"The submission made on behalf of the appellant is to the following effect. First, it is submitted that the ordinary fluctuations in property values could hardly explain the increase in the value of the property between the date of trial and the date of sale. It is submitted that the evidence of the sale price plainly could not have been obtained with reasonable diligence for use at the hearing, since the property did not sell until February 2006.
It is submitted that the principles which should apply are those discussed by the House of Lords in Mulholland v Mitchell [1971] AC 666 and accepted by this Court in Knight v Anderson (1997) 17 WAR 85. Those principles are broadly to the effect that the discretion of the Court of Appeal to admit new evidence as to matters occurring after the date of trial is one of "discretion and degree". The principles which require to be balanced are that there should be finality in litigation on the one hand, and on the other that in exceptional circumstances such as where it might be said that 'basic assumptions at the trial had been falsified', it may be just to admit such evidence. Further, it is to be expected that courts will allow fresh (or new) evidence when to refuse it 'would affront common sense, or a sense of justice' (Mulholland, per Lord Wilberforce at 679 - 680, Knight per Malcolm CJ at 90). Accepting those principles, it is my view that this is a case in which the new evidence should not be admitted.
The appellant's proposition that the value of the Mundijong property had dramatically increased since the date either of trial or of judgment, cannot be accepted as being necessarily accurate. There is no evidence before me suggesting what portion of the increase in value is attributable to the period between trial and sale, rather than between valuation and trial.
By the date of trial, it must have been obvious to all parties that the valuation which had obtained was of the order of 18 months out of date. The appellant must have been broadly familiar with the location, since she had lived there many years earlier. There is no explanation in the appellant's affidavit as to why it was that she was prepared simply to accept that earlier valuation. This was not, it seems to me, a case in which there was a 'basic assumption' common to both parties, reasonably made, as to the value of the property. Rather, it was a matter which the appellant seems content not to have explored.
I was informed from the Bar table, without opposition, by counsel for the appellant, that the appellant's solicitors had at one stage raised with the solicitors for the respondents the desirability of obtaining a further valuation. However, in the face of some opposition or lack of co-operation from the respondents' solicitors, that issue had not been pursued. It seems to me that it does not matter whether the appellant had not considered the question of the accuracy of the valuation at all, or whether she had suspected it to be inaccurate but had not pursued the matter. In either event, there was a decision on the part of the appellant to conduct the trial on the basis of the earlier valuation.
In those circumstances, it seems to me that it would be an affront to commonsense and to justice to permit the adducing of further evidence of valuation on the appeal, merely because at some stage between the obtaining of the original valuation in 2004 and the sale of the property in 2006, its value had substantially increased. In any trial involving the valuation of assets, it is likely that the value of those assets will fluctuate over time and that at the date of an appeal, values will not be precisely the same as those either at trial or at some earlier time. The situation is not confined to real property. An estate consisting wholly of shares may fluctuate very significantly in value between one date and another. Nor is the situation confined to actions of this kind. In personal injuries actions, the cost of treatment will fluctuate, average earnings in a plaintiff's occupation will fluctuate, and the plaintiff's condition may vary either for better or worse in a manner not clearly foreseen by treating physicians. The Court should be slow to permit the reopening of such an issue, merely because some facts assumed to be correct at trial have altered by the date of an appeal.
It is not possible to lay down any clear guide as to when evidence of a fluctuation in value should be admitted. However, the cases recognise that it must be only in 'exceptional' circumstances that such further evidence should be admitted. These circumstances have not been demonstrated to be exceptional. Any person with any ordinary understanding of property values in Western Australia would have expected an increase in value between 2004 and 2005, and again between 2005 and 2006. The appellant chose not to explore this issue at trial at all. In those circumstances, there is no injustice to the appellant in having the appeal conducted on the basis of an assumption which she was content to make."