England and Wales Court of Appeal (Civil Division) Decisions

IN THE SUPREME COURT OF JUDICATURE
COURT OF APPEAL (CIVIL DIVISION)
ON APPEAL FROM PRESTON COUNTY COURT
MR RECORDER HALLIWELL
6PR01342

		Royal Courts of Justice Strand, London, WC2A 2LL
		05/11/2008

Lady Justice Smith :

Introduction

1. This is an appeal from the order of Mr Recorder Halliwell, sitting in the Preston County Court on 11 March 2008. The claimant, Ms Donna Marie Hull, had alleged that she had been infected by the campylobacter bacterium as the result of her employers' breach of duty during the course of her employment as a turkey plucker. The recorder gave judgment for Ms Hull for £16,237.49. The employers now appeal against that order.

The factual background and the trial

2. At the material time in 2003, Mr and Mrs Sanderson ran a farm at Hutton near Preston. Mr Sanderson has since died. Each year before Christmas they took on extra labour to prepare turkeys for sale. On 15 December 2003, Ms Hull began work as a plucker. On 20 December she became ill and was soon diagnosed as suffering from campylobacter enteritis. She believed this to have resulted from her employment and, in March 2006, she commenced an action for damages. The particulars of claim alleged a number of statutory and common law breaches of duty, as a result of which she alleged she had been exposed to the bacteria and had developed the disease. The employers denied breach of duty and causation.
3. The claimant also alleged that the turkeys had been infected with the campylobacter bacterium as the result of eating contaminated food. However, during the hearing, that allegation was abandoned and the action proceeded on the basis that the employers had failed to protect Ms Hull from the risks of infection which were inherent in handling dead poultry.
4. The action came on for hearing on 6 December 2007. The recorder heard lay evidence about the working conditions and the health and safety arrangements. It emerged that Mr and Mrs Sanderson had been unaware of the risk of campylobacter infection and had not warned Ms Hull about it. They provided gloves and aprons. Ms Hull found that the gloves were too big for her very small hands. She noticed that Mr Sanderson and some other employees plucked turkeys without gloves. She spoke to Mr Sanderson about this and he told her that she could work without gloves if she preferred to. So from the third day, she worked without gloves.
5. The employers' case on liability was that the only effective means of reducing the risk of infection was regular and thorough hand washing. They had provided suitable facilities. Although they had not warned Ms Hull about the risks of the campylobacter bacterium, it was contended that all she needed to know was that she should obey the ordinary common sense rules of hygiene. She had worked in the catering industry in the past and was or should have been aware of such rules. Ms Hull said that she washed her hands at each break before eating or having a cigarette.
6. The recorder also heard expert witnesses: Mr M.R.Zeiderman, a Consultant Gastroenterologist and General Surgeon for Ms Hull and Mr David Joyce, a microbiologist, for the employers. There was a measure of agreement between them. They agreed that campylobacter bacteria are very commonly found in poultry but are also common in other circumstances, including animal excrement. The risks had been known of for some years and advice was available as to the precautions which should be taken. The experts also agreed that the only route by which the bacteria could have entered Ms Hull's body was by her mouth; it could not have entered through a cut or abrasion to the skin.
7. Ms Hull's case on that issue was that she should have been warned of the risk of infection if she were to touch her mouth while her hand might be contaminated. Mrs Sanderson agreed that no such warning had been given but her case was that it was common sense that one would not touch one's face while working with dead turkeys; Ms Hull should have known that.
8. The experts were asked to consider whether it was probable that Ms Hull had picked up the infection at work as opposed to elsewhere. Mr Zeiderman was of the view that she had probably picked it up at work. The incubation period was between 1 to 3 days; the respondent had worked from 15 to 20 December and became ill on 20 December. It would be a remarkable coincidence if she had picked up the infection elsewhere. Notwithstanding that element of coincidence, Mr Joyce felt unable to agree.

The first draft judgment

9. At the end of a commendably expeditious hearing, the recorder reserved his judgment. On 19 December 2007, he sent a draft judgment to the parties. In it he held that the employers had been negligent and had breached several statutory duties. These included a failure to provide suitable gloves and to tell Ms Hull to change them frequently and also a failure to warn Ms Hull of the risks of exposure to campylobacter bacteria from the turkeys and to advise her as to the precautions she should take to minimize the risk of infection. This should have included advice about not touching her face or mouth while her hands were contaminated. The recorder rejected the suggestion that Ms Hull had been contributorily negligent.
10. As to causation, the recorder first considered whether Ms Hull had contracted the infection at work or elsewhere. He held that, on the balance of probabilities, she had picked it up at work. He added that the most likely explanation for the infection was that, having handled parts of the turkey carrying the bacterium or touched contaminated items or materials with her hands, one of her hands came into contact with her mouth and she ingested the bacterium.
11. The recorder then turned to consider whether, but for the employers' negligence, Ms Hull would probably not have contracted the infection. He noted that the burden of proof lay on Ms Hull.
12. The recorder reviewed his findings of breach of duty, including the employers' failure to give proper advice. He asked himself whether that advice would have been effective. At paragraph 45, he noted that Ms Hull had not been asked hypothetically whether she would have heeded such advice. He considered that evidence on that issue was likely to be self-serving and of limited value. He continued:

"Had she been given such advice, no doubt she would have been more circumspect than she was. She would have been less willing to discard her gloves. Had she continued to wear gloves, she would have changed her gloves each day. Had she made a decision to discard the gloves, she might have been more circumspect in touching her face by hand. It is quite possible that she would also have been more circumspect generally in relation to the use of her hands, particularly after they had come into contact with contaminated items."

13. The recorder then observed that these thought processes 'involved a considerable amount of speculation'. He turned to consider all the ways in which Ms Hull might have come into contact with the bacteria. He thought it possible that she could have picked it up from a door handle or table or the draining board of the sink unit. He did not say whether such contact would have resulted from negligence or have been unavoidable. He thought that some risk would have arisen however circumspect Ms Hull had been. He observed that if she inadvertently touched her mouth with her hand while plucking a turkey, she would be exposed to a similar level of risk, whether her hand was gloved or not. In the end, he said that there was a real possibility that the respondent had become infected owing to the employers' breach of duty but he could not say on the balance of probabilities that she had been. He found in favour of the employers.

Submissions on receipt of the first draft judgment

14. Immediately on receipt of the draft judgment, Mr Douglas, counsel for Ms Hull, contacted the recorder and asked him to reconsider his holding on causation. He submitted that it was not possible for Ms Hull to satisfy the 'but for' test of causation. It should be sufficient for her to show that the employers' breach of duty had materially increased the risk of her contracting the infection. He apologised for his omission to address the point in his closing submission. He asked for the opportunity for both parties to put in detailed submissions.
15. The recorder's response was to suggest to both counsel that they should prepare further written submissions. A timetable was quickly agreed.
16. Mr Douglas submitted that the case fell within the principle expounded by the House of Lords in Fairchild v Glenhaven Funeral Services [2003] 1 AC 32, where the House of Lords had held that, in a case of mesothelioma, where it was impossible for a claimant to prove which of several employers who had all exposed him to asbestos dust had actually caused the disease, it was sufficient for the claimant to show that the employer's breach of duty had materially increased the risk of injury. He also cited McGhee v National Coal Board [1973] 1 WLR 1 where, he said, the House had held that, where difficulties of proof arose in a dermatitis case, it was sufficient for the claimant to prove that the defendant's breach of duty had materially increased the risk of injury.
17. Mr Douglas referred in particular to the speech in Fairchild of Lord Rodger of Earlsferry who, at paragraph 170, had set out the conditions which would have to be satisfied before causation could be proved by showing a material increase in risk. He submitted that each of those conditions was satisfied in the instant case.
18. Mr Simon Butler, counsel for the employers, responded in a full and careful written submission, contending, first, that the recorder should not entertain the new submissions and second, that this was not a case in which the 'but for' test of causation should be relaxed. The recorder had been correct to apply it as he had done in the draft judgment and it was clear that Ms Hull could not satisfy it.
19. The recorder was apparently of the view that the new submissions should be entertained.

The final judgment

20. On 10 January 2008, the recorder sent his revised judgment to the parties. He had been persuaded to change his mind. He repeated his conclusions relating to the 'but for' test and then accepted Mr Douglas's submission that the case fell within the Fairchild principle. He held that Ms Hull had established the causal link between breach of duty and injury by showing that the breaches of duty had materially increased the risk of infection. The recorder then assessed quantum of damage.

The Appeal to this Court

21. The appellant employers appeal on three grounds. The first two relate to the application of the Fairchild principle. The principle is an exception to the 'but for' rule of causation and the House of Lords often calls the principle 'the exception'. The third ground of appeal concerns the practice of asking a judge to reconsider the substance of his decision on receipt of a draft. I will deal with the third ground first.

Asking a judge to reconsider his decision

22. In recent years, the practice has grown up whereby judges send a draft of their judgments to counsel in advance of formal hand down. The purpose is to enable the parties to agree a form of order and to take instructions on any proposed appeal. The practice also provides an opportunity for counsel to advise the judge about any minor errors in the draft. However, there have been cases in which counsel has sought to use the receipt of the draft as an opportunity to reargue the case. In Darren Egan v Motor Services (Bath) Ltd [2007] EWCA Civ 2002, where the losing party before the judge below had sought to reargue the issues, I deprecated this practice and said that it should only be adopted in exceptional circumstances, of which I gave examples which were not intended to be exhaustive. More significantly, in Edwards v Environment Agency [2008] UKHL 22, where the losing party was unwise enough to seek to persuade the House of Lords to change its view on a range of points most of which had already been argued, Lord Hoffmann described the practice as an abuse. In that case, it certainly was.
23. In the present case, Mr Butler does not seek to argue that Mr Douglas acted improperly in inviting the recorder to reconsider the issue of causation; he submits only that the recorder should not have acceded to the request because the issue of material contribution to risk had not been pleaded or argued at the trial. Nor had it been raised with the experts. Mr Butler does not complain that he was denied the opportunity to deal with the issue. Nor has Mr Butler attempted to demonstrate that the failure to put the issue of material contribution to risk left any evidential gap which had to be filled before the recorder could properly consider the issue. His submission is just that, because the point was not taken properly at the hearing, the recorder should not have entertained it later.
24. Mr Douglas accepts that he had not pleaded the issue of causation as specifically as he now wishes. Nor had he dealt with it in closing submissions in the way in which he now puts his arguments. He frankly acknowledged that he had not foreseen that the recorder would deal with causation as he did. He thought that, at the hearing, the issue which exercised the parties' minds was whether Ms Hull could show, on the balance of probability, that she had picked up the infection at work rather than elsewhere. He had thought that, if she could, that would be an end to the matter. He had not thought that the recorder would be concerned about the possibility or probability that the infection might have been picked up at work but through a non-negligent mechanism. However, Mr Butler pointed out that he had raised that second issue in his closing submissions to the recorder. It was for Mr Douglas to raise and argue the issue of material contribution to risk, if he were going to rely on it. Mr Douglas, somewhat ruefully, accepted that he had not done so.
25. In my view, there was nothing inherently wrong with the Mr Douglas's request that the recorder should reconsider this specific issue. He had failed to argue a point that he now believed was vital to his client's case. His request was not an attempt to 'reargue' the issues which had already been argued and decided by the recorder; it was an admission that he had failed to raise what he now thought was a vital issue. Whether he was right about that is a different matter to which I will return. It appears to me that the recorder immediately thought that Mr Douglas's point was important and he was willing to reopen his decision. Mr Butler did not suggest that, if the point were to be taken, the pleadings would have to be amended. I do not think that the recorder should be criticised for taking the course he did.
26. It appears to me that, in the circumstances, the course that was taken was proper. If the recorder was of the view that a point had not been argued as it should have been, it was better that it should be dealt with as part of the trial process rather than being left over to feature in an appeal or, worse, in proceedings for professional negligence. I can see that some additional costs were incurred by counsel's failure to advance his arguments at the hearing and I confess that I am surprised that the recorder's order for costs did not reflect the effect of that oversight. But, that apart, I think that this was the best way out of the predicament as it appeared to the recorder. Mr Butler had a fair opportunity to put his case on the new point and I have little doubt that, if he had asked for an oral hearing, it would have been granted. The third ground of appeal fails.

The Fairchild Principle or Exception

27. The real substance of Mr Butler's complaint is that the recorder was wrong in his second judgment and right the first time. The case was not one of those where the Fairchild principle was capable of application. The recorder had been right the first time to hold that this was a case to be decided by application of the 'but for' rule. He had done so and had decided that causation was not made out. This court should say that that conclusion could not be interfered with.
28. Mr Butler submitted that the recorder had extended the Fairchild principle to another disease or condition in circumstances where he should not have done so. Lord Nicholls of Birkenhead said at paragraph 43 of Fairchild:

"Considerable restraint is called for in any relaxation of the threshold 'but for' test of causal connection."

Also, in Barker v Corus UK Ltd [2006] AC 572; [2006] UKHL 20 where the House affirmed that there were circumstances in which a claimant would not need to satisfy the 'but for' rule of causation but could rely merely on showing a material increase in risk, Lord Hoffmann said, at paragraph 5:

"…the opinions of all of your Lordships who heard Fairchild expressed concern, in varying degrees that the new exception should not be allowed to swallow up the rule. It is only natural that, the dyke having been breached, the pressure of a sea of claimants should try to enlarge the gap."

However, Mr Butler, also very fairly reminded the court of Lord Bingham's acknowledgment at paragraph 34 of Fairchild that:

"It would be unrealistic to suppose that the principle affirmed will not over time be the subject of incremental and analogical development. Cases seeking to develop the principle must be decided when and as they arise."

29. Mr Butler submitted that the courts have already considered other types of situation and have decided that the Fairchild principle (or the similar preceding principle to be derived from McGhee) is to be narrowly confined. He drew attention to Wilsher v Essex Area Health Authority [1988] AC 32 and submitted that, in the context of a clinical negligence case, the House had held that the McGhee principle did not apply. I interpose to say that I do not think that the House held that the principle in McGhee would never apply in a clinical negligence case. They held that it did not apply on the facts of that case. The defendants had negligently allowed the oxygen levels in the claimant's blood to rise to an inappropriate level giving rise to an increased risk that he might develop retrolental fibroplasia. But excessive oxygen in the blood was only one of five possible agencies or mechanisms in play, any of which might have been the cause of the condition in the claimant. The problem was that the claimant could not show which agency or mechanism had probably caused the condition. The House of Lords held that it was not enough that the claimant could show a material increase in the risk from one cause where there were other potential causes in play but, as I understand the decision, they did not say that the principle in McGhee could never apply in a case of clinical negligence.
30. Mr Butler also referred to Clough v First Choice Holidays and Flights Limited [2006] EWCA Civ 15 and submitted that this was authority for the proposition that the Fairchild exception does not apply in single incident accidents. In that case the claimant was injured when he fell while walking along a wall at the side of a paddling pool. The owners of the pool should have painted the wall with non-slip paint; by that failure they had increased the risk of the claimant slipping. Other causative factors were in play; the claimant's feet were wet and he had drunk a good deal of alcohol. The judge rejected the claim; he applied the 'but for' test and also said that it would be sufficient if the claimant showed that the absence of non-slip paint had materially contributed to his fall. But he held that the breach of duty 'lacked causative potency'; the accident would probably have happened irrespective of the use of non-slip paint. The judge considered the 'material contribution to risk' argument but held that it did not apply in that case.
31. On appeal, the appellant argued that the judge should have found liability on the basis that the failure to use non-slip paint had materially increased the risk of a fall. The Court of Appeal dismissed the appeal saying, in effect, that on the facts as found, the judge had been entitled to reach his conclusion. Sir Igor Judge, then President of the Queen's Bench Division admitted that he had found the point a difficult one. I would accept that, if any principle is to be derived from this case, it is that which Mr Butler contends for, namely that the Fairchild exception will have no application in a personal injury claim arising from a single incident. However, for my own part, I would say that the Court did no more than to hold that, on the facts, the judge had been entitled to reach his conclusion.
32. Mr Butler summarised this part of his submission by asking, rhetorically, where is the line to be drawn beyond which the Fairchild exception does not apply? He answered that it is to be drawn so as to exclude this case.
33. Mr Douglas submitted that this case does not entail an extension of the Fairchild principle, only its application to different facts. He submitted that the facts of this case satisfy all the conditions laid down by Lord Rodger of Earlsferry at paragraph 170 of Fairchild. He accepted that the precise limits of the principle have not yet been established. It was clear that the principle was not limited to cases of mesothelioma. In McGhee, the House of Lords had held that the claimant could succeed even though he could not satisfy the 'but for' test but only show that the negligent prolongation of the contact between his body and the brick dust had increased the risk of developing dermatitis. In Fairchild, the House acknowledged that McGhee had been an earlier application of the principle now enunciated. If the exception covers dermatitis, why not also to campylobacter enteritis or indeed any other medical condition where the circumstances satisfy Lord Rodger's conditions?
34. I for my part would accept that great caution is required before any development of the Fairchild exception should be allowed. It was for that reason that I granted permission to appeal in this case. I thought that this court should scrutinise the application of the exception to the facts of this case.
35. Mr Butler did not seek to argue that Lord Rodger's set of conditions were not an appropriate guide to the scope of the Fairchild exception. While noting that not all their Lordships expressed themselves in the same way when discussing the scope the exception, Mr Butler was content to argue that, on the facts of this case, in two respects the conditions were not satisfied.
36. First, Mr Butler submitted that the respondent had not shown that it was impossible for her, on the present state of scientific knowledge, to satisfy the 'but for' test by showing how her injury had been caused. She claimed that she could not do so, but in fact she had done so. It was agreed evidence that the only way she could have become infected was by oral ingestion. The recorder had accepted that she had probably touched her mouth with her hand while it was contaminated. She had also satisfied the judge that she had picked up the infection at work rather than elsewhere. There was nothing that scientific knowledge prevented her from proving.
37. On that point, Mr Douglas submitted that the problem of causation had arisen because the respondent could not show whether the infection had got onto her hand (and thence to her mouth) as the result of one of the breaches of duty or as the result of some circumstance which did not result from a breach of duty. She could not show by what specific route her hand had become infected so as to be transmitted to her mouth when she touched it. It was impossible for her to do so. Mr Zeiderman had said that the infection had probably been picked up at work, although he could not be sure. Mr Joyce felt unable to say. Although they had not been asked by what specific route the infection had been picked up, it was implicit in their evidence that they would not have been able to say, for example, whether the contamination of her hand had arisen from direct contact with an infected turkey or by indirect transmission from the turkey to a door handle or table or draining board and thence to her hand. This, submitted Mr Douglas was indeed a case where the respondent could not possibly meet the requirements of the 'but for' test.
38. Mr Butler also argued that the recorder had been wrong in his approach to another of Lord Rodger's conditions. His second ground of appeal asserted that the recorder had been wrong to conclude that the failure to wear gloves had materially increased the risk of the respondent contracting the infection. As I understand it, he was referring to the employers' negligence in sanctioning Ms Hull's decision to abandon the use of gloves. However, that was not the recorder's holding. At paragraph 53 of his judgment, the recorder said:

"…I am satisfied that the (employers) did commit breaches of their statutory duties to the claimant and they failed to take reasonable care to reduce the reasonably foreseeable risks to her health. In doing so, they materially increased the risk of her contracting the campylobacter bacterium."

39. It is clear, in my view, that the recorder did not single out the failure to use gloves as the sole cause of the material increase in risk of infection; he was saying that all the breaches of statutory duty and acts of negligence that he had previously identified had materially increased the risk. I do not understand Mr Butler to have argued that that conclusion was not justified; indeed, it seems to me to follow as a matter of common sense. In particular, it seems to me that the employers' negligence in failing to warn the respondent of the risks of infection being transmitted via her mouth and to advise her to be careful not to touch her mouth until her hands had been thoroughly cleaned must have materially increased the risk of infection. I say that, in the light of the agreed evidence that the only method of entry was via the mouth and the recorder's finding that the respondent would have been more circumspect if she had known of the risks. So, I reject, without further discussion, the suggestion that the recorder erred in finding that the breaches of duty had materially increased the risk of infection.

Discussion

40. As I have said, the recorder was invited to consider whether this case fell within the scope of the Fairchild principle by reference to the six conditions laid down by Lord Rodger. Mr Butler has not suggested that that approach was wrong. However, it seems to me important to examine first whether the other members of the House agreed with those conditions and also whether they were modified in Barker. For that reason, I think it appropriate to examine what each member of House said in Fairchild about the scope of the exception and what the differently constituted House said in Barker.
41. In Fairchild, their Lordships did not speak with one voice on the scope of the exception. At paragraph 2, Lord Bingham of Cornhill set out six conditions which might justify the relaxation of the 'but for' rule of causation. He said:

"If (1) C was employed at different times and for differing periods both by A and B and (2) A and B were both subject to a duty to take reasonable care or to take all practicable measure to prevent C inhaling asbestos dust because of the known risk that asbestos dust (if inhaled) might cause a mesothelioma and (3) both A and B were in breach of that duty in relation to C during the periods of C's employment by each of them with the result that during both periods C inhaled excessive quantities of asbestos dust and (4) C is found to be suffering from a mesothelioma and (5) any cause of C's mesothelioma other than the inhalation of asbestos at work can be effectively discounted, but (6) C cannot (because of the current limits of human science) prove, on the balance of probabilities, that his mesothelioma was the result of his inhaling asbestos dust during his employment by A or during his employment by B or during his employment by A and B taken together, is C entitled to recover damages against either A or B or both A and B?

42. At paragraph 34, Lord Bingham held that, if those conditions were satisfied, C should recover from both A and B. But, he said, this relaxation of the 'but for' rule should be allowed only in those circumstances; any attempt at development would have to be decided as it arose. He considered that this result was consistent with principle and authority; it would be just and would accord with common sense. In formulating his six conditions by reference to mesothelioma caused by asbestos exposure, Lord Bingham appeared to be confining the exception, at least for the time being, to cases of mesothelioma. However, he cannot have so intended because, at paragraph 35, he accepted that McGhee, a case of dermatitis, was an application of the same exception as he had applied in Fairchild, or was at least analogous to it. I would conclude therefore that Lord Bingham's conditions were not intended to exclude the application of the exception to other conditions and circumstances; but he was declining to lay down any general principles and was deciding only the cases before him.
43. Lord Nicholls of Birkenhead did not seek to define the scope of the exception by reference to a list of conditions. He discussed the need for relaxation of the 'but for' rule where justice and fairness demanded it and observed that the balancing exercise between the rights of the parties involves a value judgment. He considered that the circumstances in which relaxation would be allowed would be exceptional. The examples he specifically discussed were the mesothelioma cases and the case of a claimant who had been shot and who sued two hunters, both of whom had fired their guns and might have hit the claimant but the claimant could not prove which shot had hit him. It was clear that an essential element for the extension was to be the impossibility for the claimant to prove enough to satisfy the 'but for' test. I observe in passing that, nowadays, it might well be possible, with the aid of a ballistics expert, to prove which gun had fired the shot which struck the claimant. But Lord Nicholls was clear that impossibility of proof is a requirement before the exception can apply. Mere difficulty of proof would not be enough: see paragraph 43. Restraint must be exercised in allowing any relaxation because of the potential unfairness to defendants. Policy questions would loom large when a court has to decide whether the difficulties confronting the claimant justify the court in taking the exceptional course. Lord Nicholls was not prepared to be more specific than that.
44. Lord Hoffmann, at paragraph 56, said:

"The concepts of fairness, justice and reason underlie the rules which state the causal requirements of liability for a particular form of conduct (or non-causal limits on that liability) just as much as they underlie the rules which determine that conduct to be tortious. And the two are inextricably linked together: the purpose of the causal requirement rules is to produce a just result by delimiting the scope of the liability in a way which relates to the reasons why liability for the conduct in question exists in the first place."

Then, at paragraph 60, he said that the problem was to formulate a just and fair rule, based on principle and not merely on the deserving nature of the claimant's case. At paragraph 61 he analysed the significant features of the current cases as follows:

"61. … First we are dealing with a duty specifically intended to protect employees against being unnecessarily exposed to the risk of (among other things) a particular disease. Secondly, the duty is one intended to create a civil right to compensation for injury relevantly connected with its breach. Thirdly, it is established that the greater the exposure to asbestos, the greater the risk of contracting that disease. Fourthly, except in the case in which there has been only one significant exposure to asbestos, medical science cannot prove whose asbestos is more likely than not to have produced the cell mutation which caused the disease. Fifthly, the employee has contracted the disease against which he should have been protected.

62. In these circumstances, a rule requiring proof of a link between the defendant's asbestos and the claimant's disease would, with the arbitrary exception of single-employer cases, empty the duty of content. If liability depends upon proof that the conduct of the defendant was a necessary condition of the injury it cannot effectively exist."

45. Lord Hoffmann concluded that, in cases which exhibit the five features he had mentioned, the 'but for' rule of causation should be relaxed. It will be seen that this analysis was by reference to mesothelioma cases but, at paragraphs 64 to 66 he analysed the facts of McGhee, by reference to his five factors and found them to be present. In Barker, Lord Hoffmann was to conclude that McGhee was an 'avant la lettre' application of the Fairchild exception. That being so, it is clear that he envisaged that the exception will not be limited to cases of mesothelioma. It seems to me that Lord Hoffmann has provided, in his five conditions, valuable guidance as to when the Fairchild exception might properly be applied to other diseases and conditions.
46. Lord Hutton did not agree with the analysis of the issue as propounded by Lords Bingham, Nicholls and Hoffmann although he too thought that the appeal should be allowed. At paragraph 108, he said that an inference of causation should be drawn in:

"cases such as the present ones where the claimant can prove that the employer's breach of duty materially increased the risk of him contracting a particular disease and the disease occurred, but where in the state of medical knowledge he is unable to prove by medical evidence that the breach was a cause of the disease."

47. Finally, Lord Rodger of Earlsferry adopted Lord Hutton's analysis but also sought to set out the conditions which would be necessary before an inference of causation should be drawn. At paragraph 170, he said:

"First, the principle is designed to resolve the difficulty that arises where it is inherently impossible for the claimant to prove exactly how his injury was caused. It applies, therefore where the claimant has proved all that he possibly can, but the causal link could only ever be established by scientific investigation and the current state of the relevant science leaves it uncertain exactly how the injury was caused and, so, who caused it. McGhee and the present cases are examples. Secondly, part of the underlying rationale of the principle is that the defendant's wrongdoing has materially increased the risk that the claimant will suffer injury. It is therefore essential not just that the defendant's conduct created a material risk of injury to a class of persons but that it actually created a material risk of injury to the claimant himself. Thirdly, it follows that the defendant's conduct must have been capable of causing the claimant's injury. Fourthly, the claimant must prove that his injury was caused by the eventuation of the kind of risk created by the defendant's wrongdoing. In McGhee, for instance, the risk created by the defendant's failure was that the pursuer would develop dermatitis due to brick dust on his skin and he proved that he developed dermatitis due to brick dust on his skin. By contrast, the principle does not apply where the claimant has merely proved that his injury could have been caused by a number of different events, only one of which is the eventuation of the risk created by the defendant's wrongful act or omission. Wilsher is an example. Fifthly, this will usually mean that the claimant must prove that his injury was caused, if not by exactly the same agency as was involved in the defendant's wrongdoing, at least by an agency that operated in substantially the same way. A possible example would be where a workman suffered injury from exposure to dusts coming from two sources, the dusts being particular of different substances each of which however could have caused his injury in the same way. Sixthly, the principle applies where the other possible source of the claimant's injury is a similar, but lawful, act or omission of the same defendant. I reserve my opinion as to whether the principle applies where the other possible source of injury is a similar but lawful act or omission of someone else or a natural occurrence."

48. In Barker, at paragraph 97, Lord Rodger accepted that his sixth condition had been too narrowly formulated and held that the principle did apply where the other possible source of injury is a similar but lawful act or omission of the defendant or of someone else or a natural occurrence. Lord Hoffmann was of the same view. At paragraph 17, Lord Hoffmann said:

"It should not therefore matter whether the person who caused the non-tortious exposure happened also to have caused a tortious exposure. The purpose of the Fairchild exception is to provide a cause of action against a defendant who has materially increased the risk that the claimant will suffer damage and may have caused that damage but cannot be proved to have done so because it is impossible to show, on a balance of probability, that some other exposure to the same risk may not have caused it instead. For this purpose it should be irrelevant whether the other exposure was tortious or non-tortious, by natural causes or human agency or by the claimant himself. "

Thus, both Lord Hoffmann and Lord Rodger were agreed that Lord Rodger's sixth condition had not been correctly stated in Fairchild. Indeed it seems to me that it has disappeared. It is necessary to identify the 'other exposure' which might have been the cause of the injury but it does not matter whether that other exposure was tortious or who was responsible for it.

49. At paragraph 24 of Barker, Lord Hoffmann adopted Lord Rodger's fifth condition when he said:

"In my opinion, it is an essential condition for the operation of the exception that the impossibility of proving that the defendant caused the damage arises out the existence of another potential causative agent which operated in the same way. It may have been different in some causally irrelevant respect, as in Lord Rodger's example of the different kinds of dust, but the mechanism by which it caused the damage, whatever it was, must have been the same."

50. In my view, so long as it is remembered that Lord Rodger's sixth condition is no longer applicable, his conditions (as amended) are a useful guide to the scope of the exception. I have undertaken this exercise because it appears from Mr Douglas's skeleton argument on the Fairchild issue that his summary of the conditions to be satisfied did not quite accurately reflect the modified views expressed by Lord Hoffmann and Lord Rodger in Barker. Having said that, I do not think that the differences are crucial in this case.
51. I turn to consider whether these conditions were satisfied in the instant case. The recorder held that they were although he did not expressly deal with each one. He preferred to take as his guide the statement from Lord Hoffmann's speech in Barker which I have cited above. He then said:

"In my judgment, the present case falls squarely within the Fairchild principle. The duties of the Partnership to take reasonable care to reduce, as far as practicable, the risks to the Claimant's health arising from her employment and her relevant statutory duties …. required them to protect her from the risk associated with the campylobacter bacterium. The single agency or mechanism through which the bacterium was spread was the contaminated turkey albeit that she could have been exposed to the bacterium at her place of work in a number of ways. For reasons that I have already given, I am satisfied that the partnership did commit breaches of their statutory duties to the claimant and they failed to take reasonable care to reduce the reasonably foreseeable risks to her health. In doing so, they materially increased the risk of contracting the campylobacter bacterium. Whilst it is not possible for the claimant to satisfy the 'but for' test I am thus satisfied that she is entitled to succeed under the Fairchild principle."

52. I regret to say that I do not think that the recorder has there analysed how the facts of this case can be brought within the Fairchild exception. He has merely stated that he is satisfied that it can be. He has said that the breaches of duty increased the risk that Ms Hull would contract the infection. I have already said that that seems to me to be unarguably correct. But it is trite law that that alone is not sufficient to satisfy the test of causation. Nor is it enough to bring the case within the Fairchild exception. Ms Hull must show that, on the facts of this case, there was some other exposure which could have been a potential cause of the injury and that it was scientifically impossible for her to show which exposure caused the injury. The recorder's approach to that issue was to observe that Ms Hull could not show how she had been infected; there were several ways in which she could have come into contact with the bacterium. In my judgment, that is not sufficient to bring the case within the exception.
53. I consider that it would be useful to apply Lord Rodger's conditions to the facts of this case. First, the claimant must show that it is inherently impossible for the claimant to prove exactly how his injury was caused. It must be impossible because of the current state of scientific knowledge. It is at this hurdle that Mr Butler alleges that Ms Hull fails. Second, the defendant's conduct must have materially increased the risk of injury to the claimant. I have already said that I consider that that condition is satisfied in this case. Third, the defendant's conduct must have been capable of causing the claimant's injury; in the present case it clearly was. Fourth, the claimant has to show that the injury was caused by the eventuation of the kind of risk created by the defendant's wrongdoing. In this case, it was; the kind of risk created was the risk of contracting bacterial infection and that was the risk that eventuated. Fifth, the injury must be caused by the same agency as was involved in the defendant's wrongdoing (or an agency which operates in a similar way). Here the same agency was involved, namely the campylobacter bacteria.
54. Thus the problem is that identified by Mr Butler, whether Ms Hull can show that there was another potential cause of her injury besides the employers' failure to warn her about the bacteria and to provide her with suitable protective clothing. Having shown what that other potential cause was, Ms Hull would also have to show that it was impossible for her, on the present state of scientific knowledge, to show which exposure has caused the injury.
55. It seems to me that the recorder has fallen into error because he has not properly analysed the facts relating to negligence and causation. On his findings, it was established that some of the turkeys were infected but that that had occurred without negligence on the part of the employers. Therefore the fact that Ms Hull's hands could very easily have become contaminated while she was plucking the turkeys was not due to the employers' negligence. That was so, whether or not she wore gloves. It was also possible that she might have picked up the infection on her hands by touching an infected surface, such as a door handle, table or sink unit. The recorder made no finding as to whether it was negligent of the employers to have permitted that to happen; indeed he observed that the premises were generally clean which suggests that he did not find negligence in that regard. Thus it appears to me that, whether Ms Hull got the infection on her hands directly from a turkey or indirectly from a surface which had become contaminated, the presence of the infection on her hands could not be said to have been due to the employers' negligence. So this is not a case in which we have one means of hand contamination which is tortious and one which is not.
56. We know the cause of Ms Hull's injury. It was that she transferred some bacteria from her hands to her mouth. The real question was or should have been to ask how that could have happened and then to consider whether any or all of the possible methods of transfer resulted from breach of duty.
57. The first possibility is that Ms Hull might have inadvertently touched her hand to her mouth while working with the turkeys. Would she have done that, on the balance of probabilities, if she had been properly warned as to the risks of the bacteria? The recorder made no definite finding as to that although he said that, if properly advised, she would have been more circumspect and he also said that it was 'possible that she would have been more circumspect generally in relation to the use of her hands'. That implies that the failure to warn had increased the risk of her touching her mouth with her hand but if the recorder had made a finding on the balance of probabilities that she would have heeded the warning, it would have been open to him to hold that the effect of that failure (with or without other failures to which I will come) was to cause the injury or make a material contribution to it. But there was no such finding.
58. The second possibility is that Ms Hull touched her mouth with her infected hand while eating, drinking or smoking. That would have taken place after work had finished or during a break. Why was her hand infected at that stage? It seems obvious that, if Ms Hull had worn gloves while plucking, the risk of the skin of her hands being contaminated would have been very much reduced so that, when she took a break and was about to eat or smoke, the likelihood of there being any bacteria on her hands would have been much reduced. So, it was open to the recorder to hold that, if she had been properly exhorted to use gloves and if suitable gloves had been provided, there would have been less likelihood of there being bacteria directly on her hands. The recorder must have thought that this failure had increased the risk of her hands being infected but he might well have gone further and said that that breach of duty had increased the risk so significantly that (with or without the effect of the other breaches mentioned above and below) it had probably caused or contributed to the injury.
59. The recorder accepted that Ms Hull always washed her hands before smoking and, by implication from the recorder's finding that she had not been contributorily negligent, I think he must also have found that she washed her hands before eating or drinking. There is a possibility that the transfer took place because Ms Hull did not wash her hands thoroughly enough before eating or smoking. The employers' negligence could have been causative in that event as, if she had been properly advised, Ms Hull might have taken more care over washing. But there is no specific finding of fact that she probably would have washed more thoroughly if she had been aware of the risks.
60. Another possible method of transfer was that, even though she cleaned her hands properly when she stopped work, Ms Hull touched an infected surface and soon afterwards touched her mouth while eating drinking or smoking. It seems to me that that could have occurred however well she had been warned and advised. However, the recorder did not attempt to assess whether, in his judgment, that seemed the more likely means of infection and transfer than any of the other possible means.
61. It seems to me that the recorder's difficulties in reaching a conclusion on causation were created not by any impossibility of proof but by his failure to make crucial findings of fact and to exercise his judgment as to the probabilities as to what happened. I accept that it can be difficult for a judge to decide whether on the balance of probabilities a claimant would have heeded a warning. Often there is no direct evidence on which the judge can rely and he has to base his decision on his impression of the claimant as a personality. I accept also, that it can be difficult for a judge to make a value judgment about the causative potency of various factors in play. But if the findings of fact that I have outlined above had been made, the recorder would have been able to make a decision on the usual 'but for' basis.
62. If the recorder had held that, if properly warned, Ms Hull would have been careful not to touch her face while working, he might then have been able to say that she would probably not have done so although he might have recognised a small risk still remained that she would do so. If the recorder had accepted that, if warned, Ms Hull would not have discarded the gloves, he could then have held that it was unlikely that her hands would have been infected at break time, particularly if she washed them as she said she did. So, eating and smoking would have carried a much reduced, possibly even negligible risk of transferring infection to the mouth. Finally, he would have had to recognise that there was still some risk of contact from door handles etc that could not have been reduced or avoided by any amount of warning. If findings of this kind had been made, it would have been open to the recorder to hold that, on the balance of probabilities, Ms Hull would not have been infected.
63. The conclusion I am driven to is that this was not a case in which it was impossible for Ms Hull to prove causation. The crucial issues were not incapable of proof, as is a necessary feature if a case is to be brought within the Fairchild exception. Here it could be said that there were difficulties of proof but that is not enough.
64. Accordingly, I have come to the conclusion that the recorder was wrong to hold that the case fell within the Fairchild exception. It did not. The recorder should have dealt with this case as one where the burden on Ms Hull was to show that the employers' breach of duty had caused or materially contributed to the injury. It follows that the appellant's first ground of appeal is made out.
65. Mr Butler submitted that when the recorder applied the 'but for' rule, as I have now held he should have done, he reached the conclusion that causation was not made out. Therefore, that conclusion must stand and must determine the outcome of this appeal. With some reluctance, I have come to accept that submission. I confess that I am concerned that the recorder did not approach the issue correctly. It seems to me that his analysis of the facts relating to causation was muddled and incomplete. He failed to make clear findings about how Ms Hull would have reacted to appropriate warnings. He seems to have been very confused as to how the employers' negligence would have operated.
66. However, there is no respondent's notice and no cross-appeal before this court. In those circumstances, it is not open to this court to remit the case to the recorder for him to make the necessary findings of fact on which he could properly base his conclusion on causation.
67. For the reasons I have given, I would allow this appeal.

Lord Justice Scott Baker : I agree.

Lord Justice Tuckey : I also agree.