OUTER HOUSE, COURT OF SESSION
 CSOH 6A
OPINION OF LORD DOHERTY
in the cause
LEONORA McINNES as legal representative of KAYA McINNES
(First) NORWICH UNION INSURANCE LIMITED, and (Second) AXA INSURANCE UK plc trading as AXA INSURANCE
Pursuer: Comiskey; Thompsons, Solicitors
First Defender: D I Mackay QC, Murray; Simpson & Marwick, WS, Solicitors
Second Defender: I G Armstrong QC, Love; Andersons, Solicitors LLP
19 January 2012
 The pursuer is the legal representative of her daughter, Kaya McInnes. On the evening of 24 March 2007 Kaya was a rear seat passenger in a green Peugeot 306 car being driven southwards on the A9. She was aged 13. At a point in the road near Cuaich, Dalwhinnie, the Peugeot collided with a Ford Transit camper van. The camper van was being driven northwards by Richard McNicoll. It had swerved on to the southbound carriageway into the path of the Peugeot. The driver of the Peugeot and Kaya's aunt - who was a rear seat passenger - were killed. Kaya was seriously injured.
 The first defenders are the motor insurers of Mr McNicoll. The second defenders are the motor insurers of Ronald McLean, who was the driver of a Vauxhall Combo van and had overtaken Mr McNicoll's camper van and other cars immediately prior to the collision. The pursuer sued both defenders jointly and severally maintaining that the collision was caused through the fault and negligence of Mr McNicoll and Mr McLean. Each defender denied liability and contended that the accident was caused through the sole fault of the other defenders' insured. At a joint consultation between the parties on 21 October 2011 the defenders agreed that the pursuer was entitled to recover damages from one or other of them. Damages were agreed. A pre-trial meeting took place between the defenders on 25 October 2011. The Minute of the meeting records that the action in so far as it relates to the pursuer had been settled; that the agreed damages had been paid to her; and that the only remaining live issue was apportionment of liability between the defenders.
 At the proof Miss Comiskey appeared for the pursuer. She sought leave to withdraw which I granted. Counsel for each of the defenders acknowledged that the pleadings were in a rather unsatisfactory form. However, neither party proposed to found on any omission in the pleadings. Each of the defenders was clear as to the case the other made. Each sought apportionment of liability.
 The witnesses led by the first defenders were Richard McNicoll, Detective Sergeant Margaret Miller, and Hugh Drummond. The second defenders led Justine Stewart, Ronald McLean and P.C. George Lemmon. There were also two Joint Minutes of Admissions. I set out below the salient parts of the evidence.
 Mr McNicoll was aged 72 at the proof. He was a retired panel beater. He spoke to driving his camper van north on the A9. He was travelling at about 50-60 m.p.h. His wife and three of his grandchildren were passengers. He was on part of the road near Cuaich where it is a single carriageway in each direction. He was in a line of traffic moving northwards. He was about 20 yards behind the silver BMW car in front of him. He was overtaken at speed by a white van (driven by Mr McLean). It cut in between his camper van and the vehicle in front. At that point there was no traffic to be seen in the southbound carriageway. Mr McNicoll had to brake gently and slow down. According to Mr McNicoll his wife had exclaimed "This guy is going to cause an accident". The stretch of road they were on bent gradually to the right. The van moved out again to overtake the BMW and a minibus in front of it. It cut in front of the minibus. The vehicles in front of him, including the BMW, braked. The BMW braked severely. The camper van had been about 20 yards behind the BMW when it braked. At the time he had thought that was a safe distance. He had not heard of the "two second rule". He had heard that stopping distance should be at least a vehicle length for each 10 m.p.h. of speed. The camper van had been travelling at about 50 m.p.h. When Mr McNicoll first saw the BMW's brake lights go on he had braked hard - but not severely. He swerved to the right in an effort to avoid the BMW. Then he braked severely. He "just touched" the BMW, breaking its offside tail light and damaging its bumper. He ended up "in the middle of the road". The southbound Peugeot collided with his camper van. He had not seen the Peugeot when he had braked. He first saw it seconds before the collision. As a result of the collision he had pled guilty at Inverness Sheriff Court to having contravened section 3 of the Road Traffic Act 1988. The terms of the charge to which he pled were:
"on 24 March 2007 on a road or other public place, namely the A9 road, approximately one mile north of Cuaich, by Dalwhinnie you .... did drive a mechanically propelled vehicle, namely motor camper van registered number WSX 7 without due care and attention or without reasonable consideration for other persons using the road or public place drove too close to a preceding motor car, registered number W237 KAB, then being driven by Margaret Thomson or Stewart, ... collided with the said motor car and said motor camper van and said motor car....were damaged, swerved onto the opposing carriageway and collided with an oncoming motor car registered number T239 KBU, then being driven by James McKinlay, now deceased, and said motor camper van and said motor car, registered number T239 KBU were damaged and said James McKinlay and Elizabeth McInnes Foley Hall, now deceased, Duncan McInnes, Margaret McInnes and Kaya McInnes ... all passengers in the said motor car, registered number T239 KBU, were injured...CONTRARY to the Road Traffic Act 1988, Section 3 as amended."
In examination-in-chief Mr McNicoll was asked "What was it about your driving that was wrong?" His answer was that there had been lack of concentration on his part. He had been distracted by the driver of the white van's "erratic" driving. He explained that "too many things were going on at once - the white van and then the braking." He had not deliberately been driving too close to the BMW: "At the time I thought it was a safe distance". In cross-examination he accepted he could have swerved to the left but that he hadn't had much time to decide which way to go. He accepted that the BMW and the minibus in front had both managed to brake without colliding with the vehicles in front of them. He agreed that had there been a greater distance between his vehicle and the BMW he would have had more time to react when the BMW braked. He agreed that in tendering his plea of guilty he had admitted that he had been driving too close to the BMW. In re-examination he deponed that camper vans take longer to stop than ordinary saloon cars: and that that would affect the stopping distance required.
 Mrs Stewart, the driver of the BMW, was medically unfit to attend the proof or to give evidence on commission. Martin Probst and Nathaly Kratzer were Swiss residents who had been in the car in front of the BMW at the time of the accident.. Each of these three witnesses had given a statement to police at the locus immediately after the accident. It was agreed that their (copy) police statements (nos. 7/4, 7/6 and 7/7 of process) were true and accurate accounts of what they had then said and that those accounts should be taken to be the equivalent of their evidence.
 Mrs Stewart was aged almost 54 at the date of the accident. Her account was that she was driving her BMW "in a convoy of cars heading north." The white camper van was behind her. She was driving at a speed of about 50 to 60 m.p.h. She became aware of a white van overtaking her. She first noticed it as it passed her driver's window. She observed:
"I cannot estimate the van's speed. It was not particularly speeding. It continued on the southbound carriageway overtaking the northbound cars. I think it overtook about three cars, me and another two cars ahead of me. As the car overtook us I saw a car travelling southbound. It immediately became obvious to me there was going to be a head on collision. The van was still on the southbound carriageway and didn't look as if it was going to get back in. I thought it was going to be a head on with the white van and the southbound car. I could see what was going to happen so I began to brake as did the other northbound cars, trying to let the white van in. I said to my daughter "Oh shit". As I braked I put my left arm in front of my daughter to protect her. As all the vehicles had braked the white van got back on to the northbound carriageway. Then, it was all so quick I never saw the southbound car pass me. I then felt something bump my car. Justine got a fright as did I, I slowed down, I wondered what happened....I thought the driver of the white van was crazy, overtaking in the face of a southbound vehicle. His overtaking was dangerous....At the time of the accident it was daylight, there was no blinding sun in eyes, visibility was good and clear. The road was dry and well maintained. It has clear road markings on it. In my opinion, the van driver's overtaking and pulling in made everyone brake and cause this accident. The manner of his driving (white van) has caused everyone else to brake and take action resulting in this road accident. I don't think anyone else's driving was at fault. There are no other facts which my (sic) be contributed to this accident."
 Mr Probst was a Ph.D. student. He was driving a Peugeot 307 car northbound. He was in front of Mrs Stewart's BMW and behind a white bus. The relevant part of his account was as follows:
"We were travelling quite slowly, but there was a lot of people overtaking. I was looking to overtake the white bus - looking for a long space. Suddenly, this white van came, I saw it in the rear mirror. I saw it overtake the BMW behind me, and I saw the green car coming in the opposite direction (south). I slowed down, to give the white van a gap to get into the front of me, between me and the bus. I probably braked. The white van managed to get in in front of the bus, but it was very tight. I looked up in the mirror and I heard bang, bang, bang. I saw the camper van hit the rear of the BMW (on the corner) and it veered off to the other side of the road. I saw the green car crash into the camper van....the overtaking was unnecessary."
 Ms Kratzer was Mr Probst's girlfriend. She described her occupation as a "PR specialist". She was the front seat passenger in the car driven by Mr Probst. The relevant part of her account stated:
"(W)e were behind a bus, a little bus, like a minibus, I think it was white, perhaps with some blue stripes on the back.... As we reached a point on the A9, about 20 minutes past Bruar, we were still behind the minibus. A silver BMW was travelling behind us. Since I was not driving I did not pay much attention to following or proceeding (sic) vehicle but I recall being behind the minibus for some time. As we travelled north a white van (a little white van) overtook about three or four cars, in one move. He overtook us, a white minibus, and a silver BMW behind us. We were travelling about 50-60 m.p.h. The white van overtook us at speed ...As it passed us I could see another vehicle, a car, travelling south. This was while the white van was still overtaking.... It was obvious to me that the white van had no time to pull back in. The southbound car was heading straight towards the white van in the southbound carriageway. I saw the white van pull in so quickly. I was still so shocked about what I had seen I never saw the southbound car pass us. I just then heard a crash .... The weather at the time of the accident was sunny, the sun was behind the mountains and not affecting visibility. The road was dry and in good condition, visibility was good. I cannot think, as a driver myself of any reason this accident occurred other than the driver of the white van was driving crazy and without responsibility. I get the impression he was in a hurry, he was driving too fast. His overtaking of us all was also crazy and risky. The manner of the driving of the van definitely had an influence on this accident....there was no other vehicles in my opinion who were at fault from this accident...."
 Hugh Drummond is a retired police officer. He was driving north on the A9. His car was on cruise control and was doing a steady 60 m.p.h. He was travelling behind a light commercial vehicle. Just past Drummochter Summit he was overtaken by Mr McLean's white van. The road at that point has a single carriageway in each direction and a 60 m.p.h. speed limit. It was approaching a sweeping right hand bend. The van did a double overtake of Mr Drummond's vehicle and the commercial vehicle. It was on the southbound carriageway for 40-50 yards. He saw it carry on at speed for a mile or so. It then disappeared from view. He thought the van's speed was very much in excess of the speed limit because it disappeared along the mile straight in a matter of seconds. At the time Mr Drummond had thought - because of the van's speed and the way its driver overtook - that it was "an incident waiting to happen". About seven to ten minutes later Mr Drummond came upon the accident scene.
 Justine Stewart was a front seat passenger in Mrs Stewart's BMW. She was 25 years old at the proof and was a medical student. She recalled being in a line of traffic. Her mother braked quite hard - she would not describe it as an emergency stop. There was a noise and a jolt as the BMW was bumped from behind. The bump from behind was a substantial impact but not enough to divert the BMW from its course on the road. Her recollection of the sequence of events was that the bump came first, and it was after that when she was aware of braking and the BMW coming to a stop.
 Ronald McLean was aged 53 at the proof. At the time of the accident he had been employed by Port Services (Invergordon). He had been working in Lockerbie that morning. He had driven a lorry to Grangemouth where he picked up the white van. He was on his way back home to Alness at the time of the accident. Just north of Dalwhinnie he had come across a line of vehicles travelling north ahead of him. At the rear of this line was the camper van. It was travelling at about 50-55 m.p.h. After following it for a while he overtook the camper van and two vehicles in front of it. The southbound carriageway had been clear. The camper van and the other vehicles had been fairly close together - about 15 yards apart. In examination-in-chief he stated there had been a gap between them into which he had pulled in but as the road was still clear he had carried on overtaking. He first saw the Peugeot travelling south when he was back on his own side of the road after the whole overtaking manoeuvre had been completed. He looked in his mirror and saw the camper van come out on to the southbound carriageway and collide with the Peugeot. At least a minute passed between Mr McLean pulling in to his own side of the road and the collision occurring. He did not stop but he contacted the emergency services a little further down the road giving them his name and address. He carried on northwards. He was flagged down by police near Aviemore.
 In cross-examination Mr McLean accepted that he had been in a rush that day to get home - he had been away from home for just over a week. He had overtaken at 60-65 m.p.h., "70 at the most". He clarified that he had overtaken the camper van and the two vehicles in front of it in one manoeuvre. He accepted that he had pled guilty to a contravention of Section 3 of the Road Traffic Act 1988 in the following terms:
"on 24 March 2007 on a road or other public place, namely the A9 road, near Cuaich, by Dalwhinnie you ....did drive a mechanically propelled vehicle, namely a motor van registered number SC02 AEU without due care and attention or without reasonable consideration for other persons using the road or other public place, carried out an overtaking manoeuvre on a number of preceding motor vehicles when it was not safe to do so and the drivers of preceding vehicles required to brake to allow you to return to the correct carriageway and to avoid a collision; CONTRARY to the Road Traffic Act 1988, Section 3 as amended."
Nonetheless, at the proof he did not accept that he overtook when it was not safe to do so. He said he had not had much time with his solicitor on the day he pled. He did not recall seeing the precise terms of the plea. The whole case had been praying on his nerves and he had wanted it over and done with. The road had been clear when he had pulled out and he had been back on his own side of the road before he had seen the Peugeot approaching. He accepted that it would have been reckless to have pulled out in front of an on-coming vehicle and to have pulled in sharply to avoid it, but maintained he did neither of these things. While he did not claim his driving had been perfect he had not done anything careless or dangerous. At the time he had wondered what had caused the camper van to swerve out - but it had had nothing to do with his driving. At the conclusion of his evidence he asked me whether he could say something. He said he regretted what had happened that day. He had gone over it in his head many times. If he was to blame, he regretted what had happened. As a result of the events of that day he now suffered nervous problems.
 P.C. Lemmon prepared a police accident investigation report following the accident. At that time he was 42 years old with 18 years police service. During eleven and a half of those years he had been involved in carrying out collision investigations. He had attended over 200 fatal road traffic accidents. He confirmed, under reference to Rule 105 of the Highway Code, that a gap of 20 yards between cars travelling at 50 m.p.h. was an unsafe stopping distance. Rule 105 provided:
105. Drive at a speed that will allow you to stop well within the distance you can see to be clear. You should
Typical stopping distances
50 mph 15 metres braking distance 38 metres thinking distance = 53 metres or 13 car lengths"
At 50 m.p.h. 2 seconds was the recommended safe gap and 53 metres was the recommended safe stopping distance. A camper van would take longer and further to stop than an ordinary motor car. Most drivers failed to observe the safe stopping distance recommendations. They travelled too close together. A gap of 20 yards at 50 m.p.h. was common, but it was not safe. P.C. Lemmon was clear in his view that Mr McNicoll should have left a greater space than 20 yards between the camper van and the BMW. He considered Mr McNicoll was driving too close to the BMW and that he was not paying sufficient attention to events around him. Mr McNicoll was aware that the white van's driving was liable to result in danger to other road users. His elevated viewpoint should have given him a better opportunity to observe and anticipate events. From his experience of this part of the road P.C. Lemmon thought Mr McNicoll should have seen the southbound Peugeot approaching even if he was partially unsighted by the white van overtaking the vehicles ahead of him. P.C. Lemmon considered Mr McNicoll's decision to steer to the right to be inexplicable. He had had two preferable options. First - the option he thought most people would have taken - to steer to the left where there was a relatively wide and flat grass verge. Second, to run into the back of the BMW. It was clear from the tyre marks left on the road by the camper van that Mr McNicoll had steered to the right before he braked heavily and before the brakes had locked. In summary he thought Mr McNicoll should have been further back from the BMW, should have paid more attention to what was happening around him, and should have steered on to the verge. So far as Mr McLean's driving was concerned, he had overtaken at a place which was not a good overtaking opportunity because of the cut of the bend in the road. There was a sweeping right hand bend bordered to both sides by rock faces which restricted the view round the bend. Although he had managed to return to his own side of the road without colliding with any vehicles, as a result of his overtaking manoeuvre vehicles travelling north had had to brake to assist him to do so.
The parties' contentions
 Mr Mackay accepted that on the evidence Mr McNicoll had been driving too close to the BMW. However, he submitted that in that context I should have regard to P.C. Lemmon's evidence that a 20 yard gap was common between vehicles travelling at 50 m.p.h: it didn't excuse the breach of duty but it was relevant when it came to assessing the degree of culpability. I should not conclude that Mr McNicoll had failed to keep a good lookout. The evidence did not show that he ought to have been aware of the Peugeot's approach. I should not find him at fault for steering to the right rather than to the left. He had been presented with an emergency which had been created by Mr McLean and his steering to the right had been more of a reflex than a conscious choice. The circumstances were such that, in relation to his steering to the right, the agony rule applied (Walker, The Law of Delict in Scotland (2nd ed.), p. 365-6; Robertson v Inspirations East Ltd  CSOH 30, paragraphs , , ; Easdon v A Clarke & Co (Smethwick) Limited  CSOH 29, paragraphs -, , ).
 Mr Mackay submitted that I should find Mr McLean's evidence to be incredible and unreliable. His account that the Peugeot did not appear until about a minute after he had completed the overtaking manoeuvre flew in the face of all of the other evidence. On the issue of whether Mr McLean pulled in front of the camper van and then embarked on a second overtaking manoeuvre, or overtook the camper van and vehicles in front of it in one manoeuvre, I should accept Mr McNicoll's account (which had not been challenged in cross-examination on this point). On the evidence Mr McLean had been driving above the speed limit - at between 60-70 m.p.h. - and had overtaken the vehicles in front of the camper van when it was unsafe to do so. It had been a piece of reckless driving. It had caused the vehicles in front of the camper van to brake to enable Mr McLean to return to the northbound carriageway in time to avoid a collision with the southbound Peugeot. It had created a dangerous situation for other road users. It had set in motion the chain of events which led to the collision of the camper van and the Peugeot. Mr McLean's fault had been far more serious than Mr McNicoll's, and its causative impact had also been greater. Mr McNicoll's culpability was modest. He had been driving a considerable distance behind the BMW. He had not been "tailgating" (cf. Bellingham v Todd 2011 RepLR 68). In the whole circumstances a just apportionment of liability would be 20% to the first defenders and 80% to the second defenders.
 Mr Armstrong accepted that some aspects of Mr McLean's evidence were wholly at odds with all the other evidence. He conceded that his evidence that the Peugeot did not appear until about a minute after his overtaking had been completed "plainly cannot be right". Nonetheless Mr Armstrong submitted that Mr McLean had been doing his best to recollect events after four and a half years.
 Mr Armstrong's primary submission was that the collision between the camper van and the Peugeot had not been caused to any extent by breach of duty on the part of Mr McLean. Rather, he maintained that the sole effective cause of the accident had been Mr McNicoll's driving, which he described as reckless. It was clear that Mr McNicoll had been driving too close to the BMW. His steering to the right - into the path of the Peugeot - had been a reckless act. There was no intelligible explanation for it. He ought to have steered to the left on to the verge or continued in a straight line. Given his elevated position, and the evidence of what other drivers saw, he ought to have been aware of the approach of the Peugeot. His steering to the right could not be excused by virtue of the agony rule. He was driving too close at the time, in circumstances where he had already been alerted to the fact that a situation requiring action by road users in front of him might arise. A number of vehicles had braked at about the same time, but none apart from Mr McNicoll's had collided with a vehicle in front or steered into the southbound carriageway. Mr McNicoll's breach of duty was a novus actus interveniens (Rouse v Squires  1 Q.B. 889; Wright v Lodge  4 All E.R. 299).
 In the event that I was not persuaded that Mr McNicoll's breach of duty was the sole effective cause of the collision between the camper van and the Peugeot, Mr Armstrong's secondary submission was that a greater share of responsibility for it lay with Mr McNicoll than with Mr McLean: and that, having regard to the relative degrees of blameworthiness and causal potency, liability should be apportioned 80% to the first defenders and 20% to the second defenders (Bellingham v Todd; Wright v Lodge).
 Subject to the qualifications I note below, I accept the evidence of Miss Stewart, Mrs Stewart, Mr Probst and Ms Kratz as to the circumstances of the accident. Their evidence was consistent in almost all material respects. I found Miss Stewart to be a credible witness. The accounts by Mrs Stewart, Mr Probst and Ms Kratz were given very shortly after the accident when matters were fresh in their minds. All of these witnesses were independent. It was not suggested that any of them had an interest which might have coloured their accounts; or that I ought to treat their evidence as being other than credible and reliable. There is no reason to question the credibility or reliability of their accounts on essential matters.
 I find Mr McNicoll to be a credible and reliable witness. His evidence and Mr McLean's evidence diverged on the question whether Mr McLean cut in front of the camper van. I do not think it matters who is correct on this issue. It is clear on the evidence that Mr McLean overtook three vehicles in front of the camper van in a single manoeuvre: whether he also overtook the camper van in the same manoeuvre, or had overtaken it and cut in front of it before the manoeuvre, seems to me to be to be of very little import. On either scenario Mr McNicoll was alerted to the presence of Mr McLean and to the manner of his driving. However I prefer Mr McNicoll's account to Mr McLean's on the point. In reaching that view I have had regard to the fact that Mr McNicoll made a much more favourable impression upon me than did Mr McLean, and that his evidence on most material matters is supported by the independent eye-witnesses (but on this point their evidence is neutral or ambiguous). Mr McNicoll's version was not challenged in cross-examination. Indeed in his closing submissions Mr Armstrong did not suggest that Mr McLean's version should be preferred to Mr McNicoll's: his position was that one of the reasons Mr McNicoll had been put on notice "something was happening which might require his attention and might end badly" was that Mr McLean had cut in front of him.
 I reject Mr McLean's account of events in so far as it is inconsistent with the evidence of the other eye-witnesses. In particular, I reject his account that he had completed his overtaking manoeuvre some time before the Peugeot came into view: I am not persuaded that that aspect of his account was attributable to faulty recollection as opposed to a deliberate attempt to minimise his culpability. I found his attempt to distance himself from the plea of guilty which he had tendered to be wholly unsatisfactory.
 One aspect of Miss Stewart's evidence which I consider to be unreliable is the suggestion that the bump came before her mother braked. I think it clear from the evidence of Mr McNicoll and Mrs Stewart that Mrs Stewart braked first.
 I accept P.C. Lemmon's evidence as to appropriate stopping distances; as to the layout of the road and its unsuitability for overtaking at the point where Mr McLean overtook; as to Mr McNicoll steering right before braking heavily and locking the brakes of the camper van; as to the verge to the left being relatively wide and flat; as to three options which were open to the Mr McNicoll when the BMW braked and as to him having taken the worst of the three; as to Mr McNicoll's elevated driving position, the fact he ought to have been alert to the possibility that white van's overtaking might cause other drivers near it to have to react, and that he ought to have been aware of the Peugeot's approach on the southbound carriageway.
 Mr Drummond's evidence was not challenged. I accept it. It may reasonably be inferred that the white van he described was the van driven by Mr McLean. Mr Armstrong did not suggest otherwise.
 It follows that I am satisfied that Mr McLean overtook the BMW and two vehicles in front of it in one overtaking manoeuvre. He was driving at between 60 and 70 m.p.h. He overtook at a point in the road where it was not safe to do so because he could not see far enough ahead. When he was abreast of the BMW and Mr Probst's car the southbound Peugeot was in view. There was a risk of a head on collision. Drivers of vehicles he was overtaking, including the BMW, braked suddenly and hard to assist him to return to the northbound lane. When the BMW braked Mr McNicoll braked and steered to the right to avoid the rear of the BMW. He had been driving too close to it. He then braked hard, hit the offside tail-lights and bumper of the BMW, and continued on to the southbound carriageway and into the path of the Peugeot.
 Some of the witnesses proffered views as to who was responsible for the camper van colliding with the Peugeot; and in some instances witnesses volunteered, or were invited to use, epithets such as "reckless" to describe a driver's conduct. These are, of course, properly matters for the court rather than the witnesses. None of the independent eye-witnesses saw the whole incident from start to finish. The court has heard all the evidence: it is for it, not the witnesses, to draw the appropriate inferences and conclusions from that evidence.
Breach of duty
 I have no hesitation in concluding that Mr McLean was in breach of his duty of care to other road users in carrying out the overtaking manoeuvre. On the evidence it is clear to me that Mr McLean decided to take a chance. He began the overtaking manoeuvre at a point where he could not see sufficiently far ahead to ensure that he could complete it before he met southbound traffic. He continued overtaking after the Peugeot had come into view. Mr McLean should not have taken the risk that he did. He placed the vehicles he was overtaking in a position where the only prudent course was to brake.
 It is also clear that Mr McNicoll was in breach of his duties to other road users. He did not leave a safe stopping distance between the camper van and the BMW. On the evidence he failed to keep a good lookout. He ought to have been aware of the approach of the Peugeot. He ought to have been more alert to the development of the hazardous situation created by Mr McLean's driving.
 In steering to the right rather than taking either of the other two options was Mr McNicoll in breach of his duty of care to other road users? In my view he was. Of course, he had been placed in a situation of danger as a result of Mr McLean's overtaking manoeuvre. However, had he been driving at a safe distance behind the BMW he should have been able to brake without colliding with it: and he would have had more time to react and to decide which way to steer. In the circumstances I do not accept that his breach of duty in steering to the right falls to be excused by virtue of the agony rule. However, when assessing the degree of Mr McNicoll's culpability for this breach it would be wrong to ignore that he was reacting to an emergency which had been created by Mr McLean's breach of duty.
 I turn now to the submission that Mr McLean's driving was not an effective cause of the accident: and that the sole effective cause was Mr McNicoll's driving.
 In considering causation I remind myself of the oft cited dicta of Viscount Birkenhead L.C. in Admiralty Comrs v. S.S.Volute (Owners)  1 A.C. 129 at 144, and of Lord Reid in Stapley v Gypsum Mines Ltd  A.C. 663 at 681:
"..(W)hile no doubt, where a clear line can be drawn, the subsequent negligence is the only one to look to, there are cases in which the two acts come so closely together, and the second act of negligence is so mixed up with the state of things brought about by the first act, that the party secondly negligent, while not being held free from blame under the Bywell Castle rule, might, on the other hand, invoke the prior negligence as being part of the cause of the collision so as to make it a case of contribution." (Viscount Birkenhead).
"In a court of law this question must be decided as a properly instructed and reasonable jury would decide it .... The question must be determined applying common sense to the facts of each particular case. One may find that as a matter of history several people have been at fault and that if any one of them had acted properly the accident would not have happened, but that does not mean that the accident must be regarded as having been caused by the faults of all of them. One must discriminate between those faults which must be discarded as being too remote and those which must not. Sometimes it is proper to discard all but one and to regard that one as the sole cause, but in other cases it is proper to regard two or more as having jointly caused the accident. I doubt whether any test can be applied generally...(I)n this case I think it useful to adopt phrases from Lord Birkenhead's speech in Admiralty Comrs. v. Volute ( 1 A.C. 129 at 144-5...), and to ask was Dale's fault 'so much mixed up with the state of things brought about' by Stapley that 'in the ordinary plain common sense of this business' it must be regarded as having contributed to the accident" (Lord Reid).
 Mr McLean's overtaking created a situation of danger for himself, for the occupants of the Peugeot, and for the occupants of nearby cars on the northbound carriageway. It was reasonably foreseeable that vehicles on the northbound carriageway might not be the recommended distance apart, and that when faced with the sudden need to brake such a vehicle might swerve in an effort to avoid colliding with the vehicle in front. This is not a case where Mr McNicoll's negligence "was of such a character and such a degree as to take it out of the conduct which another driver ought to expect may occur upon the highway" (cf. Rouse v Squires, per Cairns L.J. at p. 896E).
 Mr McNicoll's driving was negligent in the respects I have already identified, but in my opinion it fell far short of the sort of driving which ought to be characterised as reckless. He was closer to the BMW than he ought to have been, but the gap he left was the sort of gap commonly encountered and which many drivers and would consider to be adequate. In relation to lookout, he was distracted by Mr McLean's hazardous driving. While in the whole circumstances it would be incorrect to excuse him for steering to the right, he was faced with a crisis which had been created by Mr McLean and which required him to make a very rapid decision. Viewed in context, his breach of duty in steering to the right, while negligent, had more of the character of an error of judgment than of a decision deliberately or recklessly to court danger.
 I have little difficulty in concluding that Mr McLean's negligence materially contributed to the collision between the camper van and the Peugeot. He was responsible for creating a danger which other drivers then had to react to. His negligence was connected to the collision not merely as a matter of history. It was closely connected to it temporally and spatially. In the language of Viscount Birkenhead and Lord Reid, Mr McNicoll's fault was "so much mixed up with the state of things brought about by" Mr McLean's fault that the latter must be regarded as having contributed to the collision. Mr McLean's fault continued to be an effective cause at the time the camper van steered to the right, collided with the BMW, and went into the path of the Peugeot. This is not a case where a "clear line" can be drawn between Mr McLean's fault and the subsequent fault of Mr McNicoll. Mr McNicoll's fault was not a novus actus interveniens. Approaching the matter broadly and upon commonsense principles, as a jury would probably deal with it, there was no break in the chain of causation between Mr McLean's negligence and the collision with the Peugeot: his negligence contributed to that collision.
 Mr McNicoll and Mr McLean are joint wrongdoers. The court has to assess what each defenders' contribution should be to the damages and expenses payable to the pursuer. Each should make such contribution as the court may deem just (Law Reform (Miscellaneous Provisions) (Scotland) Act 1940, section 3). In Downs v Chappell  1 W.L.R. 426 at 445H Hobhouse L.J. observed (in connection with contribution in England and Wales under section 2(1) of the Civil Liability (Contribution) Act 1978):
"The extent of a person's responsibility involves both the degree of his fault and the degree to which it contributed to the damage in question. It is just and equitable to take into account both the seriousness of the respective parties' faults and their causative relevance. A more serious fault having less causative impact on the plaintiff's damage may represent an equivalent responsibility to a less serious fault which had a greater causative impact."
 Both parties accepted that it was appropriate for the court to have regard to the relative seriousness of Mr McNicoll's and Mr McLean's faults and their causative impact when determining what is just by way of contribution. I have already discussed the respects in which each was in breach of duty. In terms of blameworthiness, Mr McLean's fault was the more serious. In deciding to overtake when and where he did Mr McLean consciously courted danger. His conduct verged on recklessness. On the other hand, it appears to me that Mr McNicoll's fault was more closely and directly connected with the collision (and the damage caused to Kaya McInnes), and had a greater causative impact on it, than did Mr McLean's fault. In the whole circumstances I consider that the just outcome is that the defenders should each bear an equal share of liability for the pursuer's damages and expenses.
 I propose to find each of the defenders liable to contribute fifty per cent of the pursuer's damages and expenses. The only interlocutor I shall pronounce at this stage is to put the case out By Order. That will give parties the opportunity to make any observations they may wish as to the appropriate terms of the interlocutor giving effect to my decision; and to deal with any questions of expenses inter se the defenders which may arise.