I find that the wall collapsed as a result of the combined operations of three factors. One was that the trench had been dug along the whole of its length to a level below the bottom of the footings of the plaintiffs' wall. The second was that the pockets had been dug under the wall in a fashion which was grossly unskilled, and the third was, of course, the rain. If the trespass was, as I find it was, a significant contributing cause of the ultimate damage, then in point of law that ultimate damage is regarded as a consequence of the trespass and the trespasser is liable.
The judge relied on a passage from the decision of Cockburn C.J., Mellor and Field JJ. in Bower v. Peate [3] :
The answer to the defendant's contention may, however, as it appears to us, be placed on a broader ground, namely, that a man who orders a work to be executed, from which, in the natural course of things, injurious consequences to his neighbour must be expected to arise, unless means are adopted by which such consequences may be prevented, is bound to see to the doing of that which is necessary to prevent the mischief, and cannot relieve himself of his responsibility by employing some one else - whether it be the contractor employed to do the work from which the danger arises or some independent person - to do what is necessary to prevent the act he has ordered to be done from becoming wrongful. There is an obvious difference between committing work to a contractor to be executed from which, if properly done, no injurious consequences can arise, and handing over to him work to be done from which mischievous consequences will arise unless preventive measures are adopted.
He then continued:
The Court in that passage was putting aside the provision in the contract under consideration by which the builder undertook the responsibility for support and was simply saying that the situation was one in which the building owner could not relieve himself of responsibility by making a contract with someone else. That case was itself a case involving the right of support between adjoining land owners. It was wholly approved in the famous case of Dalton v. Angus [4] . See also Johns v. Delaney [5] .
The learned primary judge then said:
But the classification of the contract I think is a matter of fact not to be determined simply by reference to authority. In the present case, judging the situation as well as I am able to do as a layman, and using such experience as I have in this class of matter, and using the undisputed evidence of Dr. Allen, I would have no hesitation in classing the situation and the contract which I have to deal with here, as a situation and a contract from which mischievous consequences would arise unless preventative measures were adopted. The result of that classification is that the landowner whose enterprise it was that gave rise to the loss is liable.
1. (1876) 1 Q.B.D. 321, at p. 326.
2. (1881) 16 App. Cas., at p. 791.
3. (1890) 16 V.L.R. 729.