H is for Harman – A-Z of Family Law

The Harman principle stems from an English decision, Harman v Secretary of State for the Home Department [1983] 1 AC 280, which was later affirmed by the High Court in Hearne v Street (2008) 235 CLR 125.

The principle reflects that documents disclosed between parties in litigation cannot be used for any purpose outside those proceedings without the court’s permission.

To paraphrase the Court in Hearne at [96]-[97]: where one party to litigation is compelled by a rule or order of the court to disclose documents or information, the receiving party cannot, without leave of the court, use it for any other purpose. This is sometimes referred to as an implied undertaking to the court of parties, representatives and third parties not to use the documents for other purposes.

In family law, the Harman principle can arise often due to the frequent involvement of parties with criminal law. For example, where a parent involved in litigation involving the care arrangements for their child has also been charged with a criminal offence by the police.

Such a litigant may wish for a report generated within the context of family law proceedings to be disclosed to the police and to the Court in relation to defending their criminal law proceedings. That party must, however, seek the court’s permission to be released from the implied undertaking of the Harman principle.

Harper, Strum and Riethmuller JJ of Division 1 of the Federal Circuit and Family Court of Australia heard appellate proceedings that involved such a request for permission in the proceedings of Kuang & Kuang [2025] FedCFamC1A 31.

The father wished to use a single expert report prepared within the family law proceedings for the purposes of his defence against criminal offences he was charged with. The father believed that facts asserted within the criminal law proceedings were either inconsistent with statements made within that report, or with the opinions of the expert. At first instance, the father was unsuccessful.

Some helpful excerpts from Harper and Strum JJ’s joint judgement are as follows:

• (the document must have) … at least the potential to be important to the proper determination of that case (directly citing Springfield v Bridgelands) [36].
• in considering whether there is a real possibility that the report may contribute to the administration of justice in the appellant’s criminal proceedings, something less than a probability is required [39].
• the “special circumstances” an applicant must demonstrate to be released from the implied undertaking need only be such as to be “sufficient” to justify a departure from the implied undertaking; there is no additional requirement that they be “cogent and persuasive” [40].
• pre-eminent consideration is whether there is a real possibility that the expert reports may contribute to the administration of justice in the father’s criminal proceedings (citing Littlefield & Pemble [2023] FedCFamC1A 198) [42].

A multitude of similar, key decisions were considered and analysed by the Court, particularly Littlefield & Pemble.

The father was granted leave to provide further evidence upon appeal, said evidence essentially being a communication that the expert consented to the father’s proposed course of action.

Ultimately, an outcome was reached:

• the primary judge erred in considering that special circumstances didn’t exist for the report’s release; i.e. the special circumstances were that there was a real possibility that it’s release may contribute to the administration of justice [57].
• the dismissal of the application was “plainly unreasonable, unjust and wrong”[57].
• a “substantial injustice” could result [85].

The judgement goes into considerable depth, but some high-level take-aways are:

1. When multiple sets of proceedings involve litigants, ensure that the Harman principle is front of mind so that the implied undertaking is not breached.
2. Should a departure from the implied undertaking be desired, ensure that there is relevance for the document to be disclosed – a possibility, not probability.
3. Consider obtaining the consent of the author of the document to supplement an application.
4. Be prepared to address why special circumstances apply i.e. would it contribute to the administration of justice?