National Crime 
Grounds for challenging a will in NSW
Under NSW law, a will may be challenged on one or more of the following grounds. Each ground has distinct legal elements that must be proved. Challenges are often brought on multiple grounds in the alternative — for example, alleging both lack of capacity and undue influence.
Lack of Testamentary Capacity
The testator did not have the mental capacity required to make a valid will at the time of execution. NSW Courts apply the Banks v Goodfellow (1870) test: the testator must understand the nature of making a will, the extent of their property, the claims of those who might expect to benefit, and be free from any disorder of the mind that would poison their affections. Medical evidence — particularly contemporaneous records — is central to capacity challenges.
Undue Influence
The testator's free will was overborne by coercion such that the will does not represent their true intentions. Undue influence is not mere persuasion, advice, or family pressure. It requires proof that the testator was not a free agent. Under NSW law, the person alleging undue influence bears the onus of proof and must meet the Briginshaw standard: clear, cogent, and precise evidence commensurate with the seriousness of the allegation.
Fraud or Forgery
The will is not genuine — it was forged, altered after execution, or procured by fraudulent misrepresentation. This is the most serious allegation in probate law and requires strong evidence, potentially including forensic document examination, handwriting analysis, and testimony from witnesses and the drafting solicitor. The NSW Supreme Court treats allegations of fraud with the utmost gravity.
Suspicious Circumstances
Where circumstances surrounding the will's preparation and execution arouse the Court's suspicion, the evidential burden shifts to the propounder to prove the testator knew and approved the will's contents. Suspicious circumstances may include: the will being prepared by a major beneficiary, the testator being isolated from independent advice, radical departures from longstanding intentions, or execution in unusual circumstances.
Want of Knowledge and Approval
The testator did not know or approve the contents of the will they signed. This is distinct from capacity — a person may have capacity but not understand what a particular document says because it was not read to them or explained properly. Where suspicious circumstances exist, the propounder must affirmatively prove knowledge and approval.
Informal Documents under s 8
Under s 8 of the Succession Act 2006 (NSW), the Court may admit to probate a document that does not meet the formal execution requirements if satisfied the deceased intended it to form their will. A party seeking to propound an informal document must prove this intention. Conversely, a party opposing an informal document must scrutinise the evidence of intention carefully.
Checklist: Does your situation support a challenge?
- The will was made when the deceased was very elderly, unwell, or heavily medicated
- The deceased had a dementia diagnosis or cognitive impairment at the relevant time
- The will was changed suddenly after years of consistent estate planning
- A person who previously received little now receives the bulk of the estate
- The main beneficiary arranged the solicitor or was present when instructions were given
- The deceased was isolated from family and long-standing advisors
- The signature appears irregular or unlike the deceased's known signature
- Earlier wills have disappeared or cannot be located
- The will was made in hospital, a nursing home, or shortly before death
- The witnesses to the will are the beneficiaries or their close associates
If you have ticked several boxes
You should seek legal advice promptly. Multiple red flags warrant thorough investigation. Evidence — particularly medical records and solicitor files — should be secured now. Request urgent advice →
Evidence in NSW will challenges
- Medical records: GP notes, specialist reports, cognitive assessments, medication records for the period around execution
- Solicitor file: The complete file of the drafting solicitor — attendance notes, correspondence, file notes of instructions
- Earlier wills: All previous wills and codicils showing the pattern of testamentary intentions over time
- Witness evidence: Statements from family, friends, carers, and treating doctors about the deceased's mental state and intentions
- Witnesses to the will: What did the attesting witnesses observe about the testator's condition?
- Financial records: Bank statements and property records showing asset holdings at the relevant time
- Timeline: A detailed chronology of health changes, relationship changes, will executions, and hospitalisations
Time sensitivity in NSW
There is no fixed limitation period for challenging a will on grounds of validity in NSW — unlike family provision claims under Chapter 3, which must generally be brought within 12 months. However, this does not mean you can delay:
- Probate may be granted — once probate is granted, the executor can distribute the estate. Recovering distributed assets is difficult.
- Evidence degrades — witnesses' memories fade, records become harder to obtain, and documents may be lost.
- A caveat should be lodged — a caveat prevents probate being granted without notice to you. Lodge it immediately if you suspect a challenge is warranted.
- Delay weakens your position — the Court may refuse relief if you have delayed unreasonably and third-party rights have intervened.
Assess your NSW will challenge
Challenging a will is a significant step. We can assess your grounds, identify the evidence needed, and give you a candid assessment of prospects before you commit to litigation.
Frequently asked questions — NSW will challenges
No. NSW succession law does not recognise unfairness as a ground for challenging a will's validity. A will may be challenged only on specific legal grounds: lack of testamentary capacity, undue influence, fraud or forgery, suspicious circumstances, or want of knowledge and approval. If you believe you have been unfairly left out of a valid will, you may have a family provision claim under Chapter 3 of the Succession Act 2006 (NSW) — but this is a different type of claim and has a strict 12-month time limit from the date of death.
The Briginshaw standard requires that when a court is deciding whether a serious allegation has been proved on the balance of probabilities, it must take into account the gravity of the matters alleged. In the context of will challenges, allegations of undue influence, fraud, and forgery are among the most serious that can be made. The party making such allegations must produce evidence that is clear, cogent, and precise — the more serious the allegation, the stronger the evidence must be. This is not a higher standard of proof, but a recognition that inherently improbable allegations require more persuasive evidence to satisfy the civil standard.
If probate has not yet been granted, you can lodge a caveat with the NSW Supreme Court Probate Registry under Part 78 of the Supreme Court Rules 1970. A caveat prevents a grant of probate or letters of administration from being sealed without notice to you, giving you time to investigate and commence proceedings if warranted. A caveat should not be lodged without legal advice — an improperly lodged caveat can result in adverse costs orders. You should also take steps to secure relevant evidence, including medical records and solicitor files, before they become harder to obtain.