JUDGMENT OF: Crawford CJ, Tennent and Porter JJ

Evidence - Admissibility and relevancy - Opinion evidence - Expert opinion - Qualifications of witness.

R v Bjordal [2005] SASC 422; (2005) 93 SASR 237, Makita (Aust) Pty Ltd v Sprowles [2001] NSWCA 305; (2001) 52 NSWLR 705, followed.

R v Murphy [1980] QB 434, R v Oakley [1979] RTR 417, R v Bonython (1984) 38 SASR 45, Clark v Ryan [1960] HCA 42; (1960) 103 CLR 486, referred to.

Evidence Act 2001 (Tas), s79.

Criminal Law - Evidence - Judicial discretion to admit or exclude evidence - Prejudicial evidence - Generally.

Festa v R [2001] HCA 72; (2001) 208 CLR 593, followed.

Evidence Act 2001 (Tas), s137.

Judgment Number: [2010] TASCCA 18

Appeal and application for leave to appeal dismissed.

1 In July 2009, the appellant was tried for manslaughter before Slicer J and a jury. The charge concerned the manner in which he drove a red Ford Falcon sedan northwards on Natone Road on 21 March 2008. It collided with a motor cycle travelling in the opposite direction. The rider was killed. The appellant was found guilty and sentenced to imprisonment for five years from 29 July 2009, with a non-parole period of three years and three months, and disqualified from driving, effectively for eight years from the date of the sentence.

2 He appealed against his conviction asserting errors of law by the learned trial judge in admitting evidence. He also sought leave to appeal against his conviction on the ground that the verdict was unsafe and unsatisfactory having regard to the evidence and the fact that there was no evidence of what the notice of appeal refers to as "the critical speed" of the corner where the accident occurred.

3 The accident happened on a sweeping right hand bend when viewed by the appellant. Visibility around the bend was severely limited. The speed limit in the area was 100 kph. He was heading north through a country area that had some houses. The Crown's case was that he was driving at an excessively fast speed over a distance of about 12 kilometres leading up to the accident. He drove around a left hand bend and then into the right hand bend. The Crown's case was that he lost control as a consequence of driving at an excessive speed and his vehicle commenced to yaw prior to the right hand bend, with its front moving to the right and over the centre of the road, so that it crossed onto the incorrect side of the road and collided with the motor cycle and its rider. The impact to his vehicle centred on the left front door. It was apparent that his vehicle was at an angle across the road at the moment of impact for it to have been centred there.

4 The appellant gave no evidence at the trial but the jury had a recorded interview between him and the police to consider. In it he said that as his vehicle entered the right hand bend at about 70 or 80 kph, it was on its correct side. He saw the motor cycle coming quickly around the bend on the incorrect side of the road. In response he panicked and swung on his steering wheel to the right, so that it went onto the incorrect side of the road. He said that the motor cyclist must have panicked and swerved the same way as well, so that the collision occurred. If she had remained where she was when he first saw her on the incorrect side, the collision would not have occurred, he said. He described the motor cycle as clipping the left side of his car.

5 The Crown's case was that his version of the events should not be accepted. This was because limited visibility around the bend meant that it was not possible that he could have seen the motor cycle in sufficient time to have reacted, lost control, left the marks on the road caused by his vehicle in a yaw and arrived at the point of impact on his incorrect side of the road at the same time as the motor cycle reached that point.

6 There was no evidence that his vehicle left the sealed portion of the road prior to going into a yaw. The factual issue between the parties was whether the yaw was caused by excessive speed on his part, as claimed by the Crown, or by him suddenly swerving to the right, as claimed by him.

7 The Crown relied on circumstantial evidence. It included evidence of members of the public that they saw a car, similar to the appellant's car, travelling at a fast speed along the route driven by the appellant shortly before the time of the accident. It also included evidence of an accident investigator, First Class Constable Lloyd. He described the scene and marks and debris on the road following the collision and, based on what he saw, gave evidence of his opinion that the appellant lost control and his car went into a yaw because of excessive speed and not because of the deliberate swerving of the car described by the appellant.

8 Ground 1(g) of the appeal attacks the admission of the evidence of the members of the public, and grounds 1(a) - (f) attack the admission of the evidence of First Class Constable Adam Lloyd.

The challenged evidence of the members of the public

9 The time of the accident was about 12.20pm, according to John Lamprey who lived 110 metres away. The evidence of First Class Constable Wotherspoon supported that. He said that the police's Command and Control System, the computer-based system for despatching units and managing incidents from the radio room, recorded that at 12.22pm a police radio room operator commenced to record that a triple 0 telephone report of the accident had been received.

10 The members of the public whose evidence is challenged on the appeal are Trevor King, his wife Christine King, Mark Tosi and Robert Taylor.

11 Mr King gave evidence that he was driving a car southwards on Natone Road with his wife as passenger. It was midday or shortly after when he met a red Falcon travelling northwards on a straight that was about 800 metres long. He passed the Falcon at a point that was about 50 metres north of a turnoff to South Riana which, according to the evidence of First Class Constable Wotherspoon, was 12.6 kilometres south of the accident scene. Mr King said that he was about 200 metres along the straight when he first noticed the Falcon. It was travelling "at quite a considerable speed ... at least a hundred kilometres an hour". The speed limit for the area was 80 kph. Because of its apparent speed, he made sure he gave it plenty of room to go past. Mr King was travelling at about 70 to 75 kph. He observed that the driver of the Falcon was male, fairly tall and "looked youngish".

12 Mr King had held a driver's licence for about 43 years and often drove on rural roads. In cross-examination he agreed that he only observed the car for a few seconds and that it is difficult to estimate the speed of other vehicles.

13 Mrs King gave evidence of being a passenger in her husband's car at the same place. She said that the approaching car was a red Falcon or Commodore. Her vehicle was travelling at between 70 and 80 kph and she estimated that the red car was travelling at more than 100 kph. She described the driver as male, sitting very upright in his seat, with short hair and looking neat, with no whiskers. He was a young person, she would say between 23 and 27. She estimated the length of the straight upon which they met the other car as being half a mile.

14 Mrs King said that she had been driving for 30 years and often drove on rural roads. She and her husband lived in a small country town, Ridgley.

15 Mark Tosi lived at South Riana. He said that at about quarter past 12, he was driving a car south on Natone Road, just south of the Natone Football Club, which was a little over 5.4 kilometres south of the accident scene. A speed limit of 80 kph applied. The traffic was light. Mr Tosi said that he was travelling at 70 kph when, probably 200 metres away, he saw approaching him a red Ford Falcon, either a 1995 or 1996 model. He estimated its speed as at least double the speed of his own vehicle. The driver was a male, probably younger than 30 and with short hair. Mr Tosi described the road as very undulating, with several dips and crests, a standard country road. The section where he saw the Falcon was a straight probably, 1½ kilometres long.

16 Mr Tosi had been employed as a bus driver for 4½ years. He had lived at South Riana for the same time and had driven along that road daily. He had travelled at a speed of 140 kph. In fact the fastest he had travelled was 240 kph on a Queensland raceway.

17 Mr Taylor's evidence was that he was sitting at his dining room table from about 10 or 5 to 12. He lived about 2.5 kilometres south of the accident scene. The speed limit at that point was 100 kph and it did not change before the accident scene. It was between 12.15 and 12.20pm when his attention was drawn "to a sound of a car travelling very, very fast" in a northerly direction along Natone Road. It was the only vehicle he had seen since sitting where he was. From there to the road was approximately 50 metres. He saw the vehicle for a second or a second and a half between trees. He said it was going so fast he could not identify its type or colour. The sound of the car backed off slightly as it approached a right hand corner in front of his house. He then heard a thump and after that the car accelerated rapidly away. His evidence did not explain what caused the thump.

18 Mention should be made of the evidence of Jurgen Milesi, although its admissibility is not challenged by the appeal. His house was on Natone Road only 380 metres south of the accident scene. He said he was working outside his house all morning. Very few vehicles were on the road that day, probably only one an hour. I note that it was the morning of Good Friday. His evidence was that probably a bit after midday he saw and heard a car go past in a northerly direction at a fast speed, following which he heard "a big bang". He looked and saw the appellant's vehicle stationary at the scene of the accident, but within about half a minute the vehicle had left the scene.

19 The evidence of the challenged witnesses was heard on the voir dire. The learned judge ruled that it was admissible, after excluding some parts. I need not deal with those parts, for the question is whether the evidence given to the jury should not have been admitted.

20 The evidence strongly gave rise to an inference that the vehicle observed by the witnesses was the one driven by the appellant. His counsel conceded that the evidence was relevant and that it had probative value. However, he argued that the probative value was very low and that the learned judge should have rejected all of it because its probative value was outweighed by the danger of unfair prejudice to the appellant. If that was so, the Evidence Act 2001, s137, required the learned judge to refuse to admit it.

21 It was submitted for the appellant that the evidence of each of Mr and Mrs King's observations had low probative value because they were of a vehicle over 12 kilometres from the scene of the accident travelling along a straight section of road. The accident occurred on a section that had bends. It was submitted that the evidence of Mr Tosi also had low probative value because his observations were of a vehicle approaching along a straight over five kilometres from the accident scene. It was submitted that Mr Taylor's evidence had low probative value because his assessment of the speed of the passing car as very, very fast was based predominantly on the sound it made.

22 Counsel for the appellant isolated the evidence of each of those witnesses when making his submissions. The argument overlooked the fact that the Crown relied on the combined effect of the evidence of Mr and Mrs King, Mr Tosi, Mr Taylor and Mr Milesi as tending to prove a course of high speed driving by the appellant over a distance of about 12 kilometres leading to the accident. The effect of all of that evidence made it more likely that he lost control on the final corner because of excessive speed and not for the reason he gave the police. When considered as a body of evidence, its probative value was not low.

23 It was difficult to understand from counsel for the appellant what he asserted was the danger of unfair prejudice from the evidence. His argument seemed to be based on the proposition that if the evidence had low probative value, and if the jury made use of it against the interests of the appellant, an error would have been occasioned and the appellant would have been unfairly prejudiced. That mis-states the concept of the danger of unfair prejudice in the Evidence Act. Evidence is not unfairly prejudicial merely because it makes it more likely that the accused person will be convicted. The danger of unfair prejudice arises if there is a real risk that the evidence will be misused by the jury in some unfair way. In Festa v R [2001] HCA 72; (2001) 208 CLR 593 at par[51], McHugh J explained:

"But the weakness of relevant evidence is not a ground for its exclusion. It is only when the probative value of evidence is outweighed by its prejudicial effect that the Crown can be deprived of the use of relevant but weak evidence. And evidence is not prejudicial merely because it strengthens the prosecution case. It is prejudicial only when the jury are likely to give the evidence more weight than it deserves or when the nature or content of the evidence may inflame the jury or divert the jurors from their task."

24 The concept was also explained by the Australian Law Reform Commission, Evidence Report No 26 (Interim) 1985 vol 1, par[644]:

"By risk of unfair prejudice is meant the danger that the fact-finder may use the evidence to make a decision on an improper, perhaps emotional, basis, ie on a basis logically unconnected with the issues in the case. Thus evidence that appeals to the fact-finder's sympathies, arouses a sense of horror, provokes an instinct to punish, or triggers other mainsprings of human action may cause the fact-finder to base his decision on something other than the established propositions in the case. Similarly, on hearing the evidence the fact-finder may be satisfied with a lower degree of probability than would otherwise be required."

25 The assessment of the evidence of the witnesses, and its collective probative value, was for the jury to determine. There was nothing about it that raised a danger of unfair prejudice.

The challenged evidence of First Class Constable Lloyd

26 Particulars (a) to (f) of the first ground of appeal assert that the learned trial judge erred in law by admitting evidence from the officer of the following matters:

(a) His opinion as to the mechanisms of the collision when he was not qualified to do so and his evidence was not based on scientific fact.

(b) Photographs of a reconstruction of how, in the opinion of First Class Constable Lloyd, the accident occurred, when there was no scientific foundation for the reconstruction.

(c) The point of impact, when it was not based on any scientific analysis, assessment or fact.

(d) The photographs of a reconstruction of how the accident occurred in the opinion of First Class Constable Lloyd, when the probative value of the evidence was outweighed by its prejudicial effect.

(e) Photographs representing a reaction time analysis made by First Class Constable Lloyd that was based on errors of calculation and an assessment of the point of impact without scientific foundation.

(f) The photographs of the reaction time analysis of First Class Constable Lloyd when its probative value was outweighed by its prejudicial effect.

27 First Class Constable Lloyd gave evidence at the trial of his opinion about a number of matters based upon his examination of marks and debris at the scene of the accident and the damage caused to the car and the motor cycle. His opinions included the point of impact; that tyre marks on the road were caused by the appellant's car proceeding in a sideways slide or yaw and demonstrated that in the course of doing so, it moved from its correct to its incorrect side of the road; and that the motor cycle was on its correct side of the road at the moment of impact. He also gave opinion evidence that led to a conclusion that the appellant's explanation to the police concerning why the accident occurred was not feasible, relying principally on the marks and debris, the damage to the two vehicles, visibility around the corner and the time that the two drivers might have taken to react to their observations of what was taking place ahead of them. In the course of giving his evidence, First Class Constable Lloyd was permitted to give evidence of reconstructions of what might have happened, his evidence being aided by the tendering of photographs showing his reconstructions.

28 The defence objected to some of First Class Constable Lloyd's opinion evidence upon the basis that under the Evidence Act, s79, he did not have specialised knowledge, based on his training, study or experience, upon which his opinions were wholly or substantially based. In other words, his qualifications as an expert were attacked. The objection was also based on a claim that in coming to his opinions the methodology he used was faulty and had no, or insufficient, scientific basis.

29 First Class Constable Lloyd gave evidence on the voir dire. Following submissions, the learned judge permitted him to give the evidence before the jury of his opinions that included those challenged by particulars (a) to (f) of the first ground of appeal.

30 First Class Constable Lloyd gave evidence that he had been a police officer since 1994. For approximately 10 years of that he worked in Western Traffic Services, and for approximately eight years of that time he was either working in accident investigation or relieving as needed in that area. He had attended hundreds of motor vehicle accident scenes. Initially he received four years of mentor training from a senior constable who was in charge of accident investigation. The training was on the job by attending crash scenes and being shown how to mark scenes, gather evidence and obtain witness statements. First Class Constable Lloyd said that in 2008 he completed a correspondence course run by the University of North Florida's Institute of Police Technology and Management. The course covered a basic understanding of vehicles; road markings; different marks made by vehicles when crashes occur; and basic speed analysis from yaw marks and skid marks. The correspondence course took him four or five months. Modules were sent to him in the mail. The University of North Florida's Institute of Police Technology and Management is one of the few places offering training throughout Australia and the only one used by Tasmania Police.

31 In October 2008, First Class Constable Lloyd completed a course at the Police Academy in Hobart that was conducted by the Australian Director of the University of North Florida's Institute of Police Technology and Management. It was a comprehensive two week course that included theory and practice with competency-based assessments on the use of formulae and investigative principles for motor vehicle crash reconstruction analysis. The correspondence course he had completed earlier provided a basic understanding of collision investigation principles. The October 2008 course gave instruction at an advanced level in crash analysis. It looked at things such as momentum analysis and vector analysis to obtain speeds using mass, kilojoules and the like.

32 First Class Constable Lloyd said that he had kept up- to-date by reading literature concerning accident investigation. Most of it was to be found on-line. He had also had on the job training concerning how to use a Geodimeter, which is used at an accident scene for the purpose of producing a computer-based scale plan.

33 Counsel for the appellant made some point of the fact that at the time of the accident in March 2008, First Class Constable Lloyd had received some of his training but had not attended the two week course conducted the following October. In cross-examination he agreed that at the time of the accident he was qualified to do yaw analysis but not to do momentum analysis. He seemed to accept that at the time of the accident he was not qualified to carry out a full reconstruction of an accident from an accident scene using variables such as a vehicle's weight, mass and velocity. However, he emphasised that he did not carry out a reconstruction of the accident in that sense. I add that his qualifications at the time of giving evidence were what counted most for the admissibility of his opinions.

34 First Class Constable Lloyd attended the scene of the accident shortly after it happened. He observed the position of the body of the deceased and the motor cycle, debris, gouge marks and tyre marks. He determined what he referred to as the extremities of the scene. He directed that photographs be taken of the scene by forensic officers. He and another officer then marked pertinent points with paint, and more photographs were taken. The photographs were in evidence at the trial.

35 He gave evidence of two yaw marks visible on the bitumen road surface that were caused by tyres of a motor vehicle. He said his training enabled him to say they were yaw marks, that is to say, they were marks caused by tyres under rotation sliding sideways. They were not skid marks left by a vehicle under brakes. The difference between the two is that a rotating tyre slipping sideways leaves a mark with striations through it, whereas a braking tyre mark has no striations. The two marks he observed had striations. His qualifications to give evidence of his opinion that they were yaw marks and not skid marks are not attacked by the appeal. The appellant's counsel conceded to the learned trial judge that the officer was "qualified to do a yaw analysis and he was also qualified to do a reaction time analysis" and "could do the yaw analysis and give his opinion about speed".

36 It was the opinion of First Class Constable Lloyd that the two visible yaw marks were caused by the appellant's car. Assuming that they were caused by a car travelling from south to north, the longest, which was 28 metres in length, commenced just on the appellant's correct side of the double white lines marking the centre of the road, and then crossed the centre lines, curving slightly to the right, and continued on the incorrect side of the road, terminating at a point which, in the opinion of First Class Constable Lloyd, was the point of impact. (I will deal with that aspect of his opinion in due course.) It was also his opinion that the longer of the two visible yaw marks was caused by the front passenger side tyre of the car. There was also a much shorter yaw mark, to the west of the longer mark, which First Class Constable Lloyd attributed to the rear passenger side tyre. It also curved slightly to the right, crossed the centre lines and stopped near to his designated point of impact. That it was outside or to the west of the mark from the left front passenger tyre demonstrated that the vehicle was rotating clockwise and in a sideways slide to its left. First Class Constable Lloyd explained that with the vehicle sliding to its left, only the tyres on the left side of the vehicle left marks on the road surface. It was to be expected that the left front tyre would leave a longer yaw mark than the left rear tyre because more of the vehicle's weight would have been transferred onto the front tyre.

37 The opinions of First Class Constable Lloyd concerning the yaw marks and which tyres caused them are not attacked by the appellant.

38 An opinion was also expressed by First Class Constable Lloyd that the vehicle's yaw would have commenced at a point earlier than when the first visible marks of the yaw appeared on the road surface. By extending the arced lines of each of the yaw marks to the south until they coincided, a computer program determined that point to be about 37 metres south of the commencement of the southern most visible yaw mark, which was the longer of the two. However, he accepted that such a calculation was not "exact science". Because all of the marks he saw had striations, it was plain that the yaw had commenced earlier because it can be expected that the start of a yaw mark will consist of a single black line until eventually, striations commence to appear. However in this case, he was unable to see marks any earlier than he did. He explained that as the longer of the two visible marks, that is the one from the left front tyre, commenced close to the double white centre lines (a distance he said was .49 metres), three quarters of the vehicle must have been on the incorrect side of the road at that time as it continued to rotate clockwise and, consistent with the yaw marks, gradually curved further onto the incorrect side of the road.

39 First Class Constable Lloyd's evidence was that there had to have been a momentum change in order for the car to have commenced to yaw where it did. Something caused the vehicle to change momentum and the appellant to lose control of it. One possibility was that he was travelling too fast to be able to maintain control through the bend, so that through excessive speed on the bend the vehicle commenced to yaw. Another possibility was that the appellant swung the steering wheel to the right in an attempt to avoid colliding with something, so that the vehicle commenced to yaw. No other possibility was advanced at the trial.

40 He said that it could be expected that if excessive speed was the cause of the vehicle commencing to yaw the curvature of the yaw would be a gradual one, the vehicle "slowly moving to a point where it's sideways". However, if the driver swerved to avoid something, he would expect to see "a much harsher arc from the yaw mark", the yaw would be "a lot more severe" and the move to the opposite side of the road would cause far darker marks in a tighter arc than those left by a yaw with a gradual arc brought about by excessive speed. In this case, his opinion was that the yaw marks were in a gradual arc rather than a tight arc.

41 First Class Constable Lloyd expressed his opinion, based on measurements and calculations, that the average minimum speed of the vehicle across the yaw was 78 kph. His qualifications to express that opinion were not the subject of challenge at the trial. My understanding is that he made the calculation in accordance with an accepted formula that is contained in a formula book produced by the University of Florida's Institute of Police Technology and Management, after determining the coefficient of friction between the road surface and the car's tyres by dragging a tyre filled with concrete weighing 12.5 kilograms along the yaw mark; measuring the length of the chord of the arc left by the first 10 metres of the yaw mark; and measuring the length of the perpendicular bisector of that chord from the chord to the yaw mark.

42 Within no more than a metre off the inside edge of the bitumen surface on the right hand bend, and only a few metres north of First Class Constable Lloyd's assumed point of impact, was a steeply elevated and grassy bank. It restricted visibility around the bend. On the bank was an impression through the grass, consistent with having been caused by a tyre of a vehicle running off the side of the bitumen from the south, across and up the bank and then curving slightly to the left, as if the vehicle was on the way to returning to the road surface. It was the opinion of First Class Constable Lloyd that it was caused by the driver's side front tyre of the appellant's car. Having regard to the positions of the yaw marks, it appeared unlikely to have been caused by one of the passenger side tyres. The officer's opinion was consistent with what the appellant said in his interview, that after the collision his car ran up the bank.

43 I deal next with First Class Constable Lloyd's opinion concerning the point of impact. He said it was .48 metres on the eastern side of the centre line on the road, that is on the appellant's incorrect side of it, and 28 metres north of the commencement of the longer of the two yaw marks. He formed that opinion when he examined the scene and continued to hold it after completing the October 2008 course. His opinion was based on the fact that the yaw marks led up to that point and ended there; there were two gouge marks in the road surface that were close to each other at that point, the cause of which he attributed to a foot pedal of the motor cycle, which was lying a few centimetres away, and some other part of the motor cycle's frame; there were no other marks, such as gouge marks, consistent with an alternate point of impact; the position of the motor cyclist on the road, and of the motor cycle, after the collision at points much further north, demonstrated that they were carried, dragged or thrown by the car in a northerly direction; and drag marks on the road surface to the north of the assumed point of impact were consistent with the motor cycle being dragged by the car. His opinion was supported by the tyre mark on the grassy bank which the appellant said his car had run up after the collision. Its position suggested that the vehicle that caused it had come from the assumed point of impact, or thereabouts. The assumed point of impact was also supported by the fact that there was very little debris south of the two gouge marks, but a great deal of it to the north, along with other gouge and scuff marks leading to the final resting places of the motor cycle and its rider. That the point of impact was on the appellant's incorrect side of the road was accepted by him when he was interviewed by police.

44 First Class Constable Lloyd explained when giving his evidence on the voir dire, that when two vehicles travelling in opposite directions collide, a downward force is occasioned tending to force the vehicles down and cause gouge marks. That was part of basic training for accident investigation and enabled the determination of the point of impact.

45 Before the jury he gave similar evidence. No evidence contradicted it. He said that upon impact between the motor cycle and the car, the front wheel of the motor cycle bent, and the motor cycle moved forwards and downwards, and at that point the foot peg went into the road surface and broke off.

46 When giving evidence on the voir dire, First Class Constable Lloyd did not say which of the motor cycle's two foot pegs had broken off, but in cross-examination before the jury he said it was the one on the right side of the motor cycle. However, photographs of the damaged motor cycle showed that it was the left foot peg that had broken off and was lying on the road near the two gouge marks. When shown a photograph establishing that, he apologised to counsel and said he had made an error.

47 Counsel for the appellant argued that the error weakened the probative value of First Class Constable Lloyd's evidence concerning the point of impact. However, there was no evidence to suggest that whether the foot peg came from the right or left side of the motor cycle affected the witness's opinion concerning the point of impact. For that reason, the error may safely be disregarded.

48 There were no gouge marks further south than the assumed point of impact, although there was a small amount of motor cycle debris there. At the trial, when addressing the learned judge concerning the admissibility of the evidence, counsel for the appellant referred to it as "some minor debris". Some of it was west of the centreline. First Class Constable Lloyd's opinion was that it was thrown there following the impact. There was far more debris north of the assumed point of impact, most of it on the eastern half of the road. It was argued by counsel for the appellant that the fact that there was some debris south and west of the assumed point of impact threw doubt on the officer's opinion and raised the possibility that the point of impact may have been further to the south and on the appellant's correct half of the road. However, the concession of the appellant to the police that the collision occurred when he was a "fair bit" on his incorrect side of the road, the relatively small amount of debris to the south, and the lack of gouge marks to the south, made that an unlikely possibility.

49 Following the hearing of First Class Constable Lloyd's evidence on the voir dire, counsel for the appellant submitted to the learned trial judge that the officer had not given any scientific basis for his opinion about the point of impact. Counsel submitted that it amounted to no more than an assumption by the witness. He submitted further that because the witness gave no scientific basis for his opinion, he was not qualified to give the evidence (as an expert), and the probative value of his opinion was outweighed by the danger of unfair prejudice to the appellant if the evidence was permitted. Ground 1(c) of the appeal also raises the claim that there was no scientific basis for the opinion.

50 The learned trial judge admitted the evidence of the opinion concerning the point of impact. His Honour referred to the requirement of the Evidence Act, s79, that the witness's opinion be wholly or substantially based on specialised knowledge that is in turn based on the witness's training, study or experience. I observe that a scientific basis for the opinion, which was the argument of the appellant's counsel before this Court and the court below, is not a requirement of the section.

51 The learned judge found that First Class Constable Lloyd had specialised knowledge based on training, study and experience, but recognised the need to confine his opinion evidence to matters within his reasonable expertise. See R v Murphy [1980] QB 434 at 437, referring to R v Oakley [1979] RTR 417 at 421. In R v Bjordal [2005] SASC 422; (2005) 93 SASR 237 at 245, Debelle J summarised the accepted authority of Makita (Aust) Pty Ltd v Sprowles [2001] NSWCA 305; (2001) 52 NSWLR 705 at par[85] as including that the opinion must be based on the expert knowledge of the witness. Another way of expressing the point is that it concerns whether the witness has acquired by training, study or experience sufficient knowledge of the subject to render his or her opinion of value in resolving the issues before the court. R v Bonython (1984) 38 SASR 45 at 47; Clark v Ryan [1960] HCA 42; (1960) 103 CLR 486 at 491 - 492.

52 The learned judge was satisfied that the witness was qualified to give evidence of his observations at the scene and his opinions based thereon, including his opinion concerning the point of impact. His Honour's finding was consistent with the evidence and a correct one. First Class Constable Lloyd was a trained and experienced observer of motor vehicle accident scenes. Without his observations, and his opinions based on them, the jury would have had considerable difficulty forming a sound judgment on what the evidence at the scene of the accident tended to establish. The witness's evidence concerning the point of impact was typical of evidence regularly given by trained accident investigators in like cases.

53 The learned judge has not been shown to have erred in admitting the evidence concerning the point of impact. First Class Constable Lloyd's evidence established that it was based on his knowledge, training and experience as an accident investigator and his observations at the scene.

54 Before dealing with First Class Constable Lloyd's evidence of reconstruction of what might have occurred to cause the accident, it is appropriate to explain in more detail the explanation for the accident that was given by the appellant to the police later the same afternoon. He said that he was travelling at 70 - 80 kph. Later he said "75 if that". As he went to go around the right hand bend, which he described as sharp, he saw the motor cycle "coming flying round the corner" on its incorrect side of the road. As a result, he panicked and swerved onto his incorrect side of the road to avoid the motor cycle. He said that the motor cyclist must have panicked and swerved as well, and the collision occurred "a fair bit" onto the appellant's wrong side of the road. The interviewing officer put to him that he had lost control and his vehicle had gone into "a sideways yaw". The appellant accepted that but said it only happened when, faced with the motor cycle on his side of the road, he panicked and swerved to the right to avoid a head-on collision. He had no idea of the speed of the motor cycle, except that it was "moving pretty quick ... way too quick to be on his [sic] right side of the road ... God he [sic] was moving".

55 First Class Constable Lloyd gave evidence that on 4 April 2008 he returned to the scene of the accident with other officers, a Ford Falcon sedan that was virtually identical to the appellant's car, and a motor cycle that was virtually identical to the deceased's motor cycle. He then carried out a number of reconstructions of what might have occurred at the time of the accident, using the two vehicles in conjunction with his observations of the scene of the accident. He had photographs taken to record the reconstructions. They were also in evidence before the jury.

56 For example, he had the exemplar car placed on the yaw marks at various points along them, so as to demonstrate what must have been the position of the appellant's car on the road surface when its tyres were making the marks. The exemplar car's front passenger side wheel was placed at various points along the longer of the two yaw marks, and the rear passenger side wheel on the shorter of those marks. If his opinion as to which of the tyres caused the respective yaw marks was correct (his evidence about that is not attacked by the appeal), then there is only one position in which the appellant's car could have been at any one point when both of the yaw marks appeared on the road surface. Thus, a number of photographs of the exemplar car showed where the appellant's car must have been, if the marks were in fact caused by those two tyres. Among other things, these photographs demonstrated that at the northern end of the yaw marks, which coincided with the point of impact according to First Class Constable Lloyd's opinion, the appellant's car completely blocked the eastern half of the bitumen road surface, as well as part of the western half.

57 A number of the photographs taken of the reconstruction exercise showed the position of the appellant's car at the point of impact if the officer's opinions as to the position of the point of impact and the position of the appellant's car on the yaw marks were correct. Those photographs also showed the exemplar motor cycle positioned by the officer on the road surface where be believed it hit the side of the appellant's car. However, while First Class Constable Lloyd was firm in his opinion that the car could only have been in one position at any one point along the two visible yaw marks, and at the point of impact, he accepted that the angle of the motor cycle to the side of the car, as shown in the photographs, was not necessarily correct.

58 One of the purposes of another aspect of the reconstruction was to determine whether the accident could have occurred in the way the appellant explained to the police. An effect of it was that because of limited visibility around the corner, it was impossible, in the time and distance available, that the appellant could have seen the approaching motor cycle, reacted to an observation that it was on its incorrect side of the road, swung the steering wheel to the right, following which the car produced the two yaw marks until at their end, or thereabouts, the motor cycle collided with the car. Another effect of it was that having regard to the limited visibility, it was impossible for the motor cyclist to have travelled on the incorrect side of the road, observed the approaching car, reacted to what she saw, and returned to her correct side of the road where the collision occurred.

59 However, First Class Constable Lloyd did not give evidence that they were the effects of his reconstruction. That was left for argument by counsel to the jury and comments from the trial judge in his summing-up. I will explain with examples some of the evidence of the officer's reconstructions.

60 He gave evidence that it was accepted that the average person, unaffected by alcohol or drugs, takes 1.5 to 1.6 seconds to react to what is perceived. Using 1.6 seconds as the relevant reaction time, he positioned the exemplar car on the western half of the bitumen road at a point that was 36 metres south of the commencement of the longer of the two yaw marks. The appellant had told the police that his speed was 70 to 80 kph. A driver travelling at 80 kph, who takes 1.6 seconds to react, would travel 36 metres before commencing to react. It followed that if the appellant was driving at 80 kph and he took the average 1.6 seconds to react, he would have been at least 36 metres south of the commencement of the longer yaw mark and 64 metres from First Class Constable Lloyd's assumed point of impact, when he first saw the motor cycle on its incorrect side of the road. Using the line of sight across the bend from that point, the officer positioned the exemplar motor cycle on the western edge of the road at a point where the driver of the exemplar car could first have seen the motor cyclist's helmet approaching around the corner. He had photographs taken of them in those positions. By taking measurements, he determined that the two vehicles were 74.1 metres apart, and that the motor cycle would have been only about 10 metres north of the assumed point of impact.

61 He gave evidence that if the calculations were based on a reaction time of 1.5 seconds rather than 1.6 seconds, the measurements to which I have referred would be slightly different. In accordance with his evidence, the motor cycle would have been about 13.8 metres north of the assumed point of impact and the car would have been about 61.8 metres south of it, at the earliest point in time when the two drivers could have seen each other for the first time.

62 On the basis of those figures, the reconstruction evidence suggested that the motor cycle could not have been "flying", which is what the appellant claimed to police. Instead it would have had to be proceeding at a very slow speed to reach the point of impact at the same time as the appellant's car.

63 Arguably, and rather convincingly, the reconstruction evidence was more favourable to the appellant than it needed to be. I referred earlier to the evidence of First Class Constable Lloyd that the car commenced to yaw about 37 metres south of the commencement of the southern most visible yaw mark, which was the longer and most visible of the two. If that was so, then applying an average reaction time of 1.5 or 1.6 seconds, the motor cycle would have passed the assumed point of impact, that is, it would have been south of it, at the time when the appellant, on his version of the events, saw the motor cycle for the first time and commenced to react to what he saw.

64 First Class Constable Lloyd performed another similar reconstruction exercise that was based on an assumption that the car was travelling at 70 kph rather than 80 kph.

65 It is unnecessary to refer to all of the evidence of reconstructions. It included photographs taken of the exemplar vehicles at various positions at the scene when the reconstructions were being carried out. In summary, it was damaging to the defence case that relied on the appellant's version of the accident in his interview. The evidence tended to disprove the defence claim that he lost control on the corner because he swerved to avoid a collision with the motor cycle, and to support the Crown's case that he lost control because of excessive speed.

66 At the trial, the appellant challenged the accuracy of the assessment of First Class Constable Lloyd of the point of impact. It was his case that the point of impact was a critical issue and that the jury should not accept the officer's opinion about it. He argued that the point of impact could not be determined. It was also argued to the jury by defence that all that could be said from the photographs of the damaged motor cycle was that the front forks were bent backwards on impact, and not that the motor cycle had been forced downwards so that it caused the two gouge marks in the road surface. It was argued that the point of impact may have been somewhere other than where First Class Constable Lloyd thought it was. Reference was made to marks and debris on the road over an extended area. It was claimed that there were inadequate explanations as to how they came to be there.

67 However, apart from pointing to a few mistakes that First Class Constable Lloyd made in the course of giving his evidence, it was not argued to the jury that his evidence of reconstruction was erroneous for any reason other than his location of the point of impact.

68 The appellant objected to the reconstruction evidence at the trial, and at the hearing of the appeal his counsel argued that none of it should have been admitted. In particular, it was argued that the admission of the photographs that would have assisted the jury to better understand the reconstructions performed by First Class Constable Lloyd gave rise to a danger of unfair prejudice to the appellant because there was a real risk that the jury would treat the photographs as "hard evidence" and give the evidence of First Class Constable Lloyd's reconstructions, including his opinions upon which they were based, greater probative value than they deserved.

69 It was also argued that the learned judge erred by admitting the reconstruction evidence because it was essentially calculations based on opinions concerning the point of impact, and his qualifications to give that evidence under s79 were not established. I rejected that argument earlier in these reasons.

70 It was argued further that as the reconstruction evidence was substantially based on a theoretical reaction time, and not on the appellant's actual reaction time, the evidence should not have been admitted. For example, it was pointed out that if the appellant had reacted within one second, rather than within 1.6 seconds, the damaging effect of the evidence would have been reduced. It followed, it was submitted, that the probative value of the reconstruction evidence of First Class Constable Lloyd was very low. It was argued that the danger of unfair prejudice was correspondingly high.

71 I reject those arguments. The training, study and experience of the officer enabled him to give evidence of average reaction times. He conceded that the reaction time of the appellant may well have been more or less. His evidence of the line of sight around the corner, and the distance at which the appellant could first have seen the motor cycle on the incorrect side of the road, were based on measurements taken at the scene. That aspect of his evidence was based on fact and not opinion. That also applies to his evidence of other measurements and distances. His evidence of distances travelled at certain speeds, in certain times, was factual in that it was based on mathematical calculations.

72 In cross-examining the witness, counsel for the appellant could have asked him to make other calculations based on different speeds for the car and different reaction times for its driver. It was also open to the appellant's counsel to provide mathematical calculations concerning speed, time and distance in his closing address to the jury. He could have invited the jury to make its own calculations.

73 There was nothing unfairly prejudicial in the reconstruction evidence. Largely, it was uncontroversial, except as to the point of impact. The photographs that complemented it would have enabled the jury to better understand it, but there was not a realistic risk that the jury would have misused the photographs, or the reconstruction evidence, in some improper way.

74 The evidence was directly relevant to the issues that were raised between the parties. Questions of fact were raised by them and, quite properly, the jury were allowed to consider the evidence and make their own findings of fact concerning the feasibility of the appellant's explanation for the accident.

75 For these reasons, ground 1(a) - (f) have not been substantiated.

76 Paragraph (a) of ground 2 asserts that the verdict was unsafe and unsatisfactory because the jury "could not be satisfied beyond reasonable doubt as to the guilt of the accused as no evidence was adduced as to the critical speed of the corner where the accident occurred which is the paramount issue in determining if the accused was guilty of culpable negligence". Paragraph (b) asserts that the verdict was unsafe and unsatisfactory because the jury "could not be satisfied beyond reasonable doubt as to the guilt of the accused on the case [sic] being circumstantial, could not have excluded every hypothesis consistent with the accused [sic] innocence".

77 The reference to the critical speed of the corner was to the maximum speed at which the appellant's car could have rounded the corner without loss of control, and above which the vehicle was liable to commence to yaw. There was no evidence at the trial of what it was, nor was there evidence concerning whether it was capable of being determined. However, there was evidence from First Class Constable Lloyd that a speed that is excessive for a corner can cause a driver to lose control and a vehicle to yaw; that the yaw marks were more consistent with having been made by a car in a yaw because of excessive speed, and less likely to have been caused by a car in which the driver wrenched on the steering wheel; and that the vehicle may have commenced to yaw before it entered the corner on which the accident took place.

78 In deciding whether the verdict should be set aside as unsafe and unsatisfactory, the question for the Court to determine is whether the jury, acting reasonably, must have entertained a reasonable doubt as to the guilt of the appellant. It is for the Court to decide whether, on the relevant evidence, it was open to the jury to be satisfied beyond reasonable doubt of his guilt. In deciding these questions, it is the duty of the Court to make an independent assessment of the evidence. In making that assessment, the Court must necessarily take into account the nature and quality of the evidence. As to all of those propositions see Chidiac v R [1991] HCA 4; (1991) 171 CLR 432 at 442 - 443 and the cases cited therein.

79 However, it is not the function of the Court to substitute itself for the jury and re-try the case, nor is it for the Court to decide whether the verdict is against the weight of the evidence. Rather, it is for the Court to determine whether there is a significant possibility that an innocent person has been convicted because the evidence did not establish guilt beyond reasonable doubt. Chamberlain v R (No 2) [1984] HCA 7; (1984) 153 CLR 521 at 618 - 619; Chidiac v R at 443 - 444.

80 There was a body of compelling evidence that the appellant's loss of control and the vehicle's movement onto the eastern half of the road were caused by excessive speed and were not in accordance with his explanation to the police. I refer to the following:

1 The evidence of Mr and Mrs King, Mr Tosi, Mr Taylor and Mr Milesi, in combination, was capable of establishing a course of high speed driving by the appellant over a distance of about 12 kilometres leading to the accident.

2 The evidence of police officers of their observations at the scene of accident and in particular, the evidence of First Class Constable Lloyd, and his opinions based on his knowledge from his training, study and experience as an accident investigator, was capable of establishing that the point of impact was where he said it was on the appellant's incorrect side of the road. That was consistent with the two yaw marks leading up to that point where they ended, the two gouge marks that were close to each other at that point, the lack of other gouge marks in the near vicinity consistent with a different point of impact, the tyre mark on the grassy bank that was consistent with it having been made by the appellant's car after a collision near there, and the appellant's version of the accident to the police.

3 The opinion of First Class Constable Lloyd that the yaw marks were more consistent with being caused by a car that was out of control through excessive speed and was less likely to have been caused by a car as a result of the steering wheel having been wrenched to the right.

4 The evidence of First Class Constable Lloyd of the line of sight around the corner, which in conjunction with his opinions concerning the point of impact, the point at which the vehicle commenced to yaw, and average reaction times, suggested that the appellant's version of the accident was highly unlikely to be true.

5 The evidence of Mr John Lamprey, who was in his home 120 metres from the accident scene, that after hearing the sound of "an explosion", which could only have been the sound of the collision, he heard the sound of scraping, which he attributed to "scraping down the road, like plastic on metal and metal on metal". That was consistent with the evidence of First Class Constable Lloyd's opinion that following the impact, the motor cycle was, for a time, embedded in the left passenger door of the car and dragged a distance north of the point of impact along the road until it disengaged from the car and slid further north to its final resting place.

6 The evidence that the appellant drove away from the scene within a few seconds of the occurrence of the accident, without attempting to render or obtain assistance for the deceased. His explanation to the police for doing so was that there were no houses. The undisputed evidence was that there were at least two houses in the immediate vicinity of the accident scene and that he drove past 33 houses to the north that were immediately alongside the road, and passed a telephone box at Stowport, before he stopped to speak to the driver of a vehicle travelling in the opposite direction, told the driver there had been an accident, and asked him to call emergency. The evidence was capable of supporting a conclusion that he drove away from the scene of the accident out of a consciousness of guilt concerning its cause.

81 I conclude that the verdict of guilty was justified by the evidence and that there is not a significant possibility that the evidence did not establish guilt beyond reasonable doubt. The jury properly concluded that a hypothesis consistent with innocence was not reasonably open. The verdict was not unsafe and unsatisfactory.

82 The fact that there was no evidence of the critical speed of the corner is not a significant factor in favour of the appellant. There was a considerable body of evidence that he was driving at speed and that it caused him to lose control.

84 For the reasons I have given, the appeal and the application for leave to appeal should be dismissed.

85 I have had the opportunity of reading the draft reasons of the Chief Justice. I agree with those reasons and would also dismiss the appeal.

86 I agree that for the reasons given by Crawford CJ, the appeal should be dismissed.