no application. See Davies v Taylor [1974] A.C. 207, 212-213:
    2. "If evidence shows a balance in favour of [something] having happened then it is proved that it did in fact happen" [213]


      Amber and Brian involved in a car accident. If on the evidence there is proof on the balance of probabilities that Amber drove into Brian’s car (Brian not being at fault at all), Brian will receive the cost of the repairs to his car from Amber.

      And those cases where the assessment of damages involves analysis of

    3. Future Events or more usually a mix of past events and future events: A percentage will be awarded, because the damages are based on probability or ‘chance’


    Amber, in fact an excellent driver, entered into a contract with Brian, Formula 2 founder, in which Brian agreed to give Amber the opportunity to be selected, after an interview, to be a grand prix racing driver for a year. Amber received the invitation for interview late. She missed it. Brian then refused to interview her at all thereby, the Court held, breaching the contract. Amber claimed that due to Brian’s breach of contract she had lost an opportunity to pursue a career in racing driving altogether and asked the court to assess her loss.

    This is a loss of a chance case as the process of assessing damages involves analysis of the future event of the interview and the chance of Amber becoming appointed a racing driver.

  29. This example is in fact analogous to the facts in Chaplin v Hicks [1911] 2 K.B. 786, the seminal loss of a chance case. Amber the racing driver hopeful was in fact Miss Hicks, an early twentieth century contestant for Pop Idol and the contest was for an engagement as an actress on the stage.
  30. The Facts

  31. An advertisement was placed by Mr Chaplin, a theatre manager and actor, in a newspaper for applications for engagements as actresses, with photo. The photographs were to be voted for by the readers of the paper and those with the highest votes would be selected for interview and go forward for the chance to be selected by Mr Chaplin himself. Miss Hicks received a high number of votes from the readers and was asked by letter to attend for interview. She missed the interview. Mr Chaplin refused her a further appointment for interview (which the court deemed a breach of contract). She claimed damages from him for breach of contract for the loss of her chance of gaining an engagement.
  32. When it came to assessing what those damages should be the court of first instance (and indeed the CA) had a get out clause in this case, namely that it was the jury who plucked a figure out of the air without giving reasons of course and awarded it to Miss Hicks (in this case £100).
  33. The CA was solely concerned with the question of whether Miss Hicks was entitled to a remedy for her loss of a chance in principle. Could all Miss Hicks in fact receive be nominal damages as the loss was incapable of assessment?
  34. The three members of the CA were unanimous that she could receive damages for this loss. Vaughan Williams L.J. held that the presence of all the contingencies upon gaining the prize meant that carrying out the calculation was "not only difficult but incapable of being carried out with certainty or precision" [791] However, his Lordship propounded:
  35. "I do not agree with the contention that, if certainty is impossible of attainment, the damages for breach of contract are unassessable…I only wish to deny with emphasis that, because precision cannot be arrived at, the jury has no function in the assessment of damages"

  36. Vaughan Williams L.J. plainly felt that to deprive Miss Hicks from any remedy for her loss of a chance would cause unfairness, giving as his reason:
    1. In this case there is a wrongdoer, and why should he be relieved from compensating the Claimant merely because the damages cannot be assessed with certainty [792]; and
    2. (Demonstrating that "merits" underlay the decision in this particular case) as a result of Mr Chaplin’s breach of contract it was apparent that there may be a slur upon Miss Hicks in her professional capacity which might result in a diminution in value of her services as an actress when she applied for an engagement in the future [797]

    Thus in this case it did not matter that there was no certainty in winning the engagement, it was sufficient that it was proven that Miss Hicks had lost the chance of winning altogether.

  37. Lord Reid in the Davies case explained this by reference to past events and future events:
  38. "You can prove that a past event happened but you cannot prove that a future event happened and I do not think that the law is so foolish as to suppose that you can. All that you can do is to evaluate the chance. Sometimes it is virtually 100%: sometimes virtually nil. But often it is somewhere in between. And if it is somewhere in between I do not see much difference between a probability of 51% and one of 49%" [213]

  39. This has been echoed by Lord Nicholls in the recent and important House of Lords decision in Gregg v Scott [2005] UKHL 2 (27 January 2005), a medical negligence case which I will come on to, at paragraph 43, where he states that to make a distinction in relation to future events would be arbitrary and that the law would be likened to a ‘proverbial ass’ if it made such distinctions. Note, however, that this is a dissenting judgment and that there is a now settled distinction to be made between pecuniary cases, such as Chaplin and the construction and professional negligence cases that we are likely to be involved in, and medical negligence cases.
  40. Hotson v East Berkshire Area Health Authority [1987] A.C. 750 HL is the leading case in the personal injury field setting out the limits of the loss of a chance doctrine.
  41. Example

    Amber fell over and injured himself so seriously that she had a 75% chance of permanently being unable to walk. The hospital failed to deal with her soon enough, increasing her chances of permanent disability to 100%, a certainty, does Amber receive damages for 25% loss of chance of recovery?

  42. It would appear not. The House of Lords in Hotson v East Berkshire Area Health Authority [1987] A.C. 750 used the ‘past events’ test. The injury was taken to be the result of a past event and nothing in the future could change the state of the injury. On the facts the delay in treating the injury at the hospital had no effect. Lord Mackay held that the Claimant had no chance of avoiding avascular necrosis by the time of arrival at the hospital. Before the hospital’s negligence occurred the damage was already done. [785; see Lord Ackner at 792 "inevitable";] This has later been interpreted as there being "no significant uncertainty about what would have happened if treated promptly" [Gregg v Scott Lord Nicholls at para 38].
  43. Hotson set out clear blue water between the treatment by the Courts of medical negligence cases and economic cases (a distinction I will shortly return to).
  44. The next seminal case in the pecuniary loss line (as opposed to the medical negligence cases) is Allied Maples Group v Simmons & Simmons [1995] 1 W.L.R. 1602, CA.
  45. The Facts

    This is a solicitors negligence case where C, a retailing company, instructed D, solicitors, to act for them in the takeover of assets of a smaller retailing company. In the process of the negotiation D gave C negligent advice about how to cater for contingent claims concerning properties presently leased by the smaller retailing company which was being taken over. The Court found, at first instance, that there was a real chance that properly advised C would have negotiated with the vendor to give proper protection/reduced purchase price and awarded damages on the loss of a chance basis. On appeal Stuart Smith LJ gave some guidance when coming to these types of cases laying out 3 categories where loss occurs which can be separately distinguished (1609- 1611):

    1. The positive act where the question of causation is one of historical fact. The court has to determine on the balance of probability the breach caused the Claimant’s loss. Once established on the balance of probability, that fact is taken as true and the Claimant recovers his damage in full. (Eg. first example- Amber losing her leg in road traffic accident)
    2. The omission, for example, a failure to provide proper equipment, give proper instructions or advice. Here the question of causation is not one of historical fact, but on the answer to the hypothetical question, what would the Claimant have done if the equipment had been provided or the instruction or advice given? This can only be a matter of inference to be determined in all the circumstances. Although the question is a hypothetical one, it is well established that the Claimant must prove on balance of probability that he would have taken action to obtain the benefit or avoid the risk. Once proven, he is entitled to recover in full.
    3. On Stuart-Smith LJ’s analysis the loss of a chance doctrine is of application where the Claimant’s loss depends on the hypothetical action of a third party, either in addition to action by the Claimant (as in the case presently under consideration) or independently of it. In this analysis the Claimant succeeds provided that he shows that there was a substantial chance (rather than a merely speculative one) of the third party acting so as to confer the benefit or avoid the risk and substantial chance is then reflected in the quantification of damages.

  46. In pecuniary loss of a chance cases therefore Allied [1611] sets out a two stage test (depending on the circumstances) [see Graham Reid ‘The Hypothetical Outcome in Professional Negligence Claims’ (P.N. Vol 17, No. 2 129, 132) "the dual standard"]:
    1. C need only prove a substantial chance of a third party’s actions (what is substantial?); and
    2. C must [not may] establish on a balance of probabilities what his own hypothetical actions would have been.

  47. On the question of what constitutes "substantial chance" Stuart Smith LJ went on to say that C must show as a matter of causation that he has a real and substantial chance of the third party acting in such a way as to benefit him as opposed to a speculative one [Allied at 1614]; successive cases have said that the "chance ignored if merely speculative".
  48. Allied provides at least a working checklist for practitioners in our sphere of work where the loss is pecuniary (as opposed to the more troubled area of medical negligence). Note, however, that subsequently Lord Nicholls in Gregg v Scott (dissent) [at 19] rejected that Stuart Smith L.J. intended this to be a precise and exhaustive statement of the circumstances in which loss of chance may constitute actionable damage and held that his proposition should not be so understood.
  49. Further, this test though apparently settled should be approached with a health warning. It has been argued by Neuberger L.J. in his recent lecture to the Professional Negligence Bar Association (9th February 2005) that he is not clear that there is any good reason why a Claimant has to prove what his hypothetical action would have been on the balance of probabilities, but not that of a third party. He queries whether a Claimant is in fact is any better position to prove what he would have done than what a third party would have done or the desirability of having essentially to rely upon what a Claimant says he would have done. There are also, the Judge points out, practical difficulties for a Judge in coming to these cases with the Allied test (35):
  50. "There are also difficulties where the question turns, as it so often does, on what both the claimant and a third party would have done – e.g. would they have agreed a reduction in price or settled a case. Deciding what two parties would have agreed is difficult enough: if one has to decide what one party would have agreed on the balance of probabilities, but then assess damages by reference to the chances of what the other party would have agreed, a judge may be placed in an almost impossible position."

  51. An example of a "hard case" in the pecuniary cases line in our field is J Sainsbury Plc v Broadway Malyan 61 Con L.R. 31:
  52. The Facts

    C, Sainsbury, decided build and open a large supermarket. C therefore employed D, as architect, and E as consulting engineer. Post completion an arsonist set fire to the supermarket largely burning it down. On expert evidence it was proven that the fire had spread quickly and into the main store area. The reason for this was that D had in breach of contract and negligently (in designing and supervising the works) failed to ensure that the construction of a fire compartment wall was correct. It was argued by C that but for this negligence the fire would have been significantly contained by the fire brigade (as the wall should have had two hours fire resistance not half an hour). D, architect, settled with C and subsequently pursued E, consulting engineer, for a contribution on the basis that E was:

    (1) Involved in the re-design of the fire wall; and

    (2) Specifically consulted about the same and approved the construction.

    [Note the architect alleged that the engineer had an equal design responsibility for the design because it failed to observe or draw attention to an obvious defect within its own sphere of competence. Crucially the architect claimed that the engineer owed a duty to Sainsbury in respect of the fire resistance of structural elements]

  53. Is the action and the consequent contribution proceedings a loss of chance case? D had settled with C on the basis that it was not and paid over significant sum (over £7 million) on the basis that if proven liable he would be liable for the whole damage. In the contribution proceedings it was therefore argued by D that this was a type 1 Allied case (proof of causation of a past event on the balance of probabilities) and E, seeking to minimise their exposure argued that because of the intervention of the fire brigade it was a type 3 loss of a chance case.
  54. The architect, D, gave convincing reasons for arguing that this was a type 1 case, in particular:
    1. Loss of a chance had no application because the defects in the wall caused the fire to spread, and thus direct physical damage to the property; and
    2. None of the loss of chance cases were concerned with direct physical damage to property caused by D’s negligence but were instead concerned with the possibility of having lost the chance to obtain a benefit he might have got but for the D’s negligence (e.g. Chaplin – engagement).

  55. The engineer argued that all that had been lost was a chance of saving the main part of the supermarket. He argued that any damages which he had to be pay should be decreased to a percentage of the settlement figure and argued that the two questions properly for the court were:
    1. If they had designed a competent fire wall, would the fire service have had a significant and measurable chance to save more?; and
    2. Only if yes, then evaluate that chance.

  56. HHJ Lloyd Q.C., agreeing with E held [68] that he had no doubt that this was a loss of a chance case because of the way that Sainsbury’s argument against the architect was put, which implicitly supposed that the fire would have been held at the wall. Thus:
    1. As a matter of causation damage to the shop would depend on the ability of the fire brigade to contain the fire at the wall with its help.
    2. This was the hypothetical action of a third party (the fire brigade) – i.e. the argument is that the fire brigade would have tackled the fire in such a way that the affected part of the shop would have been saved.
    3. The balance of probabilities approach would not be appropriate due to the intervention of the fire brigade. This analysis was necessary as Sainsbury suffered no loss as a result of the architect/engineer’s assumed breach until the wall was put to test in the fire. Inevitably consideration had to be given to the intervention and abilities of the fire brigade. A hypothetical assessment of their competence would have reduced Sainsbury’s claim against D (had it not already settled).

  57. In coming to his judgment the Judge considered whether the settlement was a reasonable one. The court assessed the chance that the sales area would have been saved if the wall had been designed properly was only 35% due to the evidence that the fire would have swept around the roof and exposed the firemen in the affected area probably leading to unacceptable risks so that any attempt to hold the fire in itself at the wall would have been abandoned as too the affected area [71-2].
  58. One view [Graham Reid in the Professional Negligence Journal Vol. 12, No. 2 (2001) at 133] is that it was incorrect for HHJ Lloyd Q.C. to base his assessment on the mere presence of a third party’s actions in the causal path which the C would have had to establish in order to make out its hypothetical outcome. It is certainly troubling for anyone advising on these sorts of cases that it may be necessary to consider (as HHJ Lloyd QC appears to have done) the locality and abilities of the local emergency services when assessing percentage chance.
  59. The difficulties in considering all "loss of a chance" cases, to my mind, come down to a tension between principle in legal and logical analysis on the one hand and doing a manifest unfairness to a party on the other hand. In judicial terms, those who have feared and sought to limit the loss of a chance doctrine resist it on the basis of consistency of legal principle and logic underpinned by a public policy argument of not wishing to open "the floodgates of litigation". Those who have taken sympathy with the doctrine have fallen into another camp, approving and applying the doctrine on the basis of practicality and fairness. This tension is reflected in the whole case history of the doctrine and cannot be escaped. While to a degree it results in many cases remaining open to debate and uncertainty of outcome for us acting as advisers to our clients, on the other hand it does permit scope for imaginative and strong case presentation and advocacy having an effect in a given case (an opportunity for solicitors and barristers truly to earn their money!). While precedents are set and rules can be taken and applied the precise scope and extent of the doctrine is somewhat elastic.
  60. The tension between uncertainty and unfairness is displayed quite plainly in the last case that I wish to talk about, Gregg v Scott [2005] UKHL 2 (27 January 2005). The true contentious nature of the doctrine is captured in the judgments of both the CA and the HL, who were split 2:1 and 3:2 respectively against the application of loss of a chance in the case. Even the reasoning of each of their Lordships contains many differences:
  61. The Facts

    Gregg discovered a suspicious lump. A doctor, Scott, was dismissive of it and failed to send Gregg for any tests at all. The lump develops and whilst time runs on, Gregg’s chance of survival depreciates significantly, critically in this case the chances of disease free survival for ten years (on accepted expert evidence) were decreased from 42% when Gregg first consulted the doctor, to 25% at the date of trial (at first instance). Does Gregg receive damages for his loss of chance in surviving for longer, but for the negligent acts and omissions of the Doctor? Is this any different to the facts of Hotson?

  62. On some views this is different to Hotson. In Latham L.J.’s dissenting judgment in the CA he distinguished the case because in Hotson the avascular necrosis was inevitable and untreatable, whereas in Gregg at the time of the breach the tumour was treatable- the tumour grew and the chances of successful treatment were reduced. There was evidence that the cancer had spread by reason of the negligence of the doctor and that was all that was necessary to found the claim in damages. The conclusion Latham LJ reached, however, was rejected by the majority in both the CA and HL.
  63. The majority [Lords Hoffman, Phillips & Baroness Hale] held that the question to be answered was the simple one, and that as, on the balance of probabilities, Mr Gregg was not going to survive for 10 years whether or not he had the treatment, he was therefore not entitled to recover damages. Lord Hoffman relied on principle and authority and the proposition that the law deals with lack of knowledge by invoking the burden of proof [Para 79]. References were also made to the cost implications for the NHS [Para 90] (cf minority view that this was something which had to be borne by the NHS and was for the legislature to deal with [52-6]). Lord Phillips had concerns about assessment in terms of percentages (i.e. the line is drawn in the sand by the balance of probabilities and that is that) [Para 170]. He was also influenced by the fact that by the time of the House of Lords hearing Mr Gregg was still alive! Baroness Hale looked at it from the other end- pointing out that a claimant under an expanded loss of a chance doctrine "with a better than evens chance would still only get a proportion of the full value of [his] claim".
  64. The minority [Lords Nicholls & Hope] held that Mr Gregg’s chance of survival was 17% less than it would have been and this was a real disadvantage which Mr Gregg suffered as a result of the Doctor’s negligence. [see interesting analysis by Lord Nicholls [para 121] – the Doctor’s negligence resulted in Mr Gregg’s loss which was itself caused by a physical injury, namely the enlargement of a tumour].
  65. A distinction was thereby drawn by the majority of the Lords that you could not compare the positions of Miss Hicks and Mr Gregg [See paras 83, 218] as Miss Hicks’ case was one of economic loss and Mr Gregg concerned physical injury. A clear distinction made was between pecuniary cases and medical negligence cases. The former said to be relatively straightforward to assess loss and damages, but the latter simply too hypothetical. Intellectually this is fairly hard to accept, but plainly on policy grounds it is supportable.
  66. One rather philosophical explanation given by an academic of why the courts distinguish between financial loss and med. neg. claims is the difference between deterministic events, where balance of probabilities is appropriate, and indeterministic events, where the loss of chance doctrine is appropriate [see Helen Reece, "Loss of Chances in the Law" (1996) 56 M.L.R 188]. Reece gives the example of tossing a coin. Where the coin is yet to be tossed, the caller does not know whether it will land heads or tails and there is a 50% chance that he will be right in calling heads of tails. The situation is indeterministic: there is no right answer. If the coin has already been tossed, but it is still covered, there is still the same chance of calling correctly – 50%. However it is submitted by Reece that the fact that no-one may know the outcome, because the coin is covered, does not prevent there being a right answer – the coin has been tossed, the outcome is deterministic. This is analogous to the tumour in the Gregg case and the injury in the Hotson case. Human actions in contrast are indeterministic, Reece says, as you cannot know how a human will act. You do not know whether Miss Hicks would win the beauty contest (Chaplin) or whether a vendor will agree to amend the conditions of a sale (Allied). Assessment of damages on the basis of loss of a chance is therefore appropriate. Medical outcomes are arguably deterministic because they depend on physical events which have already occurred, even though they may be impossible or difficult to predict [see 40]. Proof on the balance of probabilities is therefore appropriate.
  67. Neuberger L.J. in his lecture at Inner Temple on 9 February 2005 described the Gregg decision as a victory for legal consistency over fairness. It certainly would appear to be ‘one in the eye’ for the so-called ‘compensation culture’.
  68. It is also, however, probably fair to say that the medical negligence cases pose particularly difficult problems, putting aside questions of public policy, as thrown into the mix are the limitations of scientific and medical knowledge, understanding and treatment [see para 36 Gregg v Scott]. The hypothetical considerations in those cases are only as good as the scientific and medical knowledge at that time. This, perhaps, justifies the different treatment of pecuniary and med. neg. cases.
  69. Conclusions

  70. Having written this piece it is with some trepidation that I reach conclusions in an area of the law that has so obviously not come to a settled view. The best I can do is to make some general points by way of a starting point for practitioners:
    1. In each of these cases there will be a tension between principle and fairness. These will underpin arguments of those on each side and will be what the Court is interested in hearing. It is important to tailor the arguments accordingly.
    2. There is a distinction between pecuniary cases, where the doctrine is pretty well established, and med. neg. cases where it certainly is not.
    3. In pecuniary cases identify whether or not the recovery sought would have been dependent upon the hypothetical action of a third party had there been no breach. If so, then you are or may be in "loss of a chance" territory and need to present the case accordingly.
    4. In med. neg. cases where the negligent act caused a change in chances of recovery by less than 50% prepare for your case to go all the way to the House of Lords!

    Samuel Townend is a Barrister practising from Keating Chambers and specialising in construction, engineering and technology related law along with professional negligence cases within these specialist areas.

    The articles and papers published by Keating Chambers are for the purpose of raising general awareness of issues and stimulating discussion. The contents must not be relied upon or applied in any given situation. There is no substitute for taking appropriate professional advice.

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