Fishing for Facts: When Subpoenas Go Too Far in Family Law Disputes

📘 Introduction

The Federal Circuit and Family Court of Australia's decision in Mertz & Mertz (No 3) [2025] FedCFamC1F 144 is a detailed and pivotal ruling that explores the bounds of subpoena power in the context of a high-conflict family law proceeding. Justice Berman considered whether leave should be granted to the wife to issue subpoenas for medical and employment records of the husband. Central to the case were issues of relevance, admissibility, and whether the subpoenas constituted a fishing expedition. The ruling draws a firm line between genuine forensic inquiry and speculative document requests, offering significant guidance on the strategic use of subpoenas.

🧾 Facts and Issues

Facts:

• The parties are embroiled in a contentious parenting and property dispute involving three children.
• The wife sought leave to issue subpoenas for the husband’s medical and employment records, alleging relevance to his capacity to parent.
• The husband opposed the subpoenas, particularly concerning their inspection and potential for misuse.

Issues:

1. Should the Court grant leave for subpoenas regarding:

• The husband's medical records (from various health services and a clinical psychologist)?
• The husband's employment records (from PP Pty Ltd)?

1. Do the subpoenas have sufficient relevance, or do they amount to impermissible “fishing”?
2. Should the husband have the right to first inspect the documents before potential inspection by the wife?

⚖️ Application of Law to the Facts

1. Legal Framework

Justice Berman extensively applied principles from Hatton v Attorney-General (2000) FLC 93-038, which established that subpoenas must be relevant, non-oppressive, and not a fishing exercise. Other precedents included:

• Martin & Martin (No. 2) [2014] FamCA 232
• Dupont v Chief Commissioner of Police (2015) FLC 93-648
• Lucas Industries Ltd v Hewitt (1978) 18 ALR 555

The judge emphasized a three-stage process for subpoena review (Hatton & Waind framework):

1. Obeying the subpoena and addressing objections.
2. Court deciding whether the documents should be inspected.
3. Admissibility of the documents.

2. Employment Records

The wife's claim that the husband's departure from PP Pty Ltd could evidence mental instability or aggressive conduct was deemed speculative. The judge noted:

• The husband was already ordered to produce relevant employment documents (e.g., resignation, financial records) under prior discovery orders (¶38).
• There was no credible link between employment termination and parenting capacity.
• The subpoenas were “confused”, lacking direct relevance and instead probing for potentially damaging character evidence (¶33–45).

Finding: Leave refused for subpoena to PP Pty Ltd (¶61).

3. Medical Records

The wife referenced the husband’s suicidal ideation (¶49) and sought medical and therapy records. The court evaluated:

• Whether those records bore directly on the husband’s parenting capacity.
• The absence of an assertion that the husband posed an unacceptable risk to the children (¶35, ¶51).
• Lack of evidence connecting the husband’s mental health to parenting abilities or any specific incident of concern.

Justice Berman allowed subpoenas to:

• QQ Health Service
• Dr RR (clinical psychologist)

… but only with protective measures: the husband has a 7-day first inspection window and the right to file objections (¶59–60).

However, the subpoena to MM Health Service was disallowed due to lack of evidence any relevant records existed, rendering the request purely speculative (¶56–58).

🧑‍⚖️ Judgment Analysis and Reasoning

Justice Berman found that:

• Subpoenas must not be used as a substitute for discovery (¶46).
• There must be a legitimate forensic purpose and clear relevance—not merely suspicion or belief that something “useful might turn up” (¶26–27).
• The wife’s application, particularly regarding employment and additional medical records, failed to meet that threshold and instead constituted a classic “fishing expedition” (¶47).

He reiterated the risk of harassment, third-party burden, and improper discovery practices that subpoenas may invite if unchecked.

The reasoning aligns closely with the test from Hatton v AG and Andrew Garrett Wine Resorts v NAB (No 6) (2005) 92 SASR 419 emphasizing that subpoenas must demonstrate more than a remote chance of usefulness.

📌 Take-Home Lessons

• Relevance is Key: Subpoenas must have a direct and apparent link to the issues in dispute. Vague suspicion is insufficient.
• Discovery ≠ Subpoena: Subpoenas cannot fill the gap when a party fails to properly pursue or respond to discovery.
• Protective Measures Matter: Courts can and will impose inspection protocols (like first review rights) to balance fairness and privacy.
• Fishing Expeditions Will Fail: Courts are alert to speculative and intrusive attempts at evidence-gathering without firm grounding.