England and Wales Court of Appeal (Civil Division) Decisions

IN THE COURT OF APPEAL (CIVIL DIVISION)
ON APPEAL FROM THE NORWICH COUNTY COURT
His Honour Judge Curl
7NR03507

		Royal Courts of Justice Strand, London, WC2A 2LL
		03/11/2011

Lord Justice Moore-Bick :

1. The appellant, Mr. Smithurst, was employed by the respondent, Sealant Construction Services Ltd, as a concrete diamond core driller. His work involved the handling of heavy equipment and inevitably put some strain on his back. For the purposes of his job Mr. Smithurst was provided with the use of a van, but unfortunately the locking mechanism of the rear doors was defective, with the result that they could not be opened from the outside. In order to open the doors, therefore, Mr. Smithurst would lean over the front seats, half crawling between them, and over a partition designed to prevent objects carried in the van from being thrown into the driving compartment so as to get at them from the inside.
2. On the morning of 16^th March 2006 Mr. Smithurst attempted to open the rear doors of the van in the usual way. However, in the rear compartment were various tools and equipment, including two 25 litre barrels of water, which he had to manoeuvre out of the way in order gain access to the doors. He clambered half way into the rear of the van and began to move the barrels and other equipment out of the way to make room for him to reach the doors. He completed that part of the task, but as he began to pull his body into the back of the van he felt a pain in his leg which he thought was cramp. Within a short period of time the pain grew considerably worse and his wife took him to hospital. It turned out that he had suffered a massive prolapse of the disc between the fifth lumbar vertebra and the first sacral vertebra (L5/S1).
3. On 20^th March Mr. Smithurst underwent surgery which was technically successful in as much as the extruded section of the disc was removed and the pressure taken off the nerves within the spinal column, but his symptoms did not improve and he continues to suffer pain in his back and legs and other distressing symptoms. As a result he is incapable of working.
4. Mr. Smithurst's continuing symptoms are the result of damage to the cauda equina, a bundle of nerve fibres at the lower end of the spinal cord. The effect of the prolapse was to extrude a substantial amount of material from the body of the disc into the space within the spinal column thereby compressing and damaging the nerves at that point.
5. In due course Mr. Smithurst brought proceedings against the respondents seeking to recover damages for personal injury. The respondent admitted liability, subject to a small reduction for contributory negligence, and the matter went to trial on the assessment of damages. The respondent accepted that Mr. Smithurst had suffered injury as a result of its negligence in providing him with a defective van and for that reason liability was admitted; the only dispute was about whether he would have suffered a similar injury in the future and if so when. That was a question on which the medical experts were divided: Mr. Smithurst's expert, Mr. Carew, said in his report that there was no reason to expect that he would have suffered a massive prolapse with similar consequences at any time in the future; the respondent's expert, Mr. Wilson-MacDonald, thought that he was likely to suffer a similar prolapse with much the same consequences within two years. Each of the experts explained their positions somewhat more fully in the course of their oral evidence, to some of which I shall refer a little later. Because the determination of that question was liable to have a significant effect on the award of damages, it was thought sensible to try it first before moving to other aspects of the assessment.
6. Before the judge Mr. Sanderson submitted that Mr. Smithurst was entitled to recover in full for all future loss, but that if the judge thought that there was any significant risk that he would have suffered a similar injury in the future, the right course was to assess that risk and reduce his damages by an amount appropriate to reflect it. In support of his argument he relied on various authorities including Mallett v McMonagle [1970] A.C. 166, Davies v Taylor [1974] A.C. 207 and Gregg v Scott [2005] UKHL 2, [2005] A.C. 177. Mr. Withington submitted on behalf of the respondent that since the issue was one of causation it had to be determined on the balance of probabilities. He distinguished the authorities relied on by Mr. Sanderson on the grounds that they were concerned with the assessment of damages, not with causation. He therefore submitted that if the judge accepted Mr. Wilson-MacDonald's evidence, damages should be assessed on the basis that the accident had accelerated Mr. Smithurst's condition by two years.
7. The judge preferred the respondent's arguments. He said:

"14. . . . the central issue for the court is whether or not the claimant's loss of [sic] injury would have occurred but for the admitted breach of duty by the defendant. In my judgment the court is dealing with the issue of causation and the 'but for' test is applicable. In those circumstances the issue in my judgment falls to be determined on the usual standard of proof, namely, the balance of probabilities.

15. The case at this stage, in my judgment, is essentially one of causation, as opposed to an assessment of damages, which will have to be dealt with later . . . I agree with Mr. Withington that to apply some loss of chance analysis would be well nigh impossible in the present case, not least because neither expert was asked to give any evidence about it. I consider therefore the issue falls to be determined on the usual standard of proof, namely, the balance of probabilities."

8. The judge then reviewed the expert evidence at some length. He preferred the evidence of Mr. Wilson-MacDonald, who had rather greater experience of this kind of injury than Mr. Carew, and found that Mr. Smithurst was likely to have suffered a massive prolapse with similar consequences within two years. That is the basis on which the assessment of damages will proceed, subject to the outcome of the appeal.
9. At one stage it appeared to be Mr. Smithurst's case that, where there is a risk that a claimant would have developed the condition from which he is suffering at some time in the future quite apart from the defendant's wrongdoing, the judge must always evaluate the risk of that occurring (what might be described as an "assessment of risk" approach) and is not entitled simply to find that it would have occurred after a given period of time (what is sometimes described as the "acceleration" approach). It is not surprising, therefore, that the respondent included in the authorities on which it relied the decision of this court in Kenth v Heimdale Hotel Investments Ltd [2001] EWCA Civ 1283 (unreported), in which the acceleration approach was approved. It soon became apparent, however, that Mr. Sanderson did not contend that the acceleration process is never appropriate, simply that it was not an appropriate approach in this case in the light of the evidence before the court and the way in which the case had been argued.
10. Before turning to the authorities it is necessary to remind oneself of the important distinction in cases of this kind between proof of damage and assessment of damages. Damage is an essential element of the cause of action in negligence and therefore, as part of establishing liability on the part of the defendant, the claimant must prove on the balance of probabilities that the defendant's act or omission caused the harm in respect of which he claims. If he fails to do so, his claim will fail: see, for example, Hotson East Berkshire Area Health Authority [1987] AC 750. It is to be contrasted with the assessment of damages, which involves determining the extent of the loss suffered by the claimant, a distinction which Lord Hoffmann was at pains to emphasise in paragraphs 67-69 of his speech in Gregg v Scott. That may involve an enquiry into what would have happened, either in the past or in the future, if the defendant had not caused harm to the claimant and may require the court to assess the chances that one or more particular events would or would not have occurred. In one sense the issue can be characterised as one of causation, but not causation in the sense of proving that the respondent's breach of duty was the cause of the injury. It is usually. and I think preferably, treated as an aspect of the assessment of damages. It calls for a different approach because the nature of the enquiry is different.
11. In the present case it was not in dispute that Mr. Smithurst had suffered injury as a result of a breach of duty on the part of the respondent; the only remaining question was how great a loss had he suffered as a result. In Mallett v McMonagle Lord Diplock described the approach of the court when assessing damages. He said at page 176:

"The role of the court in making an assessment of damages which depends upon its view as to what will be and what would have been is to be contrasted with its ordinary function in civil actions of determining what was. In determining what did happen in the past a 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 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 a 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."

12. In Davies v Taylor the plaintiff, who was making a claim under the Fatal Accidents Acts, was estranged from her husband. A question arose whether she might have returned to live with him at some time in the future and so be dependent on him. Lord Reid said at pages 212H-213C:

"When the question is whether a certain thing is or is not true - whether a certain event did or did not happen - then the court must decide one way or the other. There is no question of chance or probability. Either it did or it did not happen. But the standard of civil proof is a balance of probabilities. If the evidence shows a balance in favour of it having happened then it is proved that it did in fact happen.

But here we are not and could not be seeking a decision either that the wife would or that she would not have returned to her husband. You can prove that a past event happened, but you cannot prove that a future event will happen 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 per cent.: 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 per cent. and a probability of 49 per cent."

13. In the present case I think it is clear that the judge wrongly treated the question he had to decide as one of causation in the sense of proof that the respondent's breach of duty had caused Mr. Smithurst's injury. That was how the case had been argued by the respondent, which sought to distinguish the cases of Mallett v McMonagle and Davies v Taylor on the grounds that they were concerned with the assessment of damages, and the judge expressly preferred the respondent's argument. Indeed, as appears from paragraph 15 of his judgment, to which I have referred, the judge said that the case was one of causation and that the assessment of damages would have to be dealt with later. He therefore applied what he described as the 'but for' test which he regarded (correctly) as the appropriate test for determining causation. In support of his approach he relied on the decision of this court in Breeze v Ahmed [2005] EWCA Civ 223, [2005] All E.R. (D) 134, a case which was concerned with the need to establish a causative link between the defendant's breach of duty and the claimant's injury.
14. In Kenth v Heimdale Hotel Investments Ltd the claimant brought proceedings seeking damages for personal injury suffered while working as a chambermaid at the defendant's hotel. She obtained summary judgment with damages to be assessed. The claimant's injury consisted of a prolapsed disc which she said had caused her psychiatric illness and severe chronic back and leg pain. The judge found that she would have suffered similar symptoms sooner or later in any event because of a pre-existing organic condition which rendered her vulnerable to a disc prolapse. He found that the accident had merely accelerated the onset of her symptoms by five years and awarded her damages limited to a period of five years following it. The case has obvious similarities to the present. Indeed, as in this case, counsel for the claimant argued that the judge's approach was wrong in principle and that the proper course was to assess the risk that she would have suffered a similar prolapse at some indeterminate time in the future. The judge was wrong, it was said, to adopt a 'cut-off' point of five years unless it was virtually certain that the claimant would suffer similar symptoms within that time.
15. On the basis of the medical evidence the judge found in that case that the claimant could not have expected to go on working as a chambermaid for more than five years. He therefore treated it a case in which the defendant's breach of duty had accelerated a breakdown in the claimant's health by five years. Laws L.J., with whom Mummery L.J. and Sir Anthony Evans agreed, said:

"42. . . . the judge's approach here gave the Appellant the benefit of five years, assumed to be entirely trouble free, without this accident, and it is to be noted that an appropriate award of loss of earnings of 100 per cent basis was made in respect of the five years. Likewise, of course, the approach assumes it to be a certainty that but for the accident she would have had like troubles after five years.

43. The position here arrived at might perhaps coarsely be described as a swings and roundabout approach. What one cannot say is that it is, by reference to any principle, in some way less fair or just to the Appellant. Theoretically, indeed, the acceleration approach ought to produce the same result as Mr de Navarro's approach. In the event then I would accept the Respondent's submission summarised in counsel's skeleton argument, page 8, paragraph 10, that the notion of acceleration:

"This is simply a methodology of assessing the value of the Claimant's losses. It could have been expressed in terms of a chance if the medical evidence was presented in that form or if the medical witnesses had said that they did not know when symptoms would arise only that they would arise at some indeterminate time".

44. Before us this afternoon Mr Burton QC for the Respondents sought, in particular, to emphasise the passage on the next page and it is convenient to read it:

"None of the experts including the Claimant's expert sought to look at the matter in terms of a percentage chance that the Claimant would have had or avoided a similar accident and with similar sequelae. The Claimant's counsel never addressed the Judge as to what percentage ought to be the chance occurrence on the basis of the evidence yet now invites this court to do precisely that. The Judge can hardly be criticised for expressing his findings in the way that he did given the way in which the evidence was presented. It would have been wholly wrong for the Judge to express it in terms of a percentage chance given that this was not the way in which the evidence was canvassed."

45. It seems to me, on the particular facts here, that those submissions are correct. It is to be noted that the acceleration methodology has been used extremely commonly as cases corrected in Kemp, referred to by the Respondents, amply demonstrate. I hope I may be forgiven if I do not set them out. In the result, at the least the learned Deputy Judge was entitled to proceed as he did. This was, in truth, a case where an acceleration approach was entirely proper. One can readily imagine, if this or that aspect of the case had been fashioned somewhat differently, that a different approach might have been at least that appropriate, perhaps more appropriate. As always in these cases, and one must go on with the particular facts and the evidence that was given and in relation to those in my judgment, the approach here taken cannot be faulted."

16. Our attention was also drawn to the case of Hanks v Ministry of Defence [2007] EWHC 966 (QB) (unreported) in which Royce J. in the course of assessing damages did consider the risks that certain events would happen in the future and made different assessments in relation to different events relevant to different heads of loss. However, I do not think it follows that that is the only permissible method to adopt. The assessment of damages is to some extent inevitably imprecise; what is required is that the judge adopt a method of assessment that is fair to the claimant and takes proper account of the evidence before the court and the way in which the case was presented. Although in principle when considering what the future would have held for the claimant had he not been injured by the defendant the court should approach the matter by assessing the relevant risks or chances, that may call for a much more sophisticated enquiry than the court is equipped to perform. As Laws L.J. pointed out, in many cases the acceleration method, although less refined, will be fair to the claimant if it properly reflects the medical evidence. It is therefore necessary to consider the evidence before the court in this case and the way in which the arguments were developed.
17. The judge preferred the evidence of Mr. Wilson-MacDonald. In his report he had expressed the opinion that Mr. Smithurst was more at risk of sustaining a disc prolapse than the majority of the population and that on the balance of probabilities some other lifting or twisting event would have caused a similar disc prolapse over the following months, probably within two years. Having been initially cautious about the likely consequences, if a massive prolapse of a similar kind had occurred, he expressed the view that on the balance of probabilities it almost certainly would have been of a similar character.
18. In his evidence from the witness box Mr. Wilson-MacDonald dealt with this aspect of the matter more fully. Although one can point to certain inconsistencies in the way in which he expressed his views, he clearly considered that at the time of the accident Mr. Smithurst was at imminent risk of a massive prolapse. The following passages in his evidence-in-chief are significant:

"Q: To what extent do genetics play a part, if at all, as to whether a prolapse occurs?

A: Well, I think that genetics is actually more important in the development of degeneration, so there's a lot of evidence now that suggests that genetics are responsible to a large extent for the amount of degenerative change in your spine. Obviously the disc prolapse occurs in a disc which is already degenerate, so disc prolapse will be – is probably commoner by genetic association."

. . .

"Q: Can you just explain very briefly to His Honour why you felt that two years was the right sort of figure?

A: Well, we're not dealing with science, because there are no studies that give us this answer and I suppose that's one of the reasons why we disagree. I think that we know there was a degenerate disc, we know that a massive tear was either there already or happened that day and we know that a massive disc prolapse occurred.

His Honour Judge Curl: Yes.

A: If you believe that the insult was extreme and akin to dropping out of a window or coming off a motorbike, then I think the contention that the disc prolapse occurred purely as a result of that trauma is maybe reasonable. In my opinion the force applied to the disc was high, but not necessarily factors higher than the forces which would have occurred in his normal day to day life. And I think if the disc prolapse had not occurred on that day, it would have occurred soon afterwards and probably much sooner than two years after the event, but certainly within two years of the event."

19. He put it this way in the course of cross-examination:

"A: I'm saying the outcome would have been similar, because we can look at Mr. Smithurst's case retrospectively, and I don't see any strong reason why some other event would not have caused a tear in the disc and I don't see any particular reason why it should not have caused a very similar disc prolapse in the weeks and months that followed. And if the disc – if the tear was already there, again, I don't see why the outcome should have been very different."

. . .

"Q: . . . And so we're now looking in the question of hypothesis, as to what might happen in the future, and you think that probably he would have a disc prolapse in the future, yes?

A: Yes.

Q: But you'd accept that [it is] possible he wouldn't?

A: Yes. Very Unlikely.

Q: Very unlikely?

A; Yes. I think very unlikely he wasn't going to get a disc prolapse at some point in the future.

Q: Right O.K. You say as massive?

A: On the balance of probabilities."

20. Earlier in his evidence Mr. Wilson-MacDonald had agreed that the majority of patients who suffer a massive prolapse do not suffer a permanent neurological damage and that luck seems to play a part in that. When he was asked in re-examination about the chances that the outcome of any future prolapse would have been as serious as that suffered by Mr. Smithurst, the following exchange occurred:

"Q: You've also been asked on a number of occasions about luck.

A: Mm, Mm.

Q: O.K. In so far as luck is concerned, is luck in reference to the particular development of this particular prolapse, is it luck because he's just got a bad genetic make-up, what's the luck that you're referring to?

A: Luck is that you can have three different patients who have a scan that looks identical and one of them has serious neurological problems and the other two don't. So we can't always explain why one person has a neurological deficit and another one doesn't.

Q: So it's luck in comparison to a group as a whole, as opposed to him specifically?

A: Yes.

. . .

Q: . . . what's your view as to the percentage likelihood of Mr. Smithurst having the same symptoms as a result of a future prolapse which you anticipate would have happened?

A: Well, I'm anticipating the prolapse is going to be broadly similar, so on balance I can't think of any reason why the neurological effect of that is not going to be broadly similar."

21. It is true that in his report and at various points in his evidence Mr. Wilson-MacDonald expressed himself in terms of the balance of probabilities, even when speaking about the likelihood that Mr. Smithurst would have suffered a massive disc prolapse within about two years. However, taking his evidence as a whole I think it points clearly to the following conclusions:

(i) that Mr. Smithurst had a genetic predisposition to disc degeneration and that the disc at L5/S1 had already suffered a significant degree of degeneration;

(ii) that the forces needed to cause a massive prolapse of the kind that occurred on 16^th March 2006 were no greater than could be expected to be imposed on his lower spine in the course of his ordinary activities;

(iii) that although it was not possible to say with confidence when it would occur, Mr. Smithurst was liable to suffer a massive prolapse at any time, that is within a matter of days, weeks or months of the accident and almost certainly within a period of two years at the most;

(iv) that the nature of the degeneration was such that the prolapse itself, whenever it occurred, and its consequences would almost certainly have been the same.

22. It is accepted that the judge was entitled to prefer Mr. Wilson-MacDonald's evidence to that of Mr. Carew and in my view his evidence bears out the course that the judge took, albeit for the wrong reasons. It supports the conclusion that the chances of Mr. Smithurst's suffering a very similar injury in the future existed as from the moment of the accident and rose progressively to near certainty by the end of two years. A detailed evaluation of the chances that Mr. Smithurst would have suffered a similar injury at any given point in his working life might lead to a different award of damages, but that does not mean that it is wrong to adopt the acceleration approach. As I have already noted, this case is very similar to that of Kenth. Here, too, it may be said that the acceleration method would involve an element of swings and roundabouts, under which Mr. Smithurst would recover damages calculated at the full rate over two years but nothing thereafter, rather than damages calculated at a progressively diminishing rate over a longer period. I do not think that an excessively analytical approach to the assessment of damages is to be encouraged in cases of this kind and where the medical experts have not attempted to forecast in statistical terms the chances that a similar injury would have occurred at different times in the future the judge will not have been provided with the means to carry out a proper assessment of the risks involved. In those circumstances, provided the judge is careful to ensure that the cut-off date fairly reflects the medical evidence, the acceleration approach can in my view properly be adopted.
23. In the present case the judge mistakenly thought that he was dealing with a question of causation in the ordinary sense. He was wrong about that, but for the reasons I have given I think it is permissible nonetheless to adopt, as he did, an acceleration approach to the assessment of damages in this case (indeed, I doubt whether it is practicable to do anything else). In my view the judge's finding fairly reflects the opinion of the expert witness whose evidence he preferred. In those circumstances I would dismiss the appeal.

Lord Justice Rix:

24. I agree.

Sir Nicholas Wall P.:

25. I also agree.