Before the elaborate statutory provisions now in force in the United Kingdom and Australia relating to the conduct of elections, a breach of any of which may entail the invalidity of the election, were enacted, the grounds on which the validity might be impeached were practically confined to cases in which such influence was brought to bear upon large bodies of the electors as to justify the belief that the choice was not free and deliberate. (I remark, in passing, that the invalidity of an election for non-compliance with such statutory provisions is not usually declared by Statute, but is left to follow from the application of the common law of elections.) The principal grounds for impeaching an election at common law in the United Kingdom were undue influence, intimidation, general corruption, and riotous disturbance during the election. Each of these cases gave rise to the application of the same general rule, which was afterwards applied by the Courts to breaches of statutory provisions regulating elections. If either of these conditions was shown to have prevailed to such an extent as to be likely to have affected the freedom of choice, the election was declared void. It is manifest that in such cases it was generally impossible to prove affirmatively that the result of the election was affected. It was therefore always held sufficient to establish that the extent of the improper practices or other disturbing elements was such as to show good ground for believing that the final result might probably have been affected. The extent of the corrupt or illegal practices was, consequently, a material point. It is evident, for instance, that if the successful candidate had a majority of 500, and the evidence of intimidation or undue influence was limited to 50 persons, the freedom of choice of the whole electorate was not likely to have been affected. This was very clearly pointed out by Bramwell B. in the North Durham Case[2]: - "I take it that the law is this: first of all, there is the statutory intimidation, that contemplated by the Statute, if one may use such an expression, that is, an intimidation contemplated by the Statute which avoids the seat, where a candidate or his agent is guilty of it. But besides that there is another intimidation that has been called a common law intimidation, and it applies to a case where the intimidation is of such a character, so general and extensive in its operation that it cannot be said that the polling was a fair representation of the opinion of the constituency. If the intimidation was local or partial, for instance, if in this case it had been limited to one district, as Hetton is, I have no doubt that in that case it would have been wrong to have set aside this election, because one could have seen to demonstration that the result could not possibly have been brought about by intimidation, and that the result would not have been different if it had not existed. I do not mean the result of the polling in that particular district, but the general result of the majority for the respondents. But where it is of such a general character that the result may have been affected, in my judgment, it is no part of the duty of a Judge to enter into a kind of scrutiny to see whether possibly, or probably even, or as a matter of conclusion upon the evidence, if that intimidation had not existed, the result would have been different. What the Judge has to do in that case is to say that the burden of proof is cast upon the constituency whose conduct is incriminated, and unless it can be shown that the gross amount of intimidation could not possibly have affected the result of the election it ought to be declared void. Now in questions of this sort one must look not only to the amount of intimidation, but to the absolute majority which has been obtained. It was the opinion of Mr. Justice Willes, and I believe it is not inconsistent with the opinion of Mr. Justice Keogh, as expressed in that celebrated and most useful judgment which he gave in the Galway Case, that you are to look at the probable effect of intimidation, which consists of two things, the extent and operation of the intimidation, and the majority which the sitting members got. Now, I think if it were otherwise, and if one were told that partial intimidation would avoid an election, although it were certain that it had not affected the result of the election, the consequence would be that a few mischievous persons might upset every election. On the other hand, if one were inclined to go into a kind of scrutiny the consequence would be that one might make a very great many mistakes; besides, I am of opinion that, where there has been so large an amount of intimidation that it is uncertain whether the result would have been the same without it, it cannot be said that the election was free, or that it represented the real opinion of the constituency, but that it must be held void on account of that uncertainty."