You have bought defective goods from a supplier, which has caused damage to your property. You refuse to pay for those goods, so the supplier sues you. You defend the claim on the basis that the supplier has given you defective goods, but you do not yet pursue your claim for damages - you want to see how this claim plays out before going to the cost of pursuing your own.
You reach a settlement with the supplier, which makes no reference to any claim for damages you might have, and then commence your own claim against the supplier. But is it too late? Have you lost the opportunity to pursue your claim?
In Port of Melbourne Authority v Anshun Pty Ltd [1981] HCA 45, the High Court laid down the principles which came to be known as "Anshun estoppel". In essence, a party can be prevented from making claims which should have been pursued in the former proceedings.
The test laid down is one of reasonableness. That is, a party cannot raise an issue in subsequent proceedings in circumstances in which it is unreasonable for them not to have raised them in the first proceedings. If it is unreasonable, that party may be "estopped" (or prevented) from doing so, effectively losing the right to make that claim at all.
This is quite different to the principles known as res judicata and "issue estoppel", where a party is trying to re-litigate a matter that has already been decided. With Anshun estoppel, a party can lose the right to litigate a matter that has never been raised before.
This is not a new concept – the Anshun decision was handed down in 1981 – but its principles are just as relevant today. It is important to consider, at an early stage, whether there are any potential claims you may ultimately wish to pursue. If you do not pursue them in the course of existing proceedings, there is a risk you may lose the right to pursue them altogether.
The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.
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