I think this case is going to highlight a very significant flaw in legislation nationally and state-based. I am very familiar with psychology and counselling practice, and I can tell you the poor counsellor (and Relationships Australia) would be very concerned about the impact this decision will have on the trust they build with clients in the future.
From my understanding, it is very complex. There is the issue of confidentiality and building trust with clients so they can use the time in counselling and therapy, and have a strong working relationship with their counsellor/therapist. On the other hand, the legislation is contradictory, mainly in the areas of jurisdiction (federal versus state), but also within single Acts (two sections of the Act can say totally opposite things in this type situation). From what I have read, there is no clear cut answer, and the judge is going to have a hard time making the call on this one, as both arguments for and against a forced breach of confidentiality seem valid and within the law.
Duty of care to clients, and the strength of the client-therapist relationship should always take priority, but there are many clear cut times when this would be exchanged in favour of legal requirements (such as child abuse), but this case is not so black and white, and is also very high profile.
This case could lead to some changes to the Act to make it clearer and easier for both counsellors/therapists to apply, as well as legal professionals.
I can imagine many clients, particularly in Family counselling/court orders/divorce proceedings will be asking their counsellors for clarification on what exactly is private and safe from the peering eyes of the courts, and the counsellors been unable to give a clear answer when it comes to court orders.