(1) Roads and Traffic Authority v Ryan & 2 Ors (2) Blue Mountains City Council v Ryan & 2 Ors (No 2)

The parties involved were the Roads and Traffic Authority and the Blue Mountains City Council (the appellants) and Ryan and two other respondents. The dispute concerned the restitution of money paid by the respondents under a judgment that was subsequently set aside. The matter came before the Court of Appeal of New South Wales.

The primary legal issue before the Court was the appropriate rate of interest to be applied to the sum ordered to be repaid to the respondents. Specifically, the Court had to determine whether the interest should be calculated according to the rates prescribed by Schedule J of the Supreme Court Rules 1970 (NSW) or by some other method, considering the principles of unjust enrichment.

The Court reasoned that the power to order the repayment of money paid under a judgment that has been set aside is a power to make consequential orders to do justice between the parties. While Schedule J provides a default rate of interest, it is not necessarily the only or appropriate rate in all circumstances. The Court considered that the principle of unjust enrichment, which underpins the obligation to repay, suggests that the respondents should be compensated for the loss of use of their money. However, the Court found that there was no basis to depart from the statutory rate prescribed by Schedule J, as it represented a reasonable and readily ascertainable measure of the cost of borrowing or the return on investment.

The Court ordered that the appellants pay to the respondents interest on the sums paid under the original judgment, calculated at the rate prescribed by Schedule J of the Supreme Court Rules 1970 (NSW) from the date of payment until the date of repayment.