No complaint is made by the appellants about the judge's method of making a single order in apportioning the costs. It was certainly open to his Honour to do so. Under r 63.04, the judge might have awarded costs in relation to particular questions or parts of the proceeding. We think it appropriate however, with respect, to observe that the approach taken by his Honour, of fixing of a certain proportion of a party's costs which should be paid by another party, has much to commend it.
In fixing costs a superior court may treat 'heads of controversy as units of litigation' and give directions to the taxing master in relation to them, such units not being circumscribed by pleadings, causes of action or issues capable in themselves of leading to the granting of relief. But to avoid the complications of taxation resulting from making orders recognising the entitlements to costs of a party on each action on which they were successful, the orders may be notionally set off against each other or other adjustments made so as to produce an order for a proportion of one party's costs. This approach to costs orders where an action has had mixed success has been followed in a number of cases. In Hughes v Western Australian Cricket Association (Inc), Toohey J had regard to the fact that the plaintiff had succeeded on some issues but failed on others, but concluded that: 'it would be unsatisfactory to attempt to apportion issues and leave the fixing of costs of those issues to the taxing officer. That would impose a very great burden on him and upon the parties' legal representatives.' In our view, the judge's approach to the apportionment of costs was particularly apposite in this case, having regard to the multiplicity of parties, actions, and issues, and the mixed success enjoyed by the plaintiffs. (Footnotes omitted.)