One of the grounds urged on his behalf to this Court on that occasion was that the learned Judge before whom the case was tried misdirected the jury on a fundamental point. It is at the root of our law that every man accused of crime is presumed to be innocent until proved to be guilty, and that no one shall be found guilty unless the jury are convinced of his guilt beyond reasonable doubt. And it was urged that the summing-up to the jury failed in this essential matter. That point had not been taken before the Supreme Court of New South Wales, and no decision was given upon it. After consideration, this Court granted leave to appeal, in general terms, for argument without excluding that ground. On the appeal itself, the appellant's counsel were permitted to argue the question, subject to the prior question whether, in view of the point not having been raised in the Supreme Court, this Court had jurisdiction to determine it, one way or the other. Both branches - merits and jurisdiction - were fully argued. No conclusion is arrived at by this Court upon the question of our jurisdiction, and therefore no authoritative decision can be given on the main question, but, for the purposes of this case only, opinions are stated as if we had jurisdiction. The difficulty as to the misdirection complained of occurred in this way: - Several times during the summing-up the learned Judge told the jury they must not convict the prisoner unless they were persuaded of his guilt beyond all reasonable doubt. So far, no fault could legally be found. The subject of reasonable doubt is dealt with in Brown's Case in the judgment of Barton J.[4] and in the judgments of Isaacs and Powers JJ.[5]. We think the opinions there expressed correctly state the law, and we find it necessary to form our opinion on that point in order to consider the further point as to miscarriage. Of course, neither Brown's Case nor this case can be legally regarded as a formal decision on the question of reasonable doubt, or miscarriage by reason of a faulty charge on that point. But if the fate of the accused is to be determined by extra-judicial opinion, our own is clear that, though the language of the charge in Brown's Case was different from that in this case, the principle there stated, which now represents the opinion of four Judges of this Court, applies to the present case, and that is the real test. We summarize the law as there laid down, so far as relevant to the circumstances of this case. Reasonable doubt as to a prisoner's guilt means reasonable doubt entertained by the jury as actually constituted, after considering the circumstances of the particular case. Eminent Judges have explained that to mean that the jury must have what is termed "moral certainty" of the prisoner's guilt. Of course, physical or demonstrable certainty is impossible. But our law draws a great distinction between civil and criminal cases. In civil cases, you decide merely on the balance of probabilities; in criminal cases, you must be "morally certain" that the prisoner is guilty. This is elementary. In the ordinary affairs of life a man acts on what seems to him, on the whole balance of probabilities, the reasonable thing to do. But in the most serious affairs of life he hesitates longer: and the more serious the affair, the longer he hesitates, and the less doubt must he have before he acts. And this truth is at the root of the point raised for the appellant. If that point be sustained, we cannot understand how it can fail to amount to a substantial miscarriage of justice. It may, for all we know, have been the turning point in the jury's mind. But this much is clear, we are neither the tribunal to decide on the prisoner's guilt - that would be usurping the jury's function; nor are we able to say the jury would certainly have come to the same verdict if the misdirection had not occurred. And this is the test. A miscarriage of justice takes place in a criminal case whenever there is some departure from strict law or from an established practice designed to protect a man possibly innocent, unless the Court can say positively that the verdict would have been the same. As Lord Alverstone said in R. v. Dyson[6]. "it is one thing to say that the jury on a proper direction would probably have so convicted; it is another to say positively that there has been no substantial miscarriage of justice." This was the principle laid down and acted upon by the House of Lords in Bray v. Ford[7] even in a civil action for damages. Therefore, according to the highest authority, if there has been a substantial miscarriage of justice, supposing there was the misdirection complained of, we have to inquire as to that. The learned Judge, although several times he referred merely to reasonable doubt, which, if left alone, is supposed to carry its own meaning, proceeded on one occasion, unfortunately for the prisoner, to define what he meant all along when he used the term "reasonable doubt." He said this: "A reasonable doubt is a reasonable doubt such as reasonable men, men of affairs going about the ordinary life of the world, would have." That is the interpretation of the phrase "reasonable doubt" which the jury were told to accept whenever that term was used. And it carries the more weight because it was the final direction given as to that term. What, then, is the effect of putting in the expression "men of affairs going about the ordinary life of the world"? Would not - or might not, for that is sufficient - might not a jury naturally think that means such a doubt as a business man would have when transacting his ordinary affairs? We go so far as this in defence of human life: if that definition be open merely to fair doubt as to whether it means what we think it clearly means, if the jury might reasonably take that to be its meaning, that is sufficient, in our opinion, to entitle the accused to a new trial. Courts of Criminal Appeal were instituted to enable the corporate conscience of the community to be satisfied that by no mischance an innocent person is condemned. The guiding principle of English criminal law is a humane one: it is that, while guilt once established should be punished, yet it is safer to err in acquitting than in condemning, and that it is better that many guilty persons should escape than one innocent person suffer. But we think the interpretation given to the jury is clearly wrong. And the reason we think it wrong is this: "a man of affairs going about the ordinary business of life" does not look for "moral certainty." Men of affairs going about the ordinary business of life could not afford to wait for "moral certainty," which, as stated by high authority, is the affirmative form of stating the absence of reasonable doubt in criminal cases. A merchant transacting an affair of ordinary life comes to a conclusion without reasonable doubt, on much more slender consideration than if, for instance, he were weighing the matter of undergoing a severe operation either by himself or by some one dear to him. In other words, "reasonable doubt" in the circumstances which would deter him from acting in the ordinary life of the world would have to be much more pronounced than if the matter had more serious consequences. Some Judges have impressed juries with their duty to be convinced as they would require to be convinced in their graver and more important affairs. That is nearer the mark, because the results of a criminal conviction certainly belong to the graver and more important matters of life. But how can a jury, having to determine the guilt of the accused in such a case as the present, where not merely character and liberty but life itself are at stake, be properly told to place themselves for that purpose in the same position as "men of affairs going about the ordinary life of the world," and told that a doubt that would be reasonable in the one case is a reasonable doubt in the other, and therefore that a doubt that would not deter them from acting in ordinary life - (say) the purchase of wheat or butter - would not deter them from sending a fellow creature to death? An error, a serious and fundamental error, in our opinion, has been made. A false analogy, a wrong standard, was supplied to the jury; one which lessened their sense of responsibility. Test it by a simple and very practical process, and one that brings the matter home better than any amount of theoretical argument. Which of us, if we were standing in peril as the appellant was, would not feel the vast and vital difference between the two standards - the chances that a business man thinks reasonable in the ordinary life of the world, and the moral certainty that the law requires in conviction for crime? In our opinion, an unfortunate but unmistakable miscarriage of justice has occurred, that can only justly be remedied by a new trial.