How to Challenge a Will Due to Dementia

Written by Tanya Waterworth, Digital Content Writer

About Our Legal Expert: This content is produced with oversight by Michael Jefferies, Managing Director who has over 30 years’ legal experience.

Steps for a Contentious Probate Claim

How to challenge a will due to dementia is a sensitive and complex legal matter in England and Wales. If you suspect that a loved one lacked the mental capacity to make a valid will, understanding the process of making a contentious probate claim is crucial.

Our team at Jefferies Claims partners with specialist contentious probate solicitors who offer a No Win No Fee option, along with other flexible funding, as well as a free consultation.

Get in touch with our team today to get started. 

Dementia and Mental Capacity

Dementia is a progressive neurological condition affecting memory, reasoning, and decision-making abilities. When it comes to making a will, the law requires that a person must have mental capacity when making or changing their will. This means they must understand:

• The nature of making a will and its effects.
• The extent of their property and assets.
• The claims of those who might reasonably expect to benefit.
• The potential consequences of their decisions.

If a person with dementia lacked these abilities at the time of signing the will, there may be grounds to challenge it.

Key Legal Principles

In England and Wales, challenging a will on the grounds of dementia generally falls under contentious probate law. The main legal principles include:

1. Testamentary Capacity – A testator must have the mental capacity to understand the will at the time it was made.
2. Undue Influence – The will must be free from coercion or manipulation. Dementia can make individuals more vulnerable to undue influence.
3. Fraud or Forgery – If the will was altered, forged, or misrepresented, it can also be contested.

Signs That Dementia May Have Affected a Will

Identifying signs that dementia influenced a will is a critical first step. Some common indicators include:

1. Sudden or Unexplained Changes – If the will significantly differs from previous versions without clear reason, it may signal impaired judgment.
2. Unusual Beneficiaries – Including people who are not traditionally family or close friends, especially if they were involved in persuading the testator.
3. Inconsistent Decisions – Leaving assets disproportionately to one person over long-term dependents may suggest incapacity.
4. Memory Gaps – Evidence that the person could not recall major assets or family members at the time of the will’s signing.
5. Professional Advice Ignored – If the testator dismissed independent legal advice without clear reasoning, it may also signal compromised capacity.

These signs are not definitive proof but can help establish a case in contentious probate proceedings.

When to Consider Making a Contentious Probate Claim

You may consider challenging a will if:

• You believe the deceased lacked mental capacity due to dementia.
• There is evidence of undue influence or coercion.
• The will was signed under fraudulent circumstances.
• You are excluded from the will despite being a dependent or spouse with potential legal claims.

It is important to act promptly, as there are strict time limits for making a claim in England and Wales. Generally, claims under the Inheritance (Provision for Family and Dependants) Act 1975 must be made within six months of the grant of probate.

Steps to Challenge a Will Due to Dementia

Challenging a will involves several steps which often requires expert legal advice. The process includes:

1. Gather Evidence

Evidence is critical in proving lack of testamentary capacity. This can include:

• Medical records showing a diagnosis of dementia.
• Notes from doctors or care professionals regarding mental capacity.
• Previous wills and documents highlighting changes.
• Witness statements from solicitors, family members, or carers.

2. Seek Legal Advice

A solicitor specialising in contentious probate can assess your claim and advise on the most suitable course of action. They can also handle communications with the executor and other beneficiaries. As this is often an emotionally charged time, they can help reduce family tension.

3. Attempt Mediation or Negotiation

In many cases, disputes can be resolved outside court. Mediation allows parties to negotiate an agreement. This potentially saves time, stress, and legal costs.

4. Issue a Court Claim

If negotiation fails, the solicitor will issue a claim in court. The court will consider:

• The testator’s mental capacity.
• Evidence of undue influence or coercion.
• Consistency with previous wills.

5. Court Assessment

During the hearing, the court may:

• Review medical records and expert witness reports.
• Hear testimony from witnesses who interacted with the testator.
• Examine circumstances surrounding the will’s creation.

The court then decides whether to uphold or invalidate the contested will.

Key Considerations in Contentious Probate Claims

Challenging a will is not a straightforward process and considerations can include:

• Cost – Legal fees can quickly mount up, although they may be recoverable if successful.
• Family Relationships – Disputes often strain family dynamics, so careful handling is essential.
• Evidence Quality – The strength of medical records, witness testimony, and legal documents can make or break your case.
• Time Limits – Acting promptly increases your chances of success before evidence is lost or misplaced.

A solicitor can guide you through these issues and help balance financial, emotional, and legal factors for the most successful outcome for you.

Expert Evidence and Medical Reports

Medical evidence plays an essential role in dementia-related will disputes. Experts can provide:

• An assessment of mental capacity at the time the will was signed.
• An opinion on the progression and impact of dementia on the testator’s decision-making.
• Clarification of whether the testator understood the consequences of their will.

Courts give significant weight to expert testimony, making it one of the strongest forms of evidence in such claims.

Protecting Your Rights as a Beneficiary or Dependent

Even if a will excludes you, you may have rights under:

• The Inheritance (Provision for Family and Dependants) Act 1975 – allows spouses, former spouses, children, and dependents to claim reasonable financial provision.
• Intestacy rules – if a will is declared invalid, the estate may be distributed according to intestacy laws.

Challenging a will ensures that vulnerable individuals with dementia are not unfairly exploited or coerced.

Practical Tips When Considering a Will Challenge Due to Dementia

1. Document Everything – Document conversations, unusual behaviour, or signs of dementia.
2. Act Quickly – Early action strengthens evidence and preserves witness memories.
3. Engage Specialists – Contentious probate solicitors have experience navigating complex cases.
4. Consider Mediation First – Reduces emotional and financial costs.
5. Focus on Evidence, Not Emotion – Courts prioritise proof of incapacity over family disputes and grievances.

Contact Our Team

Challenging a will due to dementia in England and Wales requires recognising the signs of diminished mental capacity, acting promptly, and seeking expert legal and medical advice.

Our partner panel firms can guide you through the process of what to do next. Call us now at 0333 358 2345 or contact us online to arrange your free consultation.