Grounds 1 and 3
27It is convenient to consider grounds 1 and 3 together. The issue raised by those grounds is whether the Magistrate was wrong to reject the application of res ipsa loquitur to this case. The plaintiff submits that such a conclusion was not open on the established facts. It was submitted that the Magistrate erred in her finding in respect of the second limb of the foundation due to a misapplication of the relevant test.
28The evidence established that the defendants were in control of the trailer and that the spare wheel was stored beneath the trailer on a rack and held in place by a T-bar and straps. That was the subject of evidence from the mechanic. The mechanic described the trailer as a flatbed trailer that is ordinarily attached to a prime mover. The trailer had been serviced approximately two weeks prior to the accident, at which time no defect was observed and the tyre appeared to be correctly held in place. Services of that kind were undertaken monthly. There was no evidence as to what happened to the trailer in the two weeks since the service.
29The incident itself involved smoke coming from the back of the trailer, a loud bang and the trailer being lifted up in the air. That was the unchallenged evidence of the first defendant. A short time later, the first defendant inspected the trailer and observed the straps to have been "burnt through".
30As to the second limb of the factual foundation, the Magistrate said:
The question in relation to limb two of the test is whether the occurrence was of such kind that it does not ordinarily occur without negligence. Tyres and any other objects from a vehicle do not ordinarily separate from the body of a vehicle and end up in the middle of the road, however, does that mean that such an occurrence does not ordinarily occur without negligence? [emphasis added]
31Her Honour referred to the evidence of the mechanic that no defect was identified by him in the mechanism that held the spare wheel in place. Her Honour referred also to the observations made by the first defendant upon his inspection of the trailer shortly after the incident. She found there was no other evidence as to how the wheel became separated from the trailer, including a lack of expert mechanical evidence.
32Her Honour then made the following remarks:
There may be a number of possible reasons why this occurred. The ropes were faulty, the T-bar was not properly secured, there was a crack in the T-bar. There may have been other external reasons, something on the road that came into contact with the tyre rack causing friction. There may have been a latent defect not discoverable on visual inspection. These are all possibilities but none of them is supported by the evidence before me. They are matters of speculation or conjecture not evidence. How a binding on a tyre rack became loose is not an occurrence within the common knowledge and experience of mankind such that the occurrence is unlikely to occur without the negligence on the part of the defendants. [emphasis added]
33I do not think those remarks reveal a misapplication of the relevant principles. On the contrary, the Magistrate gave proper consideration to the many ways in which an incident of that kind could occur in the absence of negligence on the part of the operator of the trailer. Those were relevant matters to identify in an assessment of the second limb of the factual foundation.
34In my view, it was open to the Magistrate to conclude that this was not an incident of the kind that, in the common knowledge and experience of mankind, does not ordinarily occur without negligence.
35There was little evidence to assist in making the assessment required by the second limb of the factual foundation. The plaintiff, in a case based on res ipsa loquitur, is not required to adduce evidence to rule out all other explanations of the incident. There will be cases, however, where a failure to narrow the possibilities will make it difficult to draw the inference sought. In Schellenberg, Gleeson CJ and McHugh J (at 140 [44]) applied the following statement of Dixon CJ, Webb, Fullagar and Taylor JJ in Mummery at (117):
In other words the question is whether the latter occurrence was such 'as in the ordinary course of things does not happen if those who have the management use proper care'. To that inquiry in this case there cannot be an affirmative answer. We are told nothing of the characteristics of circular saws and we are not told that such an occurrence is usual or unusual or indeed highly improbable. Moreover we are told nothing concerning the size of the piece of wood in question and it is difficult, if not impossible, in these circumstances to attribute the accident to some act of negligence on the part of the operator. If the question is posed 'Was the accident such as in the ordinary course of things does not happen if those who have the management use proper care?' the answer, on the evidence in the case, must be 'We simply do not know.' One may but conjecture but cannot as a matter of inference attribute negligence to the defendant's foreman. [emphasis added]
36Similarly, in Kasupene v Ajax Foundry Pty Ltd [2006] NSWCA 309, the plaintiff was injured when a heavy tray being lifted by an overhead crane fell on his foot. The plaintiff's case relied upon the trial judge drawing an inference of negligence upon the basis of res ipsa loquitur. In relation to the second limb of the factual foundation, McClellan CJ at CL (as his Honour then was) said:
To my mind the principle has no application to the present case. Although the ordinary person well appreciates that a load being lifted by a crane should not fall onto a person's foot the cause of the event is a matter about which the ordinary person would have little if any understanding. There may be, as the trial judge identified, many reasons why such an event occurs without negligence of the operator. Without any evidence which could allow those other possible explanations to be put aside it is not possible to infer that it was a negligent act of the defendant for which it was liable, which caused the accident. [emphasis added]
37The same may be said of the present case. This was a case in which other possible causes could not be ruled out. There were a number of reasons why the wheel may have become detached. To infer that it became detached because of the negligence of the defendants assumes that one or more of those explanations are more probable than the others. There was no basis for such an assumption on the evidence: see Schellenberg at 175 [150] per Hayne J.
38The plaintiff relied on a series of authorities to support a conclusion that objects do not ordinarily fall from moving vehicles unless the driver is negligent. I do not think those cases assist.
39In Bellizia v Meares [1971] VR 641, a man was injured when he was struck by a bale of wool that fell from a truck. In a trial before a judge and jury, the judge refused to direct the jury that it was open to them to draw an inference of negligence upon the basis of res ipsa loquitur. On appeal to the Full Court of the Supreme Court of Victoria, this was held to be erroneous. The Court stated (at 644):
The authorities we have cited show that in the absence of an explanation for the fall of the bale which the jury accepted, the case was one to which the doctrine of res ipsa loquitur was applicable, and it called, we think, for a clear direction that, in those circumstances, it was open to the jury to find negligence on the part of the defendant from the fact that it fell from the semi-trailer and struck the applicant. [emphasis added].
40It does not follow that the jury was obliged to apply the principle.
41The plaintiff also relied on the decisions in Incorporated Nominal Defendant v Knowles [1987] VR 138, Nominal Defendant v Genn [2004] NSWCA 306 and Government Insurance Office of NSW v Best (unreported, 2 June 1992, New South Wales Court of Appeal). None of those authorities establishes that an inference of negligence must be drawn in all cases where an object falls from a motor vehicle in unexplained circumstances. They merely indicate that such an inference will usually be open in such circumstances. The ultimate inference or lack of inference drawn will depend on the facts of a given case and the other evidence: Franklin v Victorian Railways Commissioners at 201 per Dixon CJ; Anchor Products Ltd v Hedges at 500 per Windeyer J.
42The Magistrate, after hearing all the evidence, was disinclined to draw an inference of negligence. It cannot be said that an inference of negligence was the only inference available on the facts. Even if the incident was within the common knowledge and experience of mankind (which is doubtful), there were other inferences available on the facts that did not involve negligence on the part of the defendants.
43In my view, grounds one and three must be rejected.