11. There are several problems with this analysis. First, it is based upon the stopping distances set out in Leslie & Britts which are no more than averages. The tables themselves make it plain that the figures may not be applicable in a particular instance. In this case there was no apparent allowance by the primary Judge for any delay by the appellant in applying his brakes. Nor was there any allowance for the effect of the appellant's vehicle having partly left the roadway (a matter which the primary Judge properly excused on the basis that it occurred on the 'agony of the moment').
12. In our view it is clear that the tables could only be relied upon if there was expert evidence explaining how the tables could be applied on the facts of this case. There was no such evidence before the primary Judge. It is clear from the transcript that the appellant objected to the use of the tables in the manner in which they were used. In the absence of such expert evidence or (perhaps) the agreement of the parties, the primary Judge could not rely upon the tables as evidence of stopping distances. The respondent conceded in argument before us that the tables could not be used in the manner in which the primary Judge did use them.
13. The consequence is that the conclusion by the primary Judge that the appellant's vehicle was travelling at 135-140 kilometres per hour cannot be sustained. There was no evidence to support that finding. There was no evidence to support any finding that the police vehicle was doing more than 110 kilometres per hour.
14. This does not mean that the matter should be remitted for further hearing. Neither party asked the Court to do that. Both parties requested that this Court make its own assessment of whether the parties had been negligent and, if so, to what extent, based upon the evidence that was before the primary Judge. There are obvious dangers in doing so: see Suvaal v Cessnock City Council [2003] HCA 41; (2003) 200 ALR 1 at 18-20. However, in this case there were no credibility findings against any particular witnesses. In this case the evidence is not significantly in dispute. The question that is in dispute is what inferences can be drawn from that evidence. This Court is in as good a position to draw those inferences as was the primary Judge: see Warren v Coombes [1979] HCA 9; (1979) 142 CLR 531.
15. What evidence there was, was that the appellant's vehicle was travelling at between 100-110 kilometres per hour immediately before the collision. Constable Clark gave evidence that the traffic was heavy and that it was travelling slowly. The evidence of the speed of the traffic in the other three lanes of Adelaide Avenue was that it was travelling at between 30 and 40 kilometres per hour. It was clearly less than the 80 kilometres per hour that is permitted at the place where the accident occurred. This reflects what was the practical reality at the time the collision occurred. The bushfire had caused considerable disruption to traffic. Some distance prior to the point of collision, the traffic on the western lanes of Adelaide Avenue was being diverted to the eastern lanes by reason of the fire. The police officers gave evidence that at that place traffic was crossing the median lane and entering the bus lane.
16. It was not disputed before the primary Judge that the appellant was exempt from the ordinary statutory road rules pursuant to Regulation 69 of the Road Transport (Safety and Traffic Management) Regulations 2000 (Regulation 69). That regulation relevantly provides that the usual statutory requirements in relation to speed limits, compliance with road signs and so on do not apply to a police driver if, in the circumstances, the driver is taking reasonable care and it is reasonable that the driver be exempt and, if the vehicle is moving, it is displaying a red or blue flashing light or sounding an alarm. The result of that exemption was that the appellant was not subject to prosecution for exceeding the speed limit or for driving in the bus lane. Of course, the exemption must be understood as an exemption from criminal liability. In particular, the reference in Regulation 69 to "reasonable care" must be understood in that context.
17. The appellant accepted that the exemption from the statutory road rules did not have the consequence that the appellant was necessarily exempted from liability for negligence. The appellant was correct to make that concession. It is well supported by authority: see, for example, South Ambulance Ambulance Transport Inc v Wahlheim [1948] HCA 32; (1948) 77 CLR 215 (Wahlheim); Board of Fire Commissioners (NSW) v Ardouin [1961] HCA 71; (1961) 109 CLR 105; Morgan v Pearson (1979) 22 SASR 5; Patterson v McGinlay (1991) 55 SASR 258, 266-267; Nelligan v Mickan [1998] SASC 6935; (1998) 28 MVR 114 (Nelligan).
18. Nevertheless, the appellant submitted that his driving had not been negligent on this occasion. In this regard the issue is not whether the appellant owed a duty of care to the respondent and to other road users. Plainly he did. The question is whether that duty was breached. This involves consideration of the extent or nature of the duty owed.
19. It is clear on the authorities that Regulation 69 reflects the community expectation that the drivers of police vehicles may, in appropriate circumstances, take risks that others cannot. In our view it is wrong in principle to analyse the duty of care of a driver exempted under Regulation 69 in exactly the same way that the duty of care of an "ordinary" driver would be analysed: contrast Johnstone v Woolmer (1977) 16 ACTR 6; Schulz v Morrison (1984) 1 MVR 34. In relation to an exempt driver it is necessary to balance the risk involved in the method of driving against the end for which the exemption has been given: see Watt v Hertfordshire County Council [1954] EWCA Civ 6; [1954] 2 All ER 368 at 371; Blight v Warman & McAllan [1964] SASR 163 at 170.
20. On the other hand, the driver of an exempt vehicle cannot ignore the risk of the method of driving: see Wahlheim at 222. There will be some circumstances where the very danger that provides the basis for the exemption from the ordinary statutory rules, will also have the effect that driving at the ordinary speed limit is negligent: see, for example Nelligan where the driver of an emergency vehicle travelling at 60 kilometres per hour in an attempt to escape from a bushfire was found to be negligent in colliding with a stationary emergency vehicle.
21. The correct approach is to ask what a reasonable person in the position of the police officer would do, having regard to the information which the police officer either knew or ought to have known. The common law in this regard is now reflected in s 42 of the Civil Law (Wrongs) Act 2002 (ACT) (Wrongs Act). In considering the extent of the duty owed in these circumstances a reasonable person can be expected to make a reasonable assessment of the risks: see for example, the discussion by Higgins J in Winter v Cth (1992) 112 ACTR 10 at 27-28.
22. In this case the relevant circumstances of which the appellant was aware, or should have been aware included: