The softer or relatively softer shoulder
131 What did the trial judge mean by the shoulder, and what did he mean in describing it as softer or relatively softer?
132 A road engineer's distinctions between the shoulder of the road and the formation beyond it, on the one hand, and the shoulder of the road and travelled way, on the other hand, were understandably not maintained in witnesses' descriptions of the road. The rill seems often to have been taken to be part of, or at the least not distinguished from, the shoulder, and as I have said sometimes the word seems to have been used to refer to, or include, loose material on the shoulder. The shoulder was treated as something other than the central part of the road, which was given many descriptions - for example, the running track, the running surface, the hard road, the hard stuff, the hard part where the trucks ran all the time, the hard surface, or the "roadway itself". Mr Bates referred to "the main part of the road, the part you would normally drive on, the hardest, the clean part of the road", and distinguished it from "out to the rill". The shoulder was often referred to as such, although without precision, but also in other ways, for example as "out further" or "the edge part".
133 As has been seen, the trial judge referred at [18] to the central and heavily compacted portion of the road approximately 8 metres wide, and at [261] to "the hard compacted surface" of the road. Consistently with the witnesses' language, this was not identification of the travelled way according to the engineering drawings. It can be better understood from the trial judge's finding at [232] that there was "no loose gravel on the central compacted surface of the relevant part of the road of sufficient size to give rise to the effect of marbles on that hard surface". In short, the trial judge's reference to "where the shoulder began" (at [261]) was not according to the engineering drawings, although there may have been a rough correspondence, but from the usage of the road.
134 Many witnesses were asked about a soft shoulder. It was often not clear whether the questioner or the witness meant the softness of the heaped-up rill, softness from the presence of loose material on a firm shoulder, or softness because a shoulder less compacted than the central part of the road could give way under a vehicle's wheels.
135 In relation to the road in general, there was evidence of softness in all these senses. Illustrations are -
Mr James McIver, that he had seen sections of the road "as one approaches the rill" that had been "damaged by truck wheels that had broken the surface"; he distinguished between "the running surface" and "the soft area along the edge";
Mr John Jellick, that the shoulders "would stand up to a truck running on them without sinking or anything but they are not part of the running track", but depending on "how far out on the rill" the road train went it could "break through";
Mr Comiskey, that the shoulders were not soft but there would probably be loose material along the edge; he distinguished between "the hard stuff" and where the surface was "softer than the central part of the road"; he also said that he had seen deep indentations in the shoulder left by a truck;
Mr Bates, that the road still had a hard surface on the outside but had "fall-out", loose little bits of coal on top of the road, and was "the same compaction but a little bit slippery once you get outside the main running area of the road";
Mr O'Loughlin, that "the main travel road" was hard and had been compacted "and the softer area is the off-shoots from the grading material, so you can see small pebbles of different size";
Mr Majlinger, giving as one reason for the respondent's loss of control that her vehicle went too far out on the "marbles", a racetrack expression meaning "there is little bits of rolled-up rubber or little bits of debris or fine gravel";
Mr Rawlins, that the road was equally compacted from rill to rill "for all intents and purposes", as seen in Exhibit 3; and
Mr Barry Jellick, that "the edges or shoulder which extended beyond the guideposts tapering towards the table drain were solid", which he knew not only from driving on the shoulders but also from walking on them when he had to replace guideposts dislodged through the grading process.
136 These are but illustrations: there was great variety, and it is not profitable to multiply them. It is clear, however, that road trains passing each other would move onto the shoulders, and that while there were occasions when on going close to the rill they could "break through" the shoulders generally bore their considerable weight.
137 The trial judge was referring to the shoulder at the location of the respondent's accident. I return to the tyre mark on the western shoulder: the trial judge's treatment of the tyre mark shows what he meant by a softer or relatively softer shoulder.
138 Early in the reasons was his Honour's statement at [19], set out above, that "[t]he tyre marks on the roadway depicted in the photographs show that the surface of the shoulder on the western side was sufficiently dusty to allow the marks of tyres to remain but not sufficiently soft to permit a tyre to penetrate the road surface". The trial judge had referred in the preceding paragraph to the photographs Exhibits 4 and 5, but only Exhibit 4 showed the western shoulder. As will be seen, he later referred specifically to the photographs Exhibit 3 and 4.
139 The trial judge later referred, under the heading "The Events of 19 September 1998", to evidence given by a number of witnesses. They included descriptions of the tyre marks on the road, not only those on the western shoulder, given by Mr Bates, Mr Shannon, Mr Majlinger, Mr Comiskey, Mr O'Loughlin, Senior Constable Turner, Mr Ross, Mr Barry Jellick, Mr John Jellick and Mr Rawlins.
140 Although the trial judge's account did not reflect it, Senior Constable Turner's evidence seemed to have both the near side and driver's side wheels of the respondent's vehicle off "the road surface", and he said that the vehicle "went over the rill". It was rather confused evidence, amongst other reasons because he considered that the rill and the shoulder were the one and the same. He was the odd man out, and I think he was implicitly not accepted by the trial judge.
141 I summarise the other descriptions of the tyre mark in the evidence which the trial judge recounted. Mr John Jellick said that the tyre mark may have touched the rill at one point. Mr Bates said that it went off "the road" about a metre, and did not go on the outer (or western) side of the rill; it went to about half a metre from the rill, and was then "trying to rejoin the road". Mr Majlinger said it appeared that the vehicle had been "on the marbles" at the extreme western edge of the road surface, and that the surface there was "hard but with loose stones on top, fine pebbles or whatever". Mr Comiskey said there were wheel tracks from the near side wheels on the shoulder. Mr O'Loughlin saw wheel tracks "veering from the road on the shoulder", and in a note on a photograph said that the wheels were "on the soft ground". Mr Ross said that the marks showed the vehicle veering off from the hard surface towards the edge. Mr Barry Jellick saw the left hand tyre marks probably a tyre width away from the top of the shoulder off the road surface, they appeared to come off the road gradually. Mr Rawlins could trace the near side wheel tyre mark along the shoulder of the road for about 30 metres.
142 At a later point in his reasons the trial judge referred, with apparent acceptance, to Mr O'Loughlin's evidence that the tyre mark went a maximum of about 75 centimetres off "the road". The trial judge did not refer to Mr Rawlins' recreation of the tyre track in late October 1998, as shown on the photographs part of Exhibit 32, although he did say that photographs were taken on that occasion.
143 Returning to the evidence which the trial judge recounted, Mr Bates said that the outside edge of the road was still hard but had loose little bits of coal on top of the outside edge of the road. The trial judge noted that Mr Bates agreed that the western shoulder was not actually slippery but it was loose. As in the earlier summary, his Honour referred to Mr Majlinger saying that it appeared that the vehicle had been "on the marbles". Mr Shannon said that the tyre marks "didn't stand out until you got close to the post", and the trial judge referred to his explanation that between the heavily compacted area and the rill was an area compacted only by the rubber tyred roller towed behind the grader. Mr Barry Jellick said that there was "dusty, loose material" on the western shoulder where he saw the tyre marks. Mr Rawlins described the shoulder of the road as firm and hard, although at this point Mr Rawlins appears to have meant by the shoulder the batter down to the table drain.
144 The trial judge's references to the evidence in these respects clearly underlay his findings of how the respondent's accident occurred, at [167]-[168] earlier set out. At a later point in his reasons he said, all but repeating what he had said at [19] -
"260 The tyre marks on the roadway depicted in the photographs exhibits 3 and 4 show that the surface of the shoulder on the western side was sufficiently dusty to allow the marks of tyres to remain but not sufficiently soft to permit a tyre to penetrate the road surface."
145 While there were not explicit findings, I consider his Honour to have found that when the near side wheels of the respondent's vehicle went off the central and heavily compacted part of the road and onto what was, in distinction, called the shoulder, they did not touch the heaped-up rill. They ran along the shoulder inside the rill. From his Honour's references to gravel and dust and a dusty surface, I take his Honour to have meant by the soft shoulder or the relatively soft shoulder that there was loose material on a surface which, although not heavily compacted like the central part of the road, was firm and did not break through when the respondent's vehicle (which was of course very much lighter than a road train) went onto it.
146 As the trial judge did explicitly find, the shoulder was "not sufficiently soft to permit a tyre to penetrate the road surface". The relevant softness was not in lack of compaction of the shoulder, but because of the loose material, the gravel and dust, on the firm surface of the shoulder.
147 Findings so understood were in my view proper findings on the evidence, and to the extent to which the respondent contended for a different understanding of the trial judge's reasons - which was far from clear - I would not accept her contention. There was other evidence to like effect. It included Mr Barry Jellick describing tyre marks in loose material on top of a hard surface; and saying that on the day of the accident he walked over on the shoulder "and it was solid. The only loose material was on the shoulder where the vehicle had skidded"; Mr John Jellick saying that the area "beyond the edge of the road, bounded by the guidepost" was firm, with "some loose material on the shoulder for a distance of about 1 metre, beyond the white guide post"; Mr Comiskey saying that there were not troughs or indentations but just impressions of the wheel where the surface was softer than the central part of the road; and Mr Rawlins saying that where the tyre track was seen was similar in compaction to the "pavement" in a practical sense and the tyre marks were with in the "dusty material", the "gravel which exists on the shoulders". While Mr O'Loughlin referred to a soft shoulder and said that he "observed that [the respondent's] wheels had gone into soft ground", his evidence is consistent with a tyre mark in loose, and therefore soft, material on the shoulder.
148 Further, the understanding of what his Honour meant by the softer or relatively softer shoulder is consistent with, perhaps required by, the mechanism for loss of control found by the trial judge, namely loss of traction (at [167]) or the differential adhesion of the wheels (at [267]). There can be loss of traction or of adhesion due to loose material. It is not obvious that, and we were not referred to evidence supporting that, it could come from a tyre's penetration of an insufficiently compacted surface.
149 It should be said that there was little, if any, difference between the appellants and the respondent in relation to the position of the tyre track for the 33.3 metres prior to the deviation to the right. I have referred to Mr Rawlins' evidence that the tyre tracks shown in photographs in Exhibit 32 were approximately where he remembered the tracks were. Although there was some dispute over arcing or straightness of the tyre track, the appellants accepted that the tyre track on the western shoulder of which many witnesses spoke was approximately in that location and direction, and the respondent's counsel said that "we do not differ from the path - we don't differ greatly anyway - from the path as shown by Mr Rawlins".
150 The tyre track in the photographs is in what appears to be loose material approximately mid way between a clean and compacted surface over the central part of the road and the toe of the rill. A vehicle on the path shown by the tyre track would be headed directly for the guidepost. This last is consistent with the evidence of Mr Barry Jellick (to which the trial judge referred) that, if the vehicle had not changed its course, it would have "run the guidepost over". Mr John Jellick gave evidence to the same effect, also saying that "she would have hit to the right of centre of the bonnet, the right of centre of the vehicle". So did Mr Rawlins: he said that from the tyre marks the vehicle "would have taken out the guidepost" with the point of impact in the centre of the radiator.