Neutral Citation Number: [2008] EWCA Civ 1068
Case No: B3/2007/2778
IN THE SUPREME COURT OF JUDICATURE
COURT OF APPEAL (CIVIL DIVISION)
ON APPEAL FROM QUEEN'S BENCH DIVISION
Mr Justice Mackay

Royal Courts of Justice
Strand, London, WC2A 2LL

Date: 08/10/2008
Before :

LORD JUSTICE WARD
LORD JUSTICE DYSON
and
LORD JUSTICE LLOYD
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Between :

	Ryan St George (a Patient suing by his Father and Litigation Friend David St George)	Claimant/ Respondent	
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	The Home Office	Defendant/Appellant	
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(Transcript of the Handed Down Judgment of
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Michael Kent QC & Andrew O'Connor (instructed by Treasury Solicitors) for the Appellant
David Pittaway QC & Jane Tracy Forster (instructed by Messrs Hodge, Jones & Allen) for the Respondent

Hearing dates: Tuesday 29 July and Wednesday 30 July 2008
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Judgment
Lord Justice Dyson:
Introduction
1.	The claimant, then aged 29, entered Brixton prison on 29 October 1997 to serve a 4 month sentence for theft.  He had been an abuser of alcohol and drugs since the age of 16.  He was seen on reception at the prison and said that he was an intravenous heroin user, that he drank heavily and had previously had withdrawal seizures.  He declined an opportunity to see a doctor and was allocated to what was described as an “ordinary location”. A health screen interview confirmed that he had epileptic fits that were under investigation, that the drugs he was currently using were intravenous heroin (which he had last used that day) and valium and that he drank five or six pints of alcohol a day.  He was assigned to ward 3 of the hospital wing of the prison which at that time was being used as an ordinary unit for the accommodation of category D prisoners.  This took the form of an open dormitory with some single beds and some bunk beds.  The prison officers remained in control of who slept in which bed and inmates were not allowed to switch beds or bunks at will.
2.	The claimant slept on a top bunk.  At about 18.00 hours on 3 November 1997, he suffered a seizure which, it was common ground, resulted from his withdrawal from alcohol and drugs.  The seizure caused him to fall from his top bunk a distance of 7 or 8 feet to the floor.  He suffered a head wound.  His fitting continued without remission so as to justify the agreed diagnosis of status epilepticus (“status”).  This is a condition of recurrent seizures without recovery of consciousness between them.  He was attended by Home Office nurses at about 18.10 hours and an ambulance crew at 18.57 hours.  He was taken by ambulance to King’s College Hospital where he arrived at 19.25 hours.  The fitting was brought under control at 19.45 hours, but CT and MRI scanning over the following days revealed progressive severe damage to the brain which was agreed to be global hypoxic ischaemic damage and which left the claimant very severely and permanently disabled.
3.	A preliminary issue was ordered to be tried as to whether the Home Office “was liable to the claimant by reason of the matters alleged in the Particulars of Claim and, if so, whether or not any of the injuries pleaded were caused thereby; if any such injuries were so caused, the extent of the same”.   
Summary of the judge’s conclusions
4.	In summary, the judge found as follows.   The Home Office were in breach of duty in (i) allocating the claimant to a top bunk when, to the knowledge of prison staff, he had a history of substance abuse and withdrawal seizure while in prison; (ii) not protecting his airway from obstruction between the time of his fall and the arrival of the ambulance crew and not administering oxygen to him during that time; and (iii) being responsible for various failures which combined to delay the claimant’s arrival at hospital until 19.25 hours. The judge found, however, that this delay did not contribute to his brain damage.
5.	There were two principal causation issues.  The first was whether, as was contended on behalf of the claimant, the head injury resulting from the fall caused the withdrawal seizure to develop into status, i.e. (to use Dr Reynolds’ word) “triggered” the status, or, as was contended on behalf of the Home Office, the status was a consequence of the withdrawal seizure alone.  The judge found in favour of the claimant on this issue (which has been referred to as “the trigger theory issue”).  The second causation issue was whether, as the claimant contended but the Home Office disputed, the hypoxic ischaemia was caused by airway obstruction and/or the failure to administer oxygen before the arrival of the ambulance.  The judge found in favour of the claimant on this issue too, holding that, but for these breaches of duty, the claimant would have made “what would amount to a full recovery, subject at worst to minimal or perhaps transient deficits”: see [48] of the judgment.
6.	The judge also found that there had been contributory negligence on the part of the claimant, the fault lying in his addiction to benzodiazepine and alcohol which was the result of his own lifestyle decisions.  He held that the damages, when assessed, should be reduced by 15% to reflect the claimant’s fault.
The issues on appeal
7.	The Home Office appeals on the grounds that the judge erred in (i) finding in favour of the claimant on the trigger theory; (ii) finding that the prison staff were in breach of duty in not protecting the claimant’s airway or administering oxygen between the time of the fall and the arrival of the ambulance crew; and (iii) finding that the failure to protect the claimant’s airway and administer oxygen caused the hypoxic ischaemia.  There is no challenge to the judge’s finding that the allocation of the claimant to a top bunk was a breach of duty.  Further, Mr Michael Kent QC accepts that, unless the judge’s decision on the trigger theory issue is set aside, the appeal must be dismissed.  This is because on that theory, but for the head injury caused by the fall, the withdrawal seizure would have been self-limiting, would not have progressed to status and could not, therefore, have caused the dreadful brain damage from which the claimant now suffers.  
8.	The claimant supports the judge’s reasoning on the issues raised by the claimant and cross-appeals on the ground that the judge should not have found any contributory negligence on the part of the claimant at all.  The contributory negligence issue is one on which, it seems, there is no direct previous authority.
9.	For the reasons that follow, I would uphold the judge’s decision on the trigger theory issue.  It is, therefore, unnecessary to consider whether the judge was right to find the prison staff failed to protect the claimant’s airway and administer oxygen and right to find that these breaches caused the hypoxic ischaemia.  For the same reason, it is not necessary to examine what the prison staff did and did not do during the period between 18.10 hours when the nurses arrived and 19.11 hours when the ambulance left the prison.   I can come straight to the trigger theory.
The trigger theory
10.	It was common ground that the “predominant cause” of the diffuse, generalised and bilateral cerebral and cerebellar atrophy (the brain damage) was systemic hypoxic ischaemia.  As Mr Kent points out, given the absence of evidence of any traumatic brain injury resulting from the claimant’s fall and the fact that it was common ground that he was suffering a withdrawal seizure before he fell, the claimant had the burden of proving that any of the disability flowing from the hypoxic ischaemic brain damage was caused by the breaches of duty alleged.  
11.	The trigger theory was advanced by Dr Reynolds, the neurologist called on behalf of the claimant and rejected by Professor Chadwick, the neurologist called on behalf of the Home Office.  Both were described by the judge as “immensely distinguished experts” who had a particular interest and experience in the neurology of epilepsy.  The judge found Dr Reynolds to be a “quietly confident witness”.  
12.	Dr Reynolds said that he thought that the claimant was experiencing an “ordinary” withdrawal seizure as he fell from the bunk to the ground and that the head injury that he sustained when he hit the ground caused him to go into status.  He said that status can be triggered by head injury, even one which (as in the present case) is relatively minor and leaves no radiological sign or trace.  In support of his opinion, Dr Reynolds said that he relied on (i) his own clinical experience; (ii) the fact that the claimant had suffered three withdrawal seizures in the past, but none had progressed to status; (iii) the fact that withdrawal seizures were common in prisons, and yet none of the witnesses had encountered status before; and (iv) references in the medical literature.  
13.	The judge found these reasons “compelling” and accepted the evidence of Dr Reynolds.  Mr Kent submits that the reasons were far from compelling and that the judge should have preferred the evidence of Professor Chadwick.  
14.	As regards Dr Reynolds’ clinical experience, Mr Kent submits that Dr Reynolds was unable to give any example of a case where a patient, who had started fitting, had progressed to status following a mild head injury suffered in the course of the initial seizure.  In fact, what Dr Reynolds had to say on the subject only emerged in re-examination.  The following exchange took place: 
“MR JUSTICE MACKAY: Any re-examination?
MR PITTAWAY: Can I just ask about one matter? Your own clinical experience, which you said that you have, concussions causing seizures and status epilepticus, how commonly have you observed first concussions and minor head injury causing seizures, immediate seizures?
DR REYNOLDS:  Oh, quite rarely, quite rarely. Maybe half a dozen times in my career.
MR PITTAWAY: And those have been seizures that have followed immediately on concussions or minor head injuries?
DR REYNOLDS: Yes. But usually in the context of something else, I mean for example in the context of anti-epileptic drug withdrawal.
MR PITTAWAY: Right. So where you’ve had - is that an underlying cause which is anti-epileptic drug withdrawal?
DR REYNOLDS: It would be a more important factor.
MR PITTAWAY: Right. And in that case then, has the concussion acted as a precipitating factor in your clinic experience?
DR REYNOLDS: Of the seizure, yes.
MR PITTAWAY: Yes. And what about status epilepticus?
DR REYNOLDS: I can only think of one example.
MR PITTAWAY: And again, has the concussion acted – 
DR REYNOLDS: As a trigger?
MR PITTAWAY: - as a trigger?
DR REYNOLDS: Yes.
MR PITTAWAY: Yes, thank you, Dr Reynolds”
15.	Mr Kent submits that the cases described by Dr Reynolds of patients with established epilepsy who were withdrawing from anti-epileptic drugs in whom a concussion appeared to have provoked seizure were irrelevant.  It seems that the single case to which Dr Reynolds made fleeting reference where the seizure provoked by concussion developed into status was a case similar to the others.  But fundamentally, Mr Kent submits that this evidence did not provide a basis for inferring that Dr Reynolds was referring to a case similar to the claimant’s, ie a patient who had started fitting and who progressed to status following a mild head injury suffered in the course of the initial seizure.  
16.	Mr Kent says that Dr Reynolds’ second and third reasons prove nothing. It was well established that status was a rare condition.  In his report, Dr Reynolds said that withdrawal seizures were “usually” self-limiting.  Mr Kent makes the point that by implication, therefore, Dr Reynolds accepted that they were not always self-limiting.  
17.	As regards the medical literature, Mr Kent submits that it does not bear the weight that Dr Reynolds placed upon it.  Dr Reynolds relied on a paper by Professor Dieter Janz entitled “Conditions and Causes of Status Epilepticus” published in 1961 in a journal called Epilepsia and on a textbook, Status Epilepticus, written by a well known neurologist, Dr Simon Shorvon.   The paper by Professor Janz is of particular importance.  It is necessary to examine this paper in some detail.
18.	 Professor Janz distinguishes between symptomatic and idiopathic epilepsy.  It is common ground that the claimant’s epilepsy fell into the former category.  Status is more prevalent in the former than the latter.  At page 173, the professor says this: 
“We agree with Hunter that status should not be considered as a natural symptom of epilepsy, inherent to the underlying disease, such as for instance a petit mal or grand mal seizure, but that in each case its occurrence needs a special explanation. Based upon the most conspicuous fact, its prevalence in symptomatic and its relatively sporadic occurrence in idiopathic epilepsy, we may first of all conclude that an essential predisposing factor lies in a gross brain damage or in extensive cerebral dysfunction.”
19.	At page 174, there is an important passage dealing with “Precipitating factors”: 
“Hunter (3) and Bamberger and Matthes (1) state that drug withdrawal and infection constitute the most essential causes for the precipitating of status. According to our experience, however, there are still other, apparently different factors, which should be taken into consideration and compared with each other if one wants to find their common denominator. We should first of all keep in mind that very often, even if we do not watch out for it systematically, we hear of some special circumstances immediately preceding the status. It is, therefore, probable that one or more specific causes are responsible for each status; these we intended to detect by a thoroughly planned investigation and questioning.
In a total of 110 case histories no specific circumstances prior to status were recorded in only 37 cases, whereas in 73, that is in almost 2/3 of all cases, particular events immediately preceding the status were registered. As in Hunter’s material infections (23 times) and drug withdrawal (14 times) were the most frequent causes, followed by sleep deprivation (11 times), physical fatigue and concussions (11 times), alcohol (4 times) and fluid ingestion (4 times), cerebral emboly (4 times), over exposure to sun (4 times), procedures for diagnostical purposes such as ventriculography and arteriography (3 times), X-ray treatment of the brain (3 times), excitement (3 times) and high voltage current (once). However the case for case assessment adds two important conclusions to the statistical data: firstly that, as also mentioned by Hunter, usually a combination of several factors must be present in order to form the predisposing condition such as for instance the concurrence of underdose of medication in addition to an infection, or discontinuation of medication, deprivation of sleep and alcohol ingestion, of physical fatigue, overexposure to sun and increased fluid intake.”
20.	Finally, under the heading “Drug withdrawal”: 
“Status after drug withdrawal is the only condition that now remains to be explained. Not all epileptic patients, however, react with status to a withdrawal or an underdose of medication. Only a small proportion of the patients are so affected, and in these cases contributing circumstances play an important role. It is observed only in those patients who have had seizures for many years, - i.e. where a substantial brain damage may be assumed to be present – and then only when additional stress on the brain metabolism occurs, such as general infections, deprivation of sleep, alcohol ingestion or physical fatigue.”
21.	Dr Reynolds said in evidence that this paper supported his trigger theory, since it showed that, where a person was suffering from a withdrawal seizure, status could be triggered by concussion resulting from a relatively minor head injury.  He said that his own experience accorded with the view of Professor Janz that multiple factors sometimes contribute to the precipitating of status and that, if more than one factor is operating, status is more likely to occur.  He was asked about the meaning of the word “immediately” in the context of page 174 (“special circumstances immediately preceding the status”), particularly in the light of the apparent coupling of “physical fatigue and concussions”.  He said: “[Professor Janz] doesn’t say in his paper exactly when the concussion occurred, but I would interpret it to mean that it was a fairly rapid trigger to the status as I have seen myself”.  
22.	The passage in Professor Shorvon’s book relied on by Dr Reynolds is in these terms:
“CEREBRAL TRAUMA: Open-head injuries are more likely than closed head injury to result in status, often in the acute phase (Oxbury & Whitty 1971), as is head injury complicated with intracerebral haemorrhage.  In early seizures due to trauma, 10% present as status epilepticus.”
23.	Dr Reynolds was asked in cross-examination whether the word “early” was being used by Professor Shorvon in contra-distinction to “immediate”.  Dr Reynolds said that this was a distinction which he did not recognise and one which Professor Shorvon did not recognise in his book.  He continued: “When he says 10% may present in status epilepticus after a head injury, he is describing that in the early phase within a week, but this is at any time within the first week after a head injury, whether it be immediate or within the first 24 hours or within the first week”. 
24.	Mr Kent submits that the Janz paper does not support the trigger theory.  First, it is by definition impossible to move “immediately” from an event such as a concussion to the condition of status, because status is defined as recurrent seizures.  Secondly, there is nothing to suggest that any of the cases referred to in the Janz paper involved patients who were already suffering from a seizure at the time of the concussion.  Thirdly, as Professor Chadwick said in his supplementary report, there is no need to look for any further explanation for the status, given the fact that before the head injury the claimant was suffering a seizure.  The “extensive cerebral dysfunction” (referred to by Professor Janz at page 173 as an “essential disposing factor”) was the withdrawal seizure. That is a sufficient explanation for the status in this case.   It is also consistent with the statement by Professor Janz that “drug withdrawal and infection constitute the most essential causes for the precipitating of status”.  
25.	Professor Chadwick said that drug and alcohol withdrawal was a far more common cause of status than head trauma and referred in his supplementary report to a study which showed that between 15% and 25% of status in US communities was attributed to alcohol withdrawal and between 3% and 5% attributed to trauma.  He also said that in his own clinical experience he had never seen a case of status “immediately” following a head injury.  By “immediately” I understand him to mean “straightaway” and not, for example, “ a few hours later”.
26.	In the opinion of Professor Chadwick, there was no support in the literature for the trigger theory.  Even severe head trauma was not associated with immediate, as opposed to early, seizures.  The only example of immediate seizures following a concussion had been shown in an Australian study of rugby footballers (McRory et al BMJ 1997).  These seizures, however, were not epileptic at all, but were simply benign concussive convulsions.  
27.	The judge said at [43] that: 
“…Interesting though that [Australian] paper is, in my judgment, it is the case that there is an absence of any medical learning or literature supporting Professor Chadwick to the extent of saying that status will not be found to occur after a minor head injury, and in Dr Reynolds’ view, Janz and the work by Shorvon, “Status Epilepticus”, indicate the contrary.”
28.	He summarised his finding on the trigger theory at [44] in these terms: 
“Well, says Mr Kent, why is it necessary to look beyond withdrawal of alcohol or benzodiazepine as the cause of the status epilepticus?  For the reasons Dr Reynolds gave, I think it right to do so.  For a quiet witness, he was remarkably confident in his conclusion.  Professor Chadwick acknowledged that trauma as a cause of status was a possibility, although he said the strong balance of probability was against it.  On this issue, and I bear in mind the neuroradiologists’ views as well, I prefer the views of Dr Reynolds and I find his reasons for them compelling.  The distinction between immediate and early onset I do not regard as important, as he did not.  There is good support in the literature for a connection with trauma, even non-severe trauma, and the onset of status.  In my judgment, that explains why on this occasion, the claimant developed a condition which he had never developed on other similar occasions.”
29.	Mr Kent submits that the judge was not entitled to dismiss the views of Professor Chadwick in this way.  The burden of proof was on the claimant.  Professor Chadwick was simply trying to make good a negative point, namely that the only literature that dealt with immediate apparent seizures following head injury was shown to be dealing with something quite different.  Mr Kent submits that the lack of any support in the literature for the trigger theory means that the judge’s conclusion had no support beyond Dr Reynolds’ assertion that he was confident in his conclusion about the theory in this case.  That is not a sufficient way of resolving a difficult technical issue on which two distinguished experts disagreed. 
30.	I accept that, where there is a difference between experts on a fundamental point, it is the task of the court to justify its preference for one over the other by an analysis of the underlying material and of their reasoning.  It is not sufficient, if there is no such material or reasoning, to accept the opinion of one expert rather than another simply on the grounds that he has given his evidence confidently.  There may be cases where the court is unable to decide which opinion is the more persuasive.  Occasionally, where there are alternative explanations for an injury but the court is unable to say on the balance of probabilities which is to be preferred, the claimant will fail on the grounds that he had failed to discharge the burden of proof.  
31.	In this case, the judge did not base his conclusion exclusively or even principally on his preference for the evidence of Dr Reynolds because of the confident way he gave his evidence.  I accept that Dr Reynolds’ own clinical experience (one case) was a slender basis for accepting the trigger theory.  But the judge was entitled to be impressed by the fact that the claimant had had three previous withdrawal seizures none of which resulted in status and that withdrawal seizures in prison are a common occurrence, and yet there was no evidence of a single case where the seizure had resulted in status.  Mr Caussyram and Mr Kedwards gave evidence to this effect.  The evidence of Dr Labinjo was of particular significance.  He worked as a medical officer with the Prison Service from 1994-98 and senior medical officer from 1998-2002.  He said that withdrawal seizures were common in prisons, but he had never encountered a case of status.  
32.	It seems to me, however, that the critical finding of the judge was that there was good support in the medical literature for a connection between trauma and the onset of status.  That support was to be found principally in the paper of Professor Janz, supported to some extent by the book of Professor Shorvon.  
33.	The judge was entitled to conclude that such support was to be found in Professor Janz’s paper.  The paper lists at page 174 the “particular events immediately preceding the status” as including drug withdrawal and physical fatigue and concussion.  It adds importantly that “usually a combination of several factors must be present in order to form the predisposing condition”.  It is clear from the factors which are then mentioned that, although concussion is not included, they are examples of the “particular events immediately preceding the status” to which reference is made earlier in the paragraph which do include concussion.   The need for a “combination” is repeated in the section under the heading “Drug withdrawal”.  The point is made that drug withdrawal leads to status only in patients who have had seizures for many years and then only when additional stress on the brain metabolism occurs “such as general infections, deprivation of sleep, alcohol ingestion or physical fatigue”.  These examples are not exhaustive and do not include concussion, but they overlap with the factors referred to on page 174.  
34.	It seems to me that what Professor Janz is saying is that his study and that of Hunter show that withdrawal seizures on their own do not result in status.  There must be another factor which, taken in conjunction with the withdrawal seizure, will lead to status.  This was how Dr Reynolds interpreted the paper and it accorded with his own experience: see [21] above
35.	Mr Kent also criticises the judge for placing weight on the joint answer given by the neuro-radiologists, Dr McConachie and Dr Kendall, to the question “If the head trauma suffered by the claimant was the trigger to the development of status epilepticus, would this necessarily be detectible radiologically?”  The answer they gave was: “Not necessarily.  We are agreed trauma may induce seizures and even status epilepticus without causing changes detectible on a brain scan.”  Mr Kent says that the answer was conditioned by the hypothesis on which the question was based, namely that the head injury was the trigger for the status.  He also points out that Dr McConachie accepted in his evidence that he did not have the expertise of a neurologist. 
36.	 In my view, the hypothesis built into the question undoubtedly conditioned the first part of the neuro-radiologists’ answer.  But it did not condition the second part of the answer.  In my view, the statement that trauma may induce status was generalised and was independent of the hypothesis that the trauma suffered by the claimant was the trigger to the development of the status.  Nevertheless, in view of the fact that these two doctors are neuro-radiologists and not neurologists, it would have been wrong to place great reliance on this answer.  At [39], the judge said: 
“…[Dr Reynolds’] belief is that the claimant was experiencing what I would call an “ordinary” withdrawal seizure as he fell from bunk to ground, hit his head and the injury that he sustained caused him to go into status.  He said, as the neuro radiologists had agreed, that status can be triggered by head injury, and one which is relatively minor and leaves no radiological sign or trace behind it.  He based this on his own clinical experience;...”
37.	As has been seen, the judge also said at [44] that he bore in mind the views of the neuro-radiologists “as well”.  Nevertheless, it does not seem to me that the judge placed great weight on the joint answer of the neuro-radiologists.  I accept that he would have been wrong to do so.
38.	The challenge to the judge’s finding on causation is a challenge to his findings of fact.  It is not suggested that the judge misdirected himself or misunderstood the evidence. Nor is there a challenge based on lack of reasons.  The challenge is simply based on the submission that the judge erred in preferring the evidence of Dr Reynolds to that of Professor Chadwick.  In my view, such a challenge should only be upheld if this court is satisfied that the judge’s conclusion was clearly wrong.   I am far from being persuaded that the judge was clearly wrong.  On the contrary, for the reasons that I have given, I consider that the judge was entitled to accept Dr Reynolds’ interpretation of the Janz paper and reject the evidence of Professor Chadwick.   
39.	I would, therefore, uphold the judge’s decision on the trigger theory issue.  For the reasons given at [7] above, it follows that I would dismiss the appeal.
Contributory negligence
40.	The cross-appeal raises a point on which, as I have said, there appears to be no direct previous authority.  The question is whether the judge was right to reduce the claimant’s damages by 15% (or at all) because his injuries were caused partly by his addiction which was the result of his lifestyle decisions and, therefore, his “fault” within the meaning of section 1(1) of the Law Reform (Contributory Negligence) Act 1945 (“the 1945 Act”).  The judge said that the law required the claimant to exercise such precautions for his own safety as a man of ordinary prudence would observe: see per Lord Denning MR in Froom v Butcher [1976] QB 286, 294.  The claimant, who was 16 years of age when he embarked on his life of drug and alcohol addiction, must be taken to have foreseen a risk of harm to himself from his habits.  It was sufficient that he must have been aware that taking drugs was something that gave rise to a risk to his health.  He did not have to foresee how the harm might come about: see Jones v Livox Quarries Limited [1954] 2 QB 608, 613-4. 
41.	He said that it had to be shown that the injury sustained was the result of the claimant’s fault.  This issue of causation had to be approached on the robust and pragmatic basis which Lord Bridge approved in Wilsher v Essex Area Health Authority [1988] AC 1074. The judge held that the apportionment, if that stage was reached, between the claimant and the Home Office once contributory negligence was established, was to be approached on the “broad jury like and commonsense way” that Stanley Burnton J adopted in Badger v MOD 3 All ER 173 at [16].  
42.	The judge rejected the submission made on behalf of the claimant that not enough was known about the claimant’s history and life to form the necessary judgments on the issue of contributory negligence.  There was no medical evidence as to the cause of the addiction.  The judge said that he had some information about the claimant and his background.  He came from “a very good family”.  He made a promising start in life.  Sadly, at the age of 15 or 16 he started using drugs, starting with cannabis.  He dropped out of school and other addictions soon followed.  He began to steal to fund his habit and this led to three periods of custody in prison.  In 1991, he had spent some time in the Maudsley Drug Dependency Unit.  In 1994, he spent some time in a rehabilitation centre in Somerset.  He had his first major epileptic seizure in the Maudsley.  He had another one while he was in prison in 1995.  The family were aware of two other seizures that had occurred.  
43.	The judge expressed his conclusion on the issue of contributory negligence in the following way:
“58. Viewed objectively as it must be, in my judgment the claimant has to be described as being at fault in relation to the choices he had made in his life prior to the events of this night.  That fault has caused or contributed to the dreadful injuries in this way, not because they have put him in prison, but because he was knowingly risking injury to his health by doing what he was doing, even if he did not know how it would happen.  This is so as much as if he had wandered abroad in a drug-induced state of intoxication and walked into the path of a negligently driven car.  The analogy is very far from being a perfect one.  It would be simply wrong, reluctant as I am to find this, to say that there was no causative fault of his in operation as part of the events of 3rd November.
59. As to how responsibility should be apportioned on a just and equitable basis as the statute requires me to do, it is my judgment that the prison service failed in its duty to him by some clear margin and the prison service should have been better prepared to deal with epileptic emergencies than it was at least on that occasion.  They must clearly shoulder the majority of responsibility for this event.”
44.	He then said that he would reduce the claimant’s damages when assessed by 15% to reflect his contributory negligence in this case.  
45.	Although the point is not entirely clear, it seems to me that the judge decided that the claimant’s “fault” lay in his choosing a lifestyle of drug and alcohol addiction when he was a teenager.  It did not also lie in his failing subsequently to rid himself of the addiction.   The judge did not have the medical evidence that would have been necessary to enable him to make a finding as to whether the claimant could have abandoned his addiction and was, therefore, at fault in not doing so.
46.	The first ground of the cross-appeal is that there was no evidential basis for the judge’s finding of fault on the part of the claimant in becoming addicted to drugs and alcohol in the first place.  There was no cross-examination of the claimant’s parents on their witness statements and no examination of the medical records to support the allegation of fault on the part of the claimant.  The complex psychological basis of substance abuse was not explored at the trial and no expert evidence was adduced on the question whether the claimant could be said to have been at fault. 
47.	In my view, the judge was entitled to hold that the claimant was at fault in becoming addicted to drugs and alcohol when he was 15 or 16 years of age.  He was entitled to infer that the claimant must have known at that time that the abuse of drugs and alcohol on the scale necessary to lead to addiction was dangerous to his health.  He was also entitled to conclude, without the benefit of medical evidence, that the Home Office had discharged the burden of proving fault.
48.	But Mr Pittaway has a more fundamental submission.  He contends that, even if the claimant was at fault in becoming addicted to drugs and alcohol as a teenager, the damage suffered by him was not partly the result of his fault and/or it is not just and equitable to reduce his damages at all having regard to his share in the responsibility for his injuries.  
49.	Section 1(1) of the 1945 Act provides:
“Where any person suffers damage as the result partly of his own fault and partly of the fault of any other person or persons….the damages recoverable in respect thereof shall be reduced to such extent as the court thinks just and equitable having regard to the claimant’s share in the responsibility for the damage…”
50.	As Lord Walker of Gestingthorpe said in Corr v IBC Vehicles Limited [2008] UKHL 13, [2008] 2 WLR 499 at [44], “in applying this test the court has to have regard both to blameworthiness and to what is sometimes called causal potency: Stapley v Gypsum Mines Limited [1953] AC 663, 682”.
 “The result partly of his own fault”
51.	It is true that, but for his addiction, he would not have suffered a withdrawal seizure on 3 November 1997 and would not, therefore, have fallen from the top bunk and suffered the head injury which triggered the status.  In that sense his injury was the result partly of his addiction.  But in my view the addiction was not a potent cause of the injury.  
52.	It has often been said in the context of contributory negligence that the courts should adopt a broad common sense approach.  In Admiralty Commissioners v SS Volute [1922] 1 AC 129, 144 (a pre-1945 Act case), Lord Birkenhead LC said that “the question of contributory negligence must be dealt with somewhat broadly and upon common-sense principles as a jury would probably deal with it”.   Lord Birkenhead explained (in the context of a collision case) that there are cases where the two acts of negligence “come so closely together, and the second act of negligence is so much mixed up with the state of things brought about by the first act that the party secondly negligent…. might…invoke the prior negligence as being part of the cause of the collision so as to make it a case for contribution.”
53.	Stapley v Gypsum Mines Ltd [1953] AC 663 was a post-1945 Act case.  It involved an accident at the plaintiff’s place of work.  Lord Reid adopted the same approach as Lord Birkenhead and said at page 681:
“One may find that as a matter of history several people have been at fault and that if any one of them had acted properly the accident would not have happened, but that does not mean that the accident must be regarded as having been caused by the faults of all of them.  One must discriminate between those faults which must be regarded as too remote and those which must not. Sometimes it is proper to discard all but one and to regard that one as the sole cause, but in other cases it is proper to regard two or more as having jointly caused the accident.  It may often be dangerous to apply to this kind of case tests which have been used in traffic accidents by land or sea, but in this case I think it useful to adopt phrases from Lord Birkenhead’ speech in Admiralty Commissioners v Volute (Owners), and to ask was Dale’s fault “so much mixed up with the state of things “brought about” by Stapley that “in the ordinary plain common sense of this business” it must be regarded as having contributed to the accident.  I can only say that I think it was and that there was no “sufficient separation of time, place or circumstance” between them to justify its being excluded.”
54.	In a typical accident case, where there are faults on the part of the victim (C) and the defendant (D) both of which then and there directly contribute to the accident, there is no difficulty in finding that C suffers damage partly as a result of his own fault and partly as a result of the fault of D.  Such cases are the regular diet of judges in the courts day in and day out.  Obvious examples are road traffic accident cases where C is injured as a result of the careless driving of both himself and D; and claims by C against his or her employer where the injury is the result of D’s breach of duty in failing to provide a safe system of work but where the accident would have been avoided (or the injury less serious) if C had not acted carelessly.  In such cases, it is obvious that C’s fault is “so much mixed up with the state of things brought about” by D’s fault that it must be regarded as having contributed to the accident and there is no “sufficient separation of time, place or circumstance” between the faults of C and D to justify the exclusion of the C’s fault as a contributory or potent cause.  
55.	In Jones v Livox, the plaintiff was employed by the defendant quarry owner.  In defiance of his employer’s orders, he jumped on to the towbar at the back of a traxcavator, a quarry vehicle.  As the vehicle was moving, a dumper driven by another employee of the defendant crashed into the back of the traxcavator and the plaintiff was injured.  The question was whether the injury was partly the result of the plaintiff’s fault within the meaning of section 1(1) of the 1945 Act.  At page 616, Denning LJ said: 
“There is no clear guidance to be found in the books about causation.  All that can be said is that causes are different from the circumstances in which, or on which, they operate.  The line between the two depends on the facts of each case.  It is a matter of common sense more than anything else…..
In order to illustrate this question of causation, I may say that if the plaintiff, whilst riding on the towbar, had been hit in the eye by a shot from a negligent sportsman, I should have thought that the plaintiff’s negligence would in no way be a cause of his injury.  It would only be the circumstance in which the cause operated.  It would only be part of the history.  But I cannot say that in the present case.  The man’s negligence here was so much mixed up with his injury that it cannot be dismissed as mere history.  His dangerous position on the vehicle was one of the causes of his damage just as it was in Davies v Swan Motor Co (Swansea) Ltd [1949] 2 KB 291.”
56.	In my judgment, the claimant’s fault in becoming addicted to drugs and alcohol in his mid-teens was not a potent cause of the status and the consequent brain injury which were triggered by his fall on 3 November 1997.  It was too remote in time, place and circumstance and was not sufficiently connected with the negligence of the prison staff or, to use Lord Birkenhead’s words, was not sufficiently “mixed up with the state of things brought about” by the prison staff on 3 November to be properly regarded as a cause of the injury.  To use the language of Denning LJ, the claimant’s addiction was no more than part of the history which had led to his being a person whose medical and psychological conditions were as they were when he was admitted to Brixton prison on 29 October 1997.  
57.	The judge recognised that the analogy that he gave at [58] of his judgment of a person wandering abroad in a drug-induced state of intoxication walking into the path of a negligently driven car was very far from being perfect.  I respectfully consider that this is not a good analogy at all.  In my judgment, the fault of such a person (negligently walking into the path of a car) is a potent cause of the injury which he sustains in the accident.  The fault (walking in the road in a drug-induced state of intoxication) is closely connected in time and place with the accident which is caused then and there by a combination of the negligence of the claimant and the defendant.
58.	There is a far closer analogy with the case of a claimant who seeks medical treatment for a condition from which he is suffering as a result of his own fault and sustains injury as a result of negligent treatment.  Examples of such a condition are lung cancer caused by smoking or cirrhosis of the liver caused by excessive consumption of alcohol.  Mr Kent accepts that in such cases it would be wrong to reduce a successful claimant’s damages under the 1945 Act, although it is his fault that he is suffering from the medical condition for which he is being treated and, but for that condition, he would not have required medical treatment in the first place.  One of the reasons why I consider Mr Kent is right to make this concession is that the claimant’s fault in smoking or consuming excessive alcohol over a period of time is not a potent cause of the injury suffered as a result of the negligent medical treatment.  The fault is not sufficiently closely connected with the defendant’s negligence.  Rather, the fault is part of the claimant’s history which has led to his being a man who is suffering from a particular medical condition.  
59.	I would, therefore, hold that the claimant’s injury was not partly the result (within the meaning of section 1(1) of the 1945 Act) of his becoming addicted to drugs and alcohol as a teenager. 
Just and equitable
60.	If, contrary to the above, the claimant’s injury was partly the result of his fault in becoming addicted to drugs and alcohol as a teenager, then I would hold that it is not just and equitable to reduce his damages having regard to his share in the responsibility for the injury.  He informed the prison staff when he arrived at the prison that he was an intravenous heroin user, that he drank heavily and had previously had withdrawal seizures.  The staff (rightly) did not permit him to take drugs or alcohol.  They, therefore, knew or ought to have known that he might suffer from withdrawal seizures and yet they placed him in a top bunk. 
61.	The position of the claimant was analogous to that of a patient who is admitted to a rehabilitation clinic for the express purpose of being weaned off his addiction to drugs.  If such a patient were placed in a top bunk and suffered a withdrawal seizure and injury as a result of a fall to the floor, Mr Kent rightly accepts that his claim for damages would not be reduced for contributory negligence.  He seeks to distinguish such a case on the grounds that the claimant was not admitted to prison for the purpose of being treated for his drug addiction.  That is true, but the prison and the rehabilitation clinic share the common objective of weaning those in their care off drug and alcohol dependency.  The methods by which they seek to achieve this may differ, but their objectives are the same.  It is foreseeable to both the clinic and the prison staff that the person in their care may suffer a withdrawal seizure in the process. 
62.	I do not consider that there is any rational basis for distinguishing between the two cases when determining whether it is just and equitable to reduce the damages having regard to the claimant’s share in the responsibility for the injury.  I do not see how the respective blameworthiness of the parties can be affected by whether the claimant was admitted to a clinic for the express purpose of being cured of his drug and alcohol dependency (with the attendant risk of withdrawal seizures) or admitted to a prison where he will not be allowed to satisfy his addiction (with the same or similar attendant risk of withdrawal seizures).  In both cases, the claimant presents himself to an authority as a person suffering from an addiction; in both cases, the authority assumes a responsibility for the claimant’s welfare, knowing that the claimant suffers from the addiction and what may happen if the drugs and/or alcohol are withdrawn.   The artificiality of the distinction drawn by Mr Kent is illustrated by the fact that the prison authorities might decide that an inmate suffering from drug or alcohol dependency needs to be admitted to the prison hospital for treatment following the withdrawal of the drugs and alcohol.  It makes little sense to say that the damages should not be reduced for contributory negligence if the negligence occurs while the claimant is being weaned off the drugs and alcohol in the prison hospital, but that the damages should be reduced if the negligence occurs while the claimant is being weaned off the drugs and alcohol while being accommodated in the main prison.
63.	In my judgment, even if (contrary to the view I have expressed above) there were causative potency in the claimant’s fault in this case, for the reasons explained at [51] to [59] above, it is minimal.  That fact, taken in conjunction with the comparative blameworthiness of the parties leads me to conclude that the judge was wrong to hold that it was just and equitable to reduce the damages payable to the claimant.   
Overall conclusion
64.	I would, therefore, dismiss the appeal and allow the cross-appeal and hold that there should be no reduction for contributory negligence from the damages when they are assessed.  
Lord Justice Lloyd:
65.	I agree that the appeal should be dismissed and the cross-appeal allowed, for the reasons given by Dyson LJ.
Lord Justice Ward:
66.	I also agree.