Cr App R 31
at paragraphs 88, 89 and 90). The Court of Appeal endorsed Boreham J's direction in Bracewell. In that case the defence raised the possibility that the victim had been strangled, recovered and then suffered a heart attack, a sequence of events which could not be ruled out as a matter of scientific certainty. The judge directed the jury not to judge the case scientifically or with scientific certainty but to decide whether, on the whole of the evidence, they were sure. The Court of Appeal endorsed that direction which correctly drew the distinction between scientific proof and legal proof. It pointed out that the medical evidence was only part of the material on the basis of which the jury had to reach a decision.” 98.This extract demonstrates the hypothetical nature of the alternative cause of death being considered in Gian and also in Bracewell. It illuminates the reality that in many homicide cases determining the cause or causes of death does not rely exclusively on expert opinion but can be collected from surrounding circumstances. 99.Professor Deakin was not asked to consider hypothetical alternative causes of death of the sort canvassed in Gian and the cases therein cited. There were two concurrent causes of death in issue: first, the effect of the drugs taken by Louella and secondly want of medical attention after the time when her condition became obviously critical. There was no evidence beyond that of Professor Deakin of a non-expert nature which could help answer the relevant question. 100.It is unhelpful to attempt to contrast scientific certainty (put at 100%) with a different figure for legal certainty. Human beings asked the question whether they are sure of something do not think in those terms. In the context of causation in this very sad case the task of the jury was to ask whether the evidence established to the criminal standard that, with medical intervention as soon as possible after Louella’s condition presented a serious and obvious risk of death, she would have lived. In short, had the prosecution excluded the realistic possibility that, despite such treatment, Louella would have died? 101.In our judgment none of Professor Deakin’s descriptive language achieved that. Even his description of a 90% chance of survival at 21.10, were medical help available, leaves a realistic possibility that she would not have lived. 102.Misra is a different case. The evidence in support of causation needs careful attention. The case is not authority for the proposition that causation is always a matter for the jury whatever the underlying evidence. No issue should be left to a jury unless there is sufficient evidence upon which it can be satisfied so it is sure. It is true that the two prosecution experts who gave evidence on causation spoke in varying descriptive language, including the balance of probabilities. That said, amongst the evidence by one expert was that he was “as certain as one can be he would have survived”. There was evidence of the general statistical chances of dying from the relevant condition even with appropriate medical treatment (contested but coalescing around 5%); but at two points in the judgment (paragraphs 21 and 74) there is reference to the view of one of the experts that the fact that the victim was a 31-yearold man in otherwise good health was a factor which reduced his statistical chance of dying and that he was in fact doing well before the negligence supervened. 103.In our view, this is one of those rare cases (as was Morby) where the expert evidence was all that the jury had to assist them in answering the question on causation. That expert evidence was not capable of establishing causation to the criminal standard. Miss Darlow’s final submission that at 21.10 Louella was deprived of a 90% chance of survival was an accurate reflection of Professor Deakin’s evidence but, for the reasons we have explained, that is not enough. Put another way, if an operation carried a personal 10% risk of mortality, both patient and clinicians would be able confidently to say that the chances of survival were very high or very good (to take two phrases used by the Professor) but none could be sure. 104.In respectful disagreement with the judge, we conclude that the appellant’s main argument, that the case should have been withdrawn from the jury, is established. Applying the Galbraith test (R v. Galbraith [1981] 1 WLR 1039), taken at its highest, the evidence adduced by the prosecution was incapable of proving causation to the criminal standard of proof. The appeal against conviction for manslaughter must be allowed.