A Tale Of Two Wills

What Erez v Jooste-Jacobs Reveals About Testamentary Capacity and Undue Influence

Challenges to the validity of a Will often begin with the same question: does the document truly reflect the testator’s wishes?

Concerns about undue influence or a lack of testamentary capacity can cast doubt on the legitimacy of a Will and, in some cases, lead to it being declared invalid. Yet although such allegations are common in estate litigation, they are notoriously difficult to prove.

The recent Queensland Supreme Court decision in Erez v Jooste-Jacobs [2026] QSC 143 provides a compelling illustration of how courts approach that question when allegations of testamentary incapacity and undue influence are raised. The case involved two contrasting Wills, executed five years apart, each painting a dramatically different picture of the Testator’s intentions.

Two Wills, Two Very Different Outcomes

The Testator died in 2023 at the age of 93. Her primary asset was a residential property in Cairns. Under a Will executed in 2015 (2015 Will), she purportedly appointed the “King of Iran” as executor and left her estate to the sons of an acquaintance (the Plaintiff), who were described as “princes” because of claimed connections to the former Iranian royal family. Five years later, however, she executed a new Will leaving her entire estate to her son (2020 Will).

Following the Testator’s death, proceedings were commenced by the Plaintiff seeking to have the 2020 Will revoked and for the 2015 Will to be declared as the last Will of the Testator. The Plaintiff alleged that the later Will had been procured through undue influence and executed when the Testator lacked testamentary capacity. The administrator of the Testator’s estate rejected those allegations and contended instead that the 2015 Will was itself the product of undue influence.

Testamentary Capacity: More Than a Medical Diagnosis

One of the central issues concerned testamentary capacity. The Court applied the longstanding principles from Banks v Goodfellow, requiring that a testator understand the nature and effect of making a Will, appreciate the extent of their property, and comprehend the claims of those who might reasonably expect to benefit from the estate.[1]

Testamentary capacity is ultimately a practical question grounded in the facts of the particular case. A person may suffer from illness, memory issues or mild cognitive decline and still possess the capacity required to make a valid Will.[2] What matters is their ability to understand the testamentary act at the time the Will is executed.

The Plaintiff relied on evidence that, prior to execution of the 2020 Will, the Testator had achieved low scores on cognitive testing and that a doctor had assessed her as suffering severe cognitive impairment in 2017. Viewed in isolation, such evidence may appear compelling.

However, the Court took a broader view. Contemporary medical records, expert geriatric evidence and subsequent assessments demonstrated that, despite her age, blindness and certain cognitive difficulties, the Testator retained sufficient understanding of the decisions she was making. Significantly, the medical practitioner who had earlier questioned her capacity later revised that opinion following further examination.

The High Bar for Undue Influence

If proving a lack of testamentary capacity is difficult, establishing undue influence is often even harder.

The Court reaffirmed that undue influence requires proof of coercion sufficient to overbear the free Will of the testator.[3] Mere persuasion, encouragement, family pressure or involvement in the Will-making process will not suffice.[4] The focus is not whether a person influenced the testator, but whether they effectively replaced the testator’s intentions with their own.

This distinction is critical because influence naturally exists in many family relationships. Elderly individuals commonly rely on family members for care, transport, communication and decision-making support. Courts therefore approach allegations of undue influence cautiously, recognising that influence alone is not inherently improper.[5]

The Plaintiff alleged that the Testator was vulnerable by reason of cognitive impairment and that the 2020 Will was procured through the influence of those assisting the Testator after she severed ties with  both her niece and the Plaintiff.

However, the Court found no evidence capable of demonstrating the level of coercion required to invalidate the 2020 Will. Instead, the evidence showed that the Testator had sought independent legal advice and had consistently expressed a desire to benefit her son. Those facts were fundamentally inconsistent with the narrative put forward by the Plaintiff that the 2020 Will was the product of undue influence.

Conversely, the Court expressed considerable concern regarding both the circumstances in which the 2015 Will was prepared and aspects of the Plaintiff’s evidence. The Court found that the Plaintiff and other members of the Testator’s family, particularly her niece, had made numerous attempts to document the Testator’s capacity for the purpose of executing the 2015 Will. However, after the Will had been signed, those same individuals sought to portray the Testator as having lost capacity in order to prevent her from changing it.

A statement, written and signed by the Testator before her death, stated that she had been physically mistreated by and under the control of her niece for several years but had taken steps to regain her independence, including seeking legal assistance to draft her final Will. The statement affirmed that she neither approved of nor had knowledge of the contents of the 2015 Will and that she had signed it without understanding its contents at the urging of her niece.

Key Takeaways

The ultimate outcome was unsurprising. The Court upheld the validity of the 2020 Will, finding that the Testator possessed testamentary capacity and executed the document freely and voluntarily. Significant weight was placed on the contemporaneous expert evidence, the straightforward nature of the estate, the involvement of independent solicitors and the consistency of the Testator’s expressed intentions in benefitting her son.

Had the Testator not survived to execute the 2020 Will, the focus of the litigation may well have been the validity of the 2015 Will itself. The Court expressed significant concerns about the conduct of the Plaintiff and other family members, whose involvement suggested a considerable degree of influence over the Testator at the time. Against that backdrop, it is difficult not to question whether the stringent requirements for proving undue influence may have been met had the earlier Will been the one under scrutiny.

Ultimately, Erez v Jooste-Jacobs serves as a reminder that indications of cognitive impairment do not necessarily equate to testamentary incapacity, nor does influence amount to undue influence merely because it exists. The Court’s task is to determine whether the Will represents the free and informed intentions of the testator at the time it was made.

[1] Banks v Goodfellow (1870) LR 5 QB 549 at 565.

[2] Ibid per Cockburn CJ at 566.

[3] Tobin v Ezekiel [2011] NSWSC 81; Petrovski v Nasev, Re; Estate of Janakievska [2011] NSWSC 1275.

[4] Hall v Hall (1868) LR1P&D 481 at 482.

[5] Ibid.

Benjamin Kett
Solicitor