The "Total" was mathematically the addition of the $4,306,601.26 and $1,148,512.86. The CPI figure represented the appellant's escalation claim.
40 The appellant's substantive argument for departure from the terms of the contract for expert determination, subject to the two supporting arguments to which I will come, was as follows.
41 The expert determined "value of work" of $4,362,588.00. The figure of $4,306,601.26 in the spreadsheet plus the CPI figure of $55,796.69 came to a total of $4,362,397.95. However, the CPI figure of $55,796.69 was the same as the CPI figure for 519 poles shown on a previous spreadsheet. It was necessary to add a CPI figure for a further pole, and materials earlier provided to the expert by the appellant asserted a CPI figure for the last of the poles supplied or to be supplied of $190.93. Adding this to the $4,362,397.95 brought an amount of $4,362,588.88. If the 88 cents were ignored, this was the value of work as determined, namely, $4,362,588.
42 It should be concluded, according to the argument, that the expert had arrived at the value of work of $4,362,588.00 in that way, that is, by taking from the spreadsheet the figures for Schedule Poles Supply and Installed and CPI and adjusting the CPI figure by an additional CPI amount appropriate to the 520th pole. In doing this, it was said, the expert left out of account the claims in the spreadsheet under the headings "Manufacture and Supply of Schedule of Rates Items" and "New Products Not Included in Tender" to the value of $1,148,512.86.
43 In relation to the same argument the trial judge referred at one point to "an uncanny coincidence in the ability of the plaintiff to add together 1, 2, and 3 in the manner earlier referred", and the expression "uncanny coincidence" was repeated many times in the appellant's submissions in the appeal. I doubt that the emphasis on the expression, which clearly enough came into his Honour's vocabulary from the appellant's submissions, was of assistance. Coincidence requires two things that coincide. In the present context one is the amount of $4,362,588.88 at which the appellant arrived by adding together the three figures of $4,306,601.26, $55,796 and $190.93, and the other is the figure of $4,362,588.00 in the determination. To describe the similarity as a coincidence means no more than that the figures are similar. To describe it as an uncanny coincidence risks begging the question, by starting from the position that the similarity was because the expert had arrived at the value of work figure in the same manner the appellant arrived at its amount. The appellant's argument, of course, was that the coincidence called for the inference that the expert had done this. The word "uncanny" was part of its argument, but the trial judge was not satisfied that the coincidence went beyond hypothesis or conjecture and matured into an inference capable of forming the basis of a finding of fact.
44 In a supporting argument not put to the trial judge the appellant referred also to the "less retention" figure of $120,456.95 in the determination. It argued that the expert's task had not included arriving at a retention amount, but he had done so; further, it could be seen that he had done so erroneously. The point of the argument was that, if the expert had taken on a task beyond that required of him, and then got it wrong, it should more readily be accepted that he had erred in departing from the contract for expert determination in determining the value of work figure. The appellant said that the fact that the expert had acted in this way was relevant within s 55 of the Evidence Act 1995 (NSW) in that it could rationally affect the assessment of the probability of departure from the contract for expert determination in determining the value of work figure.
45 The respondent accepted that the expert went beyond the task required of him in determining the retention amount. In my opinion, however, little significance should be attached to the fact that he did so.
46 The contract for expert determination was imprecise: to repeat, it spoke of "the matters in dispute arising out of or in connection with the contract to be identified in the parties submissions to the expert". The respondent accepted that the submissions to the expert did not identify a dispute over retention. On one view, the contract for expert determination called only for determination of discrete disputes over amounts claimed by the appellant to be payable but disputed by the respondent. But it was clear that the parties intended that, whether or not it was strictly required by the contract for expert determination, the expert should arrive at an overall value of work which would include undisputed amounts payable by the respondent to the appellant. Mr Barnes agreed in the evidence earlier referred to that he expected the expert, in arriving at his value of work figure, to take into account items which were in agreement and items which were not in agreement. Further, as is apparent from the determination of 19 January 1999 and more particularly the determination of 9 February 1999, what had been paid under the contract for the street poles was taken to be part of the expert's task even if not itself a matter of dispute, and without being confined to payment for items in dispute. The expert's task as conceived at the time was in fact wider than the terms of the contract for expert determination might have suggested.
47 In the circumstances it is understandable that, although not in terms part of his task, after expressing his determination as a value of work figure less payments the expert should have gone on, either in order to avoid misinterpretation that the entire balance was immediately payable or simply following routine industry practice, to state a retention amount and express an amount which was immediately payable. To the extent he went beyond his task, it really says nothing as to the departure from the contract for expert determination necessary for the appellant's substantive argument.
48 Before the trial judge neither party had been able to offer an explanation of the calculation of the retention amount. This perhaps was why the supporting argument was not put to the trial judge. The appellant proffered an explanation on appeal.
49 The contract for the supply of the street poles provided for retention of 5 per cent of the contract sum. The contract sum was relevantly defined as the contract sum where the respondent accepted a lump sum or the sum ascertained by calculating the products of rates and quantities, in each case excluding any additions or deductions required to be made. The retention amount of $120,456.95 in the determination was mathematically 5 per cent of $2,409,139. The appellant's non-conforming tender had put forward $143,905 for set up, $955,117 for supply of 180 street poles with footings and installation by others, $1,310,117 for supply and installation of the same street poles with footings by others, and rates for the supply and installation of further street poles. The three lump sums totalled $2,409,139. The appellant submitted that it should be inferred that the expert had calculated the retention amount as 5 per cent of the total of these lump sums, and that he had erred in doing so: first, because the figures were for 180 street poles only, not the 520 poles the subject of the determination; and secondly because, although it was not plainly stated, the second and third figures were necessarily alternatives.
50 The respondent accepted that the appellant had "demonstrated … as a matter of probability" that the expert was not correct in his calculation of the retention amount. The error was potentially of more significance than arriving at a retention amount at all, in that it was an egregious error not understandable as a benevolent or routine addition to arriving at the value of work figure. But what might it signify?
51 The respondent submitted that neither arriving at the retention amount nor getting it wrong assisted the appellant's argument for departure from the terms of the contract for expert determination in determining the value of work figure. That the expert addressed an irrelevant matter did not vitiate his determination of the relevant matter. The demonstrated error was not as to the value of work, and the fact that an error was made did not by itself or in conjunction with anything else support the error essential for an affirmative answer to the principal question. The respondent said that the supporting argument was no more than that the expert had a propensity to make mistakes, but that reasoning of that kind was impermissible and in any event a propensity had hardly been established.
52 In my opinion the supporting argument in this respect provides but little support for the appellant. The appellant correctly did not put it as a propensity argument - if there is such a thing as a propensity to make mistakes, error in relation to the retention amount was not enough to establish propensity. What happened in relation to the retention amount is a beneficial reminder that experts can make mistakes, and an indication that the expert on a discrete subject may not have had the mastery of the subject otherwise to be expected. I am content to have the reminder and the indication in mind when considering the possibility or probability that the expert's mastery of the materials before him in arriving at the value of work was wanting and he made the error for which the appellant contended.
53 For a further supporting argument not put to the trial judge the appellant proffered a calculation which it said demonstrated that it had an indisputable entitlement to be paid $4,801,558.38. There were three components in the calculation. The first was said to be a calculation of rates and quantities in relation to undisputed items from the respondent's non-conforming tender. The second was a tabulation of amounts said to have been agreed between the appellant and the respondent in relation to disputed items in the course of the determination and in correspondence between them. The third was a tabulation of amounts said to have been offered by the respondent in relation to disputed items where agreement had not been reached. To this was added the CPI adjustment of $55,796.89. The appellant argued that, if it had the indisputable entitlement, there must have been error in the expert's determination of a lesser amount as the value of work.
54 The respondent took issue with the calculation, and said also that if the argument had been raised before the trial judge it would have had the opportunity to meet it by evidence, rather than be required to challenge a calculation lately constructed from incomplete materials. In my opinion there was substance in both these responses to the argument. I am not satisfied that the appellant's calculation was soundly based, and it is sufficient that, without going through the figures, I consider that the respondent demonstrated that significant components of the calculation of rates and quantities in relation to allegedly undisputed items were in fact in dispute. It is otherwise sufficient to refer to the principles in Suttor v Gundowda Pty Ltd and Coulton v Holcombe to deny the argument to the appellant.
55 To return to the appellant's substantive argument, it must be remembered that in this case the principal question is a question of fact. The appellant must establish on the balance of probabilities that the expert arrived at the value of work in the manner put forward in the argument, and thereby left out of account the claims to the value of $1,148,512.86.
56 It could not lightly be found that the expert arrived at the value of work in the manner suggested. It is inherently improbable that he would have taken the figure for street poles supplied and installed from the first two-thirds of the spreadsheet page, passed over the two subsequent headings and the figure produced under them, ignored the "Total" figure which clearly showed that what was under the two headings was additional, and then taken the very next CPI figure. I bear well in mind the reminder and indication in the appellant's supporting argument. The improbable occurs. But the scale of improbability in relation to value of work to my mind is much greater than in relation to the retention amount. If the appellant's argument be correct, the expert did not just add something irrelevant to his prescribed task and in doing so misread a contract on a matter on which he had not received submissions. He inexplicably left out of account claims to a large sum of money clearly apparent from the spreadsheet and the subject of extensive submissions.
57 The appellant said that arriving at the value of work in the manner suggested was really not inexplicable. The explanation, it suggested, was that a number of the claims in the spreadsheet under the headings "Manufacture and Supply of Schedule of Rates Items" and "New Products Not Included in Tender" had been agreed, and so the expert ignored the claims under those headings because they were not in dispute.
58 There are at least two reasons why this is a highly unlikely explanation. First, as earlier noted the parties intended that the expert should arrive at an overall value of work which would include undisputed amounts payable by the respondent to the appellant. The intention was given effect through the spreadsheet including undisputed amounts as well as disputed amounts, and must have been shared by the expert. The expert should therefore not have ignored claims because they were not in dispute. Secondly, not all the claims in the spreadsheet under the two headings had been agreed. As the appellant acknowledged in the appeal, many of the claims in substantial amounts were disputed to the end. Even if he had been minded to ignore claims not in dispute, the expert should not have ignored the claims under the two headings entirely. The expert is unlikely to have acted as suggested given the extensive submissions, which could not have left him unaware of the disputed claims. The suggested explanation leaves inexplicable error.
59 The appellant's argument depended on the coincidence between the figure of $4,362.588.00 in the determination and the derived figure of $4,362,588.88. The coincidence required that the 88 cents be ignored. Why should this be done, said the respondent, when all other figures in the determination had been expressed to the last cent? Why would the expert have rounded the figure off if he had derived it in the manner suggested, and if he had rounded it off why would he have rounded it down rather than up? The round figure suggested that the expert had arrived at it in some other way, in which there was an element of estimation or reasonable charge which made a value of work to the last cent inappropriate. In my opinion the respondent's points are well made, albeit not such as should govern the factual finding.
60 There are other and weightier considerations against the finding sought by the appellant. They may be summarised as follows.
61 First, if the expert acted in the manner required by the appellant's argument he must have accepted to the full the appellant's claims in relation to the supply and installation of street poles resulting in the figure of $4,306,601.26 for the 520 poles. The claims included items for variations and extras, of the same nature as many of the items under the two later headings giving rise to the $1,148,512.86. The trial judge recorded that the parties remained in dispute to the end about the value of work and how individual items were to be valued, and in addition that the respondent continued to submit that many of the appellant's recent submissions should be disregarded because of their contents and/or the lateness of their delivery. He recorded that on the evidence of Mr Barnes many of the claimed items making up to the $4,306,601.26 "remained in dispute right up until 03.05.99". Experience teaches that it is unlikely that the appellant's claims resulting in the figure of $4,306,601.26 were accepted in their entirety.
62 Secondly, the trial judge also recorded that the appellant's categorisation of items was "without warrant in the contract or otherwise logical". This was not demonstrated to us in the appeal, but the appellant did not dissent from it. If the expert acted in the manner required by the appellant's argument, he must have accepted some items but passed over others either because of the unwarranted and illogical categorisation or in disregard of items of the same nature in different categories. Again, the improbable occurs. But that would be high on the scale of improbability, particularly when the submissions can not have left the expert unaware of the extent of the appellant's claims.
63 Thirdly, if the appellant's argument be correct the expert must have appreciated that the CPI figure of $55,796.89 had been calculated by reference to 519 street poles rather than 520 street poles, and then sought out an appropriate adjustment. This would have required an appreciation of the calculation of the CPI figure. The calculation of the CPI figure included escalation with respect to a number of the items making up the amount of $1,148,512.86. An appreciation of the calculation of the CPI figure would be expected to have included that fact. It is unlikely that the expert wholly disregarded the items for which he allowed escalation, and it is scarcely conceivable that he paid regard to them for one purpose but not for another.
64 Fourthly, the "less paid" amount of $2,455,292.35 in the determination included payments for items included in the $1,148,512.96. The figure came from the consent determination of 9 February 1999, and so may not have been the subject of detailed consideration by the expert. It is unlikely, however, that he did not appreciate that payments had been made with respect to some of the items. The same comment as above may be made.
65 Some of the matters in dispute involved estimation or a reasonable amount. It was quite possible for the expert properly to reach a value of work in a round sum. As the parties' chosen expert, he was to take into consideration the materials provided to him and make his determination using his expertise, and there were a large number of possible combinations of his resolution of the disputes and of components in the value of work figure - it could not be said, and except by the second supporting argument the appellant did not attempt to say, that arriving at a value of work of $4,362.588.00 could not be one such combination.
66 The figure of $4,362.588.00 has contractual standing, unless successfully challenged, as a final and binding determination. A successful challenge by a finding of fact requires more than conjecture. It requires "a satisfactory inference, even though resting on a balance of probabilities": the words are those of Dixon CJ in Holloway v McFeeters (1956) 94 CLR 470 at 476-7. In Seltsam Pty Ltd v McGuinness (2000) 49 NSWLR 262 at 275 Spigelman CJ said that the common law test of the balance of probabilities is not satisfied by evidence which fails to do more than establish a possibility. His Honour referred to the distinction between permissible inference and conjecture, noting that it was often difficult to distinguish between them and that there is no bright line division. I will not repeat the cases cited by his Honour. In the present case I am not persuaded that there is more than possibility or conjecture, or that it should be found that the expert arrived at the figure in the manner required by the appellant's argument. There is coincidence, but not an uncanny coincidence in the sense of one calling for that inference.