Parliamentary
Archives,
HL/PO/JU/18/248
Hilsher (Respondent)
v.
Essex
Area Health Authority (Appellants)
JUDGMENT
Die Jovis 10° Martii 1988
Upon Report from the Appellate Committee to
whom was
referred the Cause Wilsher against Essex Area
Health
Authority, That the Committee had heard Counsel on Monday
the
1st, Tuesday the 2nd, Wednesday the 3rd, Thursday the
4th,
Monday the 8th and Tuesday the 9th days of February last,
upon
the Petition and Appeal of Essex Area Health Authority,
of
Hamstel Road, Harlow, Essex, CM20 1RB, praying that the
matter
of the Order set forth in the Schedule thereto, namely
an
Order of Her Majesty's Court of Appeal of the 24th day of
July
1986, might be reviewed before Her Majesty the Queen in
Her
Court of Parliament and that the said Order might be
reversed,
varied or altered or that the Petitioners might have
such
other relief in the premises as to Her Majesty the Queen
in
Her Court of Parliament might seem meet; as upon the Case
of
Martin Graham Wilsher (an infant) lodged by Heather
Marjorie
Wilsher, his mother and Next Friend, in answer to the
said
Appeal; and due consideration had this day of what was
offered
on either side in this Cause:
It is Ordered and Adjudged, by
the Lords Spiritual and
Temporal in the Court of Parliament of Her
Majesty the Queen
assembled, That the said Order of Her Majesty's
Court of
Appeal (Civil Division) of the 24th day of July 1986 and
the
Order of Mr. Justice Peter Pain of the 21st day of
December
1984 complained of in the said Appeal be, and the same
are
hereby, Set Aside, save as to costs, and that the Cause
be,
and the same is hereby, remitted back to the Queen's
Bench
Division of the High Court of Justice with a Direction
that
there be a retrial before a different judge of the
issue
whether the negligence of the Appellants, as found by
the
Court of Appeal, caused or materially contributed to
the
Respondent's retrolental fibroplasia: That the money paid
into
Court pursuant to the Order of the Court of Appeal should
remain
in Court pending the retrial: And it is further
Ordered,
That the costs incurred by the Respondent in respect
of the said
Appeal to this House be taxed in accordance with
Schedule 2 to the
Legal Aid Act 1974.
Cler: Parliamentor:
Judgment: 10.3.88
HOUSE OF LORDS
WILSHER
(RESPONDENT)
v.
ESSEX AREA HEALTH
AUTHORITY
(APPELLANTS)
Lord Bridge of Harwich
Lord
Fraser of Tullybelton
Lord
Lowry
Lord
Griffiths
Lord
Ackner
LORD BRIDGE OF HARWICH
My Lords,
The infant plaintiff was born
nearly three months
prematurely on 15 December 1978. He weighed
only 1200
grammes. In the first few weeks of life he suffered from
most of
the afflictions which beset premature babies. He passed
through a
series of crises and very nearly died. The greatest
danger which
faces the very premature baby, on account of the
imperfect
function of incompletely developed lungs, is death or
brain damage
from failure of the oxygen supply to the brain. That
Martin not
only survived but also now retains unimpaired brain
function is due
both to the remarkable advances of medical science
and technology
in this field in comparatively recent years and to
the treatment he
received in the special baby care unit of the
Princess Alexandra
Hospital, Harlow.
Tragically, however, he succumbed
to another well-known
hazard of prematurity. He suffers from
retrolental fibroplasia
(RLF), an incurable condition of the
retina which, in his case, has
caused total blindness in one eye
and severely impaired vision in
the other. He sued the Essex Area
Health Authority ("the
authority") who are responsible
for the Princess Alexandra Hospital,
Harlow, on the ground that
his RLF was caused by an excess of
oxygen tension in his
bloodstream in the early weeks attributable
to a want of proper
skill and care in the management of his
oxygen supply. The action
was heard by Peter Pain J. and the
trial lasted 20 days. In
addition to the evidence of the medical
and nursing staff at the
hospital, the judge heard expert evidence
from two paediatricians
and two ophthalmologists called for the
plaintiff and from three
paediatricians and one ophthalmologist
called for the authority.
All were highly qualified and
distinguished experts in their
respective fields. In addition, no less
than 24 articles from
medical journals about RLF covering 129
foolscap pages of print
were put in evidence.
The allegations of negligence
against the authority related
to two quite distinct phases of
Martin's treatment. The first
concerned the first 38 hours after
his birth. In order to monitor
the partial pressure of oxygen
(PO2) in the arterial blood of a
premature baby, it is
standard practice to pass a catheter through
the umbilical artery
into the aorta. This enables the PO2 to be
measured in
two ways. At the tip of the catheter is an electronic
sensor
connected to a monitor outside the body which, if
correctly
calibrated, should give an accurate reading of the PO2.
In
addition, an aperture in the catheter close to the sensor
enables
samples of blood to be taken for conventional blood
analysis at
regular intervals to check and, if necessary, adjust
the monitor's
calibration. Again it is standard practice to check
the location of
the sensor by X-ray after the catheter has been
inserted. In
Martin's case the catheter was inserted by mistake
into a vein
instead of an artery so that the sensor and the
sampling aperture
were wrongly located in the heart instead of the
aorta. This
meant that they would sample a mixture of arterial and
venous
blood instead of pure arterial blood, which would
consequently give
a false reading of the level of PO2
in the arterial blood. The
house officer and the registrar who
were on duty at the material
time and who saw the X-ray which was
taken both failed to notice
the mistake. The judge held this
failure to amount to negligence
for which the authority were
liable. The plaintiff's case in
relation to this first allegation
of negligence was that the
misplaced catheter gave readings of PO2
well below the true level
of PO2 in the arterial blood
which led to excessive administration
of oxygen in an attempt to
raise the PO2 level and that in
consequence the true
PO2 level was excessively high for a
substantial period
until the mislocation of the catheter was
realised at 8 o'clock on
the morning of 17 December 1978.
A second phase of Martin's
treatment alleged to have been
negligent was between 20 December
1978 and 23 January 1979.
Between these dates it was alleged that
there were five distinct
periods of differing duration when the
medical and nursing staff
responsible for Martin's care were in
breach of duty in allowing
the level of PO2 in his
arterial blood to remain above the
accepted level of safety. The
judge found that four of these five
periods of exposure to an
unduly high level of PO2 were due to
the authority's
negligence.
In making his finding of
negligence in relation to each of
the periods of raised PO2
levels except the first attributable to
the misplaced catheter,
the judge relied upon a principle of law
which he thought was laid
down by this House in McGhee v.
National Coal Board [1973] 1 WLR 1 and which he had stated in
his own earlier decision in
Clark v. MacLennan [1983] 1 A11.E.R.
416, 427 in the
following terms:
"It seems to me that it
follows from McGhee that where
there is a situation in
which a general duty of care arises
and there is a failure to take
a precaution, and that very
damage occurs against which the
precaution is designed to
be a protection, then the burden lies on
the defendant to
-2 -
show that he was not in breach of
duty as well as to show
that the damage did not result from his
breach of duty."
The judge thought that this
proposition of law derived support
from the decision at first
instance of Mustill J. in Thompson v.
Smiths Shiprepairers
(North Shields) Ltd. [1984] Q.B. 405. He held
that the authority
had failed to prove on a balance of probabilities
either that they
were not negligent or that their negligence did
not cause or
materially contribute to Martin's RLF. He therefore
held them
liable in damages and gave judgment for the plaintiff
for
£116,199.14.
The Court of Appeal (Sir Nicolas
Browne-Wilkinson, V.-C.,
Mustill and Glidewell L.JJ) affirmed this
judgment by a majority,
the Vice-Chancellor dissenting [1987] 1
Q.B. 730. They gave leave
on terms to the authority to
appeal to this House. A number of
issues were argued in the Court
of Appeal. They unanimously
affirmed the finding of negligence
against the authority, though by
marginally different processes of
reasoning, on the ground of the
authority's vicarious liability
for the registrar's failure to observe
from the X-ray that the
first catheter inserted into Martin's
umbilicus was located in a
vein not in an artery. They
unanimously reversed the judges'
finding of negligence in relation
to the later periods when the
level of PO2 in Martin's blood was
raised on the ground
that he had misdirected himself in holding
that the burden of
proof was reversed so that it lay upon the
authority to show that
they were not negligent. On examination
of the evidence the Court
of Appeal found that no negligence was
established in relation to
these later periods. No issue arises in
the present appeal to your
Lordships' House in respect of either of
these conclusions on
liability and nothing more need be said about
them. The crucial
issue which now arises and on which the Court
of Appeal were
divided in their opinions is whether the judgment
can be affirmed
on the ground that any raised level of PO2 in
Martin's
arterial blood before 8 o'clock on the morning or 17
December 1978
consequent on misplacement of the catheter caused
or materially
contributed to Martin's RLF.
My Lords, I understand that all
your Lordships agree that
this appeal has to be allowed and that
the inevitable consequence
of this is that the outstanding issue
of causation must, unless the
parties can reach agreement, be
retried by another judge. In
these circumstances, for obvious
reasons, it is undesirable that I
should go into the highly
complex and technical evidence on which
the issue depends any
further than is strictly necessary to explain
why, in common with
all your Lordships, I feel ineluctably driven
to the unpalatable
conclusion that it is not open to the House to
resolve the issue
one way or the other, so that a question
depending on the
consequence of an event occurring in the first
two days of
Martin's life will now have to be investigated all over
again when
Martin is nearly ten years old. On the other hand, the
appeal
raises a question of law as to the proper approach to issues
of
causation which is of great importance and of particular
concern
in medical negligence cases. This must be fully
considered.
There was in the voluminous expert
evidence given at the
trial an irreconcilable conflict of opinion
as to the cause of
Martin's RLF. It was common ground that a
sufficiently high
- 3 -
level of PO2 in the
arterial blood of a very premature baby, if
maintained for a
sufficiently long period of time, can have a toxic
effect on the
immature blood vessels in the retina leading to a
condition which
may either regress or develop into RLF. It was
equally common
ground, however, that RLF may occur in
premature babies who have
survived without any artificial
administration of oxygen and that
there is evidence to indicate a
correlation between RLF and a
number of other conditions from
which premature babies commonly
suffer (e.g. apnoeia, hypercarbia,
intraventricular haemorrhage,
patent ductus arteriosus, all
conditions which afflicted Martin)
although no causal mechanisms
linking these conditions with the
development of RLF have been
positively identified. However, what,
if any, part artificial
administration of oxygen causing an unduly
high level of PO2 in
Martin's arterial blood played in
the causation of Martin's RLF
was radically in dispute between the
experts. There was certainly
evidence led in support of the
plaintiff's case that high levels of
PO2 in general
and, more particularly, the level of PO2 maintained
when
the misplaced catheter was giving misleadingly low readings
of the
level in the arterial blood were probably at least a
contributory
cause of Martin's RLF. If the judge had directed
himself that it
was for the plaintiff to discharge the onus of
proving causation
on a balance of probabilities and had indicated
his acceptance of
this evidence in preference to the contrary
evidence led for the
authority, a finding in favour of the plaintiff
would have been
unassailable. That is why it is conceded by Mr.
Henry Brooke Q.C.,
for the authority, that the most he can ask
for, if his appeal
succeeds, is an order for retrial of the causation
issue. However,
the burden of the relevant expert evidence led
for the authority,
to summarise it in very general terms, was to
the effect that any
excessive administration of oxygen which
resulted from the
misplacement of the catheter did not result in
the PO2
in the arterial blood being raised to a sufficiently high
level
for a sufficient length of time to have been capable of
playing
any part in the causation of Martin's RLF. One of the
difficulties
is that, underlying this conflict of medical opinion,
there was
not only a profound difference of view about the
aetiology and
causation of RLF in general but also a substantial
difference as
to the inferences which were to be drawn from the
primary facts,
as ascertained from the clinical notes about
Martin's condition
and treatment at the material time and
amplified by the oral
evidence of Dr. Wiles, the senior house
officer in charge, as to
what the actual levels of PO2 in Martin's
arterial
blood were likely to have been during a critical period
between 10
p.m. on 16 December when Martin was first being
administered pure
oxygen through a ventilator and 8 a.m. the next
morning when,
after discovery of the mistake about the catheter,
the level of
oxygen administration was immediately reduced.
Having found the authority
negligent in relation to the five
periods when the PO2
level was unduly high, the judge added:
"There is no dispute that
this materially increased the risk
of RLF."
This statement, it is now
accepted, was a misunderstanding
of the evidence. Whilst it was
common ground that one of the
objects of monitoring and
controlling the PO2 level in the arterial
blood of a
premature baby in 1978 was to avoid or reduce the risk
- 4 -
of RLF, it was certainly not
accepted by the defence that any of
the levels to which Martin was
subjected were sufficient in degree
or duration to have involved
any material increase in that risk.
This misunderstanding was one
of the factors which led the judge
to the conclusion that Martin
had established a prima facie case
on the issues of causation. He
then said:
"But it is open to the
defendants on the facts of this case
to show that they are not
liable for this negligence because
on the balance of probability
this exposure did not cause
Martin's RLF."
It was on this premise that the
judge examined the issue of
causation. In a judgment which runs to
68 pages of transcript,
only two and a half pages are devoted to
this issue. The judge
repeatedly emphasised that the onus was on
the authority, saying
at one point:
"For the purpose of this
action I need go no further than to
consider whether the breaches
have probably made no
substantial contribution to the plaintiff's
condition."
And, again, a little later on:
"So I have to consider
whether the exposure that occurred
probably did no harm."
After a brief reference to the
evidence of one of the
plaintiff's witnesses and one of the
authority's witnesses whose
answers were based on an assumption of
fact which he was invited
to make, the judge expressed his
conclusion in the following
passage:
"On the basis of this
evidence I find that the defendants
fail to show that the first
and third periods of exposure did
not do any damage; indeed the
probability is that they did.
As to the second, fourth and
fifth periods the position is
more doubtful. The trouble is the
lack of data. The blood
gas readings were not sufficiently
frequent to enable us to
assess whether the excessively high
readings were a peak or
whether they indicate a longer period;
indeed, it is possible
that the true figure went higher. The
defendants, in my
view, have failed to show that these periods did
not cause
or materially contribute to Martin's RLF." (My
emphasis)
Mr. David Latham Q.C., seeking to
uphold the judgment in
Martin's favour, naturally relied heavily
on the words I have
emphasised in this passage and pointed to the
contrast between the
judge's view, thereby expressed, of the
causative effect of what is
now the only relevant period of
exposure calling for consideration
and his doubts about the effect
of three of the four later periods.
He urged your Lordships to
read this as an indication by the judge
that, if he had held the
onus to lie on the plaintiff, he would have
found it discharged on
a balance of probabilities. The Court of
Appeal did not feel able
to accede to a similar submission and I
agree with them. As
Mustill L.J. pointed out [1987] 1 Q.B. 730,
763G, the judge
expressed no preference for the plaintiff's experts
on this point.
Moreover, it is inconceivable that this very careful
judge, if he
had directed himself that the burden of proof lay on
- 5 -
the plaintiff, would not have
subjected the complex and conflicting
evidence to a thorough
scrutiny and analysis before committing
himself to an orthodox
finding of causation in the plaintiff's
favour.
Both parties accepted that the
conflict of evidence was of
such a nature that it could not
properly be resolved by your
Lordships simply reading the
transcript. Indeed, we were not
asked to examine the totality of
the voluminous medical evidence.
Just as Mr. Brooke accepted that
it was not open to the House to
dismiss the plaintiff's claim, so
Mr. Latham accepted that, if he
failed in the submission which I
have examined and rejected in the
foregoing paragraph, he could
not invite the House to make an
independent finding in the
plaintiff's favour on the simple basis
that the expert evidence on
a balance of probabilities affirmatively
established causation.
The Court of Appeal, although they
felt unable to resolve
the primary conflict in the expert evidence
as to the causation of
Martin's RLF, did make a finding that the
levels of PO2 which
Martin experienced in consequence
of the misplacement of the
catheter were of a kind capable of
causing RLF. Mustill L.J. at
p. 766D expressed his anxiety as to
whether "by making a further
finding on an issue where there
was a sharp conflict between the
expert witnesses, we are not
going too far in the effort to avoid a
retrial." But he
concluded at p. 766E that it was "legitimate,
after reading
and re-reading the evidence," to make this finding
based on
"the weight of the expert evidence." This finding by
the
Court of Appeal is challenged by Mr. Brooke, for the
authority, as
one which it was not open to them to make. I must
return to
this issue later. But assuming, as I do for the present,
that the
finding was properly made, it carried the plaintiff's
case no
further than to establish that oxygen administered to
Martin as a
consequence of the negligent failure to detect the
misplacement of
the catheter was one of a number of possible
causes of Martin's
RLF.
Mustill L.3. subjected the
speeches in McGhee v. National
Coal Board [1973] 1 WLR 1
to a careful scrutiny and analysis
and concluded that they
established a principle of law which he
expressed in the following
terms at pp. 771-772:
"If it is an established fact
that conduct of a particular
kind creates a risk that injury will
be caused to another or
increases an existing risk that injury
will ensue; and if the
two parties stand in such a relationship
that the one party
owes a duty not to conduct himself in that way;
and if the
first party does conduct himself in that way; and if
the
other party does suffer injury of the kind to which the
risk
related; then the first party is taken to have caused
the
injury by his breach of duty, even though the existence
and
extent of the contribution made by the breach cannot
be
ascertained."
Applying this principle to the
finding that the authority's
negligence was one of the possible
causes of Martin's RLF, he held
that this was sufficient to enable
the court to conclude that the
negligence was "taken to have
caused the injury." Glidewell L.J.
reached the same
conclusion by substantially the same process of
reasoning. The
Vice-Chancellor took the opposite view.
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The starting point for any
consideration of the relevant law
of causation is the decision of
this House in Bonnington Castings
Ltd, v. Wardlaw [1956] AC 613. This was the case of a pursuer
who, in the course of his
employment by the defenders, contracted
pneumoconiosis over a
period of years by the inhalation of invisible
particles of silica
dust from two sources. One of these (pneumatic
hammers) was an
"innocent" source, in the sense that the pursuer
could
not complain that his exposure to it involved any breach of
duty
on the part of his employers. The other source, however,
(swing
grinders) arose from a breach of statutory duty by the
employer.
Delivering the leading speech in the House Lord Reid
said at pp.
619-620:
"The Lord Ordinary and the
majority of the First Division
have dealt with this case on the
footing that there was an
onus on the defenders, the appellants,
to prove that the dust
from the swing grinders did not cause the
pursuer's disease.
This view was based on a passage in the
judgment of the
Court of Appeal in Vyner v. Waldenberg Brothers
Ltd. [1946]
K.B. 50: 'If there is a definite breach of a
safety provision
imposed on the occupier of a factory, and a
workman is
injured in a way which could result from the breach,
the
onus of proof shifts on to the employer to show that
the
breach was not the cause. We think that that principle lies
at
the very basis of statutory rules of absolute duty' (per
Scott
L.J. at p. 55). ... Of course, the onus was on the
defendants to
prove delegation (if that was an answer) and
to prove contributory
negligence, and it may be that that is
what the Court of Appeal
had in mind. But the passage
which I have cited appears to go
beyond that, and, in so far
as it does so, I am of opinion that it
is erroneous.
It would seem obvious in principle
that a pursuer or plaintiff
must prove not only negligence or
breach of duty but also
that such fault caused or materially
contributed to his
injury, and there is ample authority for that
proposition both
in Scotland and in England. I can find neither
reason nor
authority for the rule being different where there is
breach
of a statutory duty. The fact that Parliament imposes
a
duty for the protection of employees has been held to
entitle
an employee to sue if he is injured as a result of a
breach of
that duty, but it would be going a great deal
farther to hold that
it can be inferred from the enactment
of a duty that Parliament
intended that any employee
suffering injury can sue his employer
merely because there
was a breach of duty and it is shown to be
possible that his
injury may have been caused by it. In my
judgment, the
employee must in all cases prove his case by the
ordinary
standard of proof in civil actions; he must make it
appear
at least that on a balance of probabilities the breach
of
duty caused or materially contributed to his injury."
Lord Tucker said of Scott
L.J.'s dictum in Vyner v. Waldenberg
Brothers Ltd.,
at pp. 624-625:
'I think it is desirable that your
Lordships should take this
opportunity to state in plain terms
that no such onus exists
unless the statute or statutory
regulation expressly or
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impliedly so provides, as in
several instances it does. No
distinction can be drawn between
actions for common law
negligence and actions for breach of
statutory duty in this
respect. In both the plaintiff or pursuer
must prove (a)
breach of duty and (b) that such breach caused the
injury
complained of - (See Wakelin v. London and South
Western
Railway Co. (1886) 12 App. Cas. 41 and Caswell v.
Powell
Duffryn Associated Collieries [1940] A.C. 152). In
each case
it will depend upon the particular facts proved and
the
proper inferences to be drawn therefrom whether the
pursuer
has sufficiently discharged the onus that lies upon
him."
Lord Keith of Avonholm said at p. 625:
"The onus is on the pursuer
to prove his case, and I see no
reason to depart from this
elementary principle by invoking
certain rules of onus said to be
based on a correspondence
between the injury suffered and the evil
guarded against by
some statutory regulation. I think most, if not
all, of the
cases which professed to lay down or to recognise
some
such rule could have been decided as they were on
simple
rules of evidence, and I agree that the case of Vyner
[1946]
K.B. 50, in so far as it professed to enunciate a principle
of
law inverting the onus of proof cannot be supported."
Viscount Simonds and Lord Somervell of Harrow agreed.
Their Lordships concluded,
however, from the evidence that
the inhalation of dust to which
the pursuer was exposed by the
defenders' breach of statutory duty
had made a material
contribution to his pneumoconiosis which was
sufficient to
discharge the onus on the pursuer of proving that
his damage was
caused by the defenders' tort.
A year later the decision in
Nicholson v. Atlas Steel
Foundry and Engineering Co. Ltd.
[1957] 1 W.L.R. 613 followed the
decision in Bonnington
Castings Ltd, v. Wardlaw and held, in
another case of
pneumoconiosis, that the employers were liable for
the employee's
disease arising from the inhalation of dust from
two sources, one
"innocent" the other "guilty," on facts
virtually
indistinguishable from those in the case of Bonnington
Castings
Ltd. v. Wardlaw.
In McGhee v. National Coal
Board [1973] 1 WLR 1 the
pursuer worked in a brick kiln in
hot and dusty conditions in which
brick dust adhered to his sweaty
skin. No breach of duty by his
employers, the defenders, was
established in respect of his working
conditions. However, the
employers were held to be at fault in
failing to provide adequate
washing facilities which resulted in the
pursuer having to bicycle
home after work with his body still
caked in brick dust. The
pursuer contracted dermatitis and the
evidence that this was
caused by the brick dust was accepted.
Brick dust adhering to the
skin was a recognised cause of
industrial dermatitis and the
provision of showers to remove it
after work was a usual
precaution to minimise the risk of the
disease. The precise
mechanism of causation of the disease,
however, was not known and
the furthest the doctors called for
the pursuer were able to go
was to say that the provision of
- 8 -
showers would have materially
reduced the risk of dermatitis.
They were unable to say that it
would probably have prevented the
disease.
The pursuer failed before the Lord
Ordinary and the First
Division of the Court of Session on the
ground that he had not
discharged the burden of proof of
causation. He succeeded on
appeal to the House of Lords. Much of
the academic discussion to
which this decision has given rise has
focussed on the speech of
Lord Wilberforce, particularly on two
paragraphs. He said at p. 6:
"But the question remains
whether a pursuer must
necessarily fail if, after he has shown a
breach of duty,
involving an increase of risk of disease, he
cannot positively
prove that this increase of risk caused or
materially
contributed to the disease while his employers
cannot
positively prove the contrary. In this intermediate
case
there is an appearance of logic in the view that the
pursuer,
on whom the onus lies, should fail - a logic which
dictated the
judgments below. The question is whether we
should be satisfied in
factual situations like the present,
with this logical approach.
In my opinion, there are further
considerations of importance.
First, it is a sound principle
that where a person has, by breach
of a duty of care,
created a risk, and injury occurs within the
area of that
risk, the loss should be borne by him unless he
shows that it
had some other cause. Secondly, from the
evidential point
of view, one may ask, why should a man who is
able to
show that his employer should have taken
certain
precautions, because without them there is a risk, or
an
added risk, of injury or disease, and who in fact
sustains
exactly that injury or disease, have to assume the burden
of
proving more; namely, that it was the addition to the
risk,
caused by the breach of duty, which caused or
materially
contributed to the injury? In many cases, of which
the
present is typical, this is impossible to prove, just
because
honest medical opinion cannot segregate the causes of
an
illness between compound causes. And if one asks which of
the
parties, the workman or the employers should suffer
from this
inherent evidential difficulty, the answer as a
matter in policy
or justice should be that it is the creator
of the risk who, ex
hypothesi must be taken to have
foreseen the possibility of
damage, who should bear its
consequences."
He then referred to the cases of
Bonnington Castings Ltd, v.
Wardlaw [1956] AC 613 and
Nicholson v. Atlas Steel Foundry and
Engineering Co. Ltd.
[1957] 1 W.L.R. 613 and added at p. 7:
"The present factual
situation has its differences: the
default here consisted not in
adding a material quantity to
the accumulation of injurious
particles but by failure to take
a step which materially increased
the risk that the dust
already present would cause injury. And I
must say that, at
least in the present case, to bridge the
evidential gap by
inference seems to me something of a fiction,
since it was
precisely this inference which the medical expert
declined to
make. But I find in the cases quoted an analogy
which
suggests the conclusion that, in the absence of proof
that
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the culpable addition had, in
the result, no effect, the
employers should be liable for an
injury, squarely within the
risk which they created and that they,
not the pursuer,
should suffer the consequence of the
impossibility,
foreseeably inherent in the nature of his injury,
of
segregating the precise consequence of their default."
(I
have added the emphasis in both these two passages.)
My Lords, it seems to me that both
these paragraphs,
particularly in the words I have emphasised,
amount to saying that,
in the circumstances, the burden of proof
of causation is reversed
and thereby to run counter to the
unanimous and emphatic opinions
expressed in Bonnington
Castings Ltd, v. Wardlaw [1956] AC 613
to the contrary
effect. I find no support in any of the other
speeches for the
view that the burden of proof is reversed and, in
this respect, I
think Lord Wilberforce's reasoning must be regarded
as expressing
a minority opinion.
A distinction is, of course,
apparent between the facts of
Bonnington Castings Ltd, v.
Wardlaw, where the "innocent" and
"guilty"
silica dust particles which together caused the pursuer's
lung
disease were inhaled concurrently and the facts of McGhee
v.
National Coal Board [1973] 1 WLR 1 where the "innocent"
and
"guilty" brick dust was present on the pursuer's
body for
consecutive periods. In the one case the concurrent
inhalation of
"innocent" and "guilty" dust
must both have contributed to the
cause of the disease. In the
other case the consecutive periods
when "innocent" and
"guilty" brick dust was present on the
pursuer's body
may both have contributed to the cause of the
disease or,
theoretically at least, one or other may have been the
sole cause.
But where the layman is told by the doctors that the
longer the
brick dust remains on the body, the greater the risk of
dermatitis,
although the doctors cannot identify the process of
causation
scientifically, there seems to be nothing irrational in
drawing
the inference, as a matter of common sense, that the
consecutive
periods when brick dust remained on the body probably
contributed
cumulatively to the causation of the dermatitis. I
believe that a
process of inferential reasoning on these general
lines underlies
the decision of the majority in McGhee's case.
In support of this view, I refer
to the following passages.
Lord Reid said at pp. 3-4:
"The medical witnesses are in
substantial agreement.
Dermatitis can be caused, and this
dermatitis was caused,
by repeated minute abrasion of the outer
horny layer of the
skin followed by some injury to or change in
the underlying
cells, the precise nature of which has not yet
been
discovered by medical science. If a man sweats profusely
for
a considerable time the outer layer of his skin is
softened and
easily injured. If he is then working in a
cloud of abrasive brick
dust, as this man was, the particles
of dust will adhere to his
skin in considerable quantity and
exertion will cause them to
injure the horny layer and
expose to injury or infection the
tender cells below. Then
in some way not yet understood dermatitis
may result.
If the skin is not thoroughly
washed as soon as the man
ceases work that process can continue at
least for some
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considerable time. This man had to
continue exerting
himself after work by bicycling home while still
caked with
sweat and grime, so he would be liable to further
injury
until he could wash himself thoroughly. Washing is the
only
practicable method of removing the danger of further injury.
The effect of such abrasion of the
skin is cumulative in the
sense that the longer a subject is
exposed to injury the
greater the chance of his developing
dermatitis: it is for
that reason that immediate washing is well
recognised as a
proper precaution."
He concluded at pp. 4-5:
"The medical evidence is to
the effect that the fact that
the man had to cycle home caked with
grime and sweat
added materially to the risk that this disease
might develop.
It does not and could not explain just why that is
so. But
experience shows that it is so. Plainly that must
be
because what happens while the man remains unwashed can
have
a causative effect, though just how the cause operates
is
uncertain. I cannot accept the view expressed in the
Inner House
that once the man left the brick kiln he left
behind the causes
which made him liable to develop
dermatitis. That seems to me
quite inconsistent with a
proper interpretation of the medical
evidence. Nor can I
accept the distinction drawn by the Lord
Ordinary between
materially increasing the risk that the disease
will occur and
making a material contribution to its occurrence.
There may be some logical ground
for such a distinction
where our knowledge of all the material
factors is complete.
But it has often been said that the legal
concept of
causation is not based on logic or philosophy. It is
based on
the practical way in which the ordinary man's mind works
in
the everyday affairs of life. From a broad and
practical
viewpoint I can see no substantial difference between
saying
that what the defender did materially increased the risk
of
injury to the pursuer and saying that what the defender
did
made a material contribution to his injury."
Lord Simon of Glaisdale said at p. 8:
"But Bonnington Castings
Ltd, v. Wardlaw [1956] AC 613
and Nicholson v. Atlas
Steel Foundry Engineering Co. Ltd.
[1957] 1 W.L.R. 613
establish, in my view, that where an
injury is caused by two (or
more) factors operating
cumulatively, one (or more) of which
factors is a breach of
duty and one (or more) is not so, in such a
way that it is
impossible to ascertain the proportion in which the
factors
were effective in producing the injury or which factor
was
decisive, the law does not require a pursuer or plaintiff
to
prove the impossible, but holds that he is entitled to
damages
for the injury if he proves on a balance of
probabilities that the
breach or breaches of duty contributed
substantially to causing
the injury. If such factors so
operate cumulatively, it is, in my
judgment, immaterial
whether they do so concurrently or
successively."
Lord Kilbrandon said at p. 10:
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"In the present case, the
pursuer's body was vulnerable,
while he was bicycling home, to the
dirt which had been
deposited on it during his working hours. It
would not have
been if he had had a shower. If showers had been
provided
he would have used them. It is admittedly more
probable
that disease will be contracted if a shower is not taken.
In
these circumstances I cannot accept the argument
that
nevertheless it is not more probable than not that, if
the
duty to provide a shower had not been neglected, he would
not
have contracted the disease. The pursuer has after all,
only to
satisfy the court of a probability, not to
demonstrate an
irrefragable chain of causation, which in a
case of dermatitis, in
the present state of medical
knowledge, he could probably never
do."
Lord Salmon said at pp. 11-12:
"I, of course, accept that
the burden rests upon the pursuer
to prove, on a balance of
probabilities, a causal connection
between his injury and the
defenders' negligence. It is not
necessary, however, to prove that
the defenders' negligence
was the only cause of injury. A factor,
by itself, may not
be sufficient to cause injury but if, with
other factors, it
materially contributes to causing injury, it is
clearly a cause
of injury. Everything in the present case depends
upon what
constitutes a cause. I venture to repeat what I said
in
Alphacell Ltd, v. Woodward [1972] AC 824, 847:
'The
nature of causation has been discussed by many
eminent
philosophers and also by a number of learned judges in
the
past. I consider, however, that what or who has caused
a
certain event to occur is essentially a practical question
of
fact which can best be answered by ordinary commonsense
rather
than abstract metaphysical theory.' In the
circumstances of the present case
it seems to me unrealistic
and contrary to ordinary commonsense to
hold that the
negligence which materially increased the risk of
injury did
not materially contribute to causing the injury."
Then after referring to the
cases of Bonnington Castings Ltd, v.
Wardlaw and
Nicholson he added at pp. 12-13:
"I do not find the attempts
to distinguish those authorities
from the present case at all
convincing. In the
circumstances of the present case, the
possibility of a
distinction existing between (a) having
materially increased
the risk of contracting the disease, and (b)
having materially
contributed to causing the disease may no doubt
be a
fruitful source of interesting academic discussions
between
students of philosophy. Such a distinction is, however,
far
too unreal to be recognised by the common law."
The conclusion I draw from these
passages is that McGhee
v. National Coal Board [1973] 1 WLR 1 laid down no new
principle of law whatever. On the
contrary, it affirmed the
principle that the onus of proving
causation lies on the pursuer or
plaintiff. Adopting a robust and
pragmatic approach to the
undisputed primary facts of the case,
the majority concluded that
it was a legitimate inference of fact
that the defenders'
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negligence had materially
contributed to the pursuer's injury. The
decision, in my opinion,
is of no greater significance than that and
the attempt to extract
from it some esoteric principle which in
some way modifies, as a
matter of law, the nature of the burden
of proof of causation
which a plaintiff or pursuer must discharge
once he has
established a relevant breach of duty is a fruitless
one.
In the Court of Appeal in the
instant case Sir Nicolas
Browne-Wilkinson V.-C., being in a
minority, expressed his view on
causation with understandable
caution. But I am quite unable to
find any fault with the
following passage in his dissenting judgment
[1987] Q.B. 730, 779:
"To apply the principle in
McGhee v. National Coal Board
[1973] 1 WLR 1 to the
present case would constitute an
extension of that principle. In
the McGhee case there was
no doubt that the pursuer's
dermatitis was physically caused
by brick dust: the only question
was whether the continued
presence of such brick dust on the
pursuer's skin after the
time when he should have been provided
with a shower
caused or materially contributed to the dermatitis
which he
contracted. There was only one possible agent which
could
have caused the dermatitis, viz., brick dust, and there
was
no doubt that the dermatitis from which he suffered was
caused
by that brick dust.
In the present case the question
is different. There are a
number of different agents which could
have caused the
RLF. Excess oxygen was one of them. The
defendants
failed to take reasonable precautions to prevent one of
the
possible causative agents (e.g. excess oxygen) from
causing
RLF. But no one can tell in this case whether
excess
oxygen did or did not cause or contribute to the
RLF
suffered by the plaintiff. The plaintiff's RLF may have
been
caused by some completely different agent or agents,
e.g.
hypercarbia, intraventricular haemorrhage, apnoea or
patent ductus
arteriosus. In addition to oxygen, each of
those conditions has
been implicated as a possible cause of
RLF. This baby suffered
from each of those conditions at
various times in the first two
months of his life. There is
no satisfactory evidence that excess
oxygen is more likely
than any of those other five candidates to
have caused RLF
in this baby. To my mind, the occurrence of RLF
following
a failure to take a necessary precaution to prevent
excess
oxygen causing RLF provides no evidence and raises
no
presumption that it was excess oxygen rather than one or
more
of the five other possible agents which caused or
contributed to
RLF in this case.
The position, to my mind, is
wholly different from that in
the McGhee case where there
was only one candidate (brick
dust) which could have caused the
dermatitis and failure to
take a precaution against brick dust
causing dermatitis was
followed by dermatitis caused by brick
dust. In such a
case, I can see the common sense, if not the
logic, of
holding that, in the absence of any other evidence,
the
failure to take the precaution caused or contributed to
the
dermatitis. To the extent that certain members of the
- 13 -
House of Lords decided the
question on inference from
evidence or presumptions, I do not
consider that the present
case falls within their reasoning. A
failure to take
preventative measures against one out of six
possible causes
is no evidence as to which of those six caused the
injury."
Since, on this view, the appeal
must, in any event, be
allowed, it is not strictly necessary to
decide whether it was open
to the Court of Appeal to resolve one
of the conflicts between
the experts which the judge left
unresolved and to find that the
oxygen administered to Martin in
consequence of the misleading
PO2 levels derived from
the misplaced catheter was capable of
having caused or materially
contributed to his RLF. I very well
understand the anxiety of the
majority to avoid the necessity for
ordering a retrial if that was
at all possible. But having accepted,
as your Lordships and
counsel have had to accept, that the
primary conflict of opinion
between the experts as to whether
excessive oxygen in the first
two days of life probably did cause
or materially contribute to
Martin's RLF cannot be resolved by
reading the transcript, I
doubt, with all respect, if the Court of
Appeal were entitled to
try to resolve the secondary conflict as to
whether it could have
done so. Where expert witnesses are
radically at issue about
complex technical questions within their
own field and are
examined and cross-examined at length about
their conflicting
theories, I believe that the judge's advantage in
seeing them and
hearing them is scarcely less important than when
he has to
resolve some conflict of primary fact between lay
witnesses in
purely mundane matters. So here, in the absence of
relevant
findings of fact by the judge, there was really no
alternative to
a retrial. At all events, the judge who retries the
issue of
causation should approach it with an entirely open mind
uninfluenced
by any view of the facts bearing upon causation
expressed in the
Court of Appeal.
To have to order a retrial is a
highly unsatisfactory result
and one cannot help feeling the
profoundest sympathy for Martin
and his family that the outcome is
once again in doubt and that
this litigation may have to drag on.
Many may feel that such a
result serves only to highlight the
shortcomings of a system in
which the victim of some grievous
misfortune will recover
substantial compensation or none at all
according to the
unpredictable hazards of the forensic process.
But, whether we
like it or not, the law, which only Parliament can
change, requires
proof of fault causing damage as the basis of
liability in tort. We
should do society nothing but disservice if
we made the forensic
process still more unpredictable and
hazardous by distorting the
law to accommodate the exigencies of
what may seem hard cases.
Leave to appeal was given by the
Court of Appeal on terms
that the authority should not seek an
order for costs in this House
or for variation of the orders for
costs in the courts below. For
the reasons I have indicated I
would allow the appeal, set aside
the order of the Court of Appeal
save as to costs and order
retrial of the issue whether the
negligence of the authority, as
found by the Court of Appeal,
caused or materially contributed to
the plaintiff's RLF.
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LORD FRASER OF TULLYBELTON
My Lords,
I have had
the advantage of reading in draft the speech of
my noble and
learned friend Lord Bridge of Harwich and I entirely
agree with
it. For the reasons stated in it I would allow the
appeal and make
an order in the terms proposed by my noble and
learned friend.
LORD LOWRY
My Lords,
I have had the opportunity of
reading in draft the speech of
my noble and learned friend Lord
Bridge of Harwich. I agree with
it and accordingly concur in his
conclusions and in the order which
he proposes.
LORD GRIFFITHS
My Lords,
I have had the advantage of
reading in draft the speech
prepared by my noble and learned
friend Lord Bridge of Harwich.
I agree with it and the order which
he proposes.
LORD ACKNER
My Lords,
I have had the advantage of
reading in draft the speech of
my noble and learned friend Lord
Bridge of Harwich. I agree with
it and the order which he
proposes.
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