The Use of Prior Capacity Assessments in a Will Challenge

When preparing a Will, testators are encouraged to obtain a capacity assessment where there may be any doubt as to their capacity to make a Will. Those closely associated with the Testator often find some comfort knowing the Testator may be required to undergo a capacity assessment before making a new Will in their latter years, but how effective are those capacity assessments?

A recent High Court decision has provided an important reminder about the role that mental capacity evidence can play in contentious probate disputes. In Croll v The Estate of Margaret Mary Thorpe Deceased and others[1], the court considered whether findings made in earlier Court of Protection proceedings could effectively determine the validity of a later will challenge.

For anyone involved in a disputed will, the case highlights both the value and the limitations of prior capacity assessments.

The background

The dispute concerned a will made by Mr Thorpe in August 2021. After suffering a stroke in 2017, concerns arose about his cognitive abilities. Various legal proceedings followed, including Court of Protection applications relating to lasting powers of attorney and his ability to make decisions.

A key piece of evidence was a psychiatric assessment carried out in 2022, which found Mr Thorpe had significant cognitive impairment and lacked capacity to conduct litigation. The Court of Protection judge later concluded that he lacked capacity when key legal documents were signed in 2021 and expressed strong views that the 2021 will could not stand.

However, when the will dispute was pursued after death, the question was whether those earlier findings automatically decided the probate claim.

Why prior capacity evidence matters

In a will challenge, testamentary capacity is often one of the central issues. The court will consider whether the person making the will understood:

• they were making a will;
• the extent of their assets;
• who might reasonably expect to benefit from their estate; and
• whether any disorder of the mind affected their decision-making.

Where there are contemporary medical records, psychiatric reports, GP notes or formal capacity assessments, they can carry significant weight. Evidence created close to the date a will was signed is often far more persuasive than recollections given years later.

In practice, many successful will challenges are built around a detailed review of historic medical evidence.

What did the Court decide?

The defendants argued that the earlier Court of Protection findings meant the claimant could not pursue the probate claim. The High Court disagreed.

Master Clark held that the Court of Protection did not have jurisdiction to determine the validity of a will while the testator was still alive. The court also identified concerns about whether the Court of Protection could make declarations about an individual’s past testamentary capacity.

As a result, the probate claim was allowed to continue.

Importantly, this does not mean the earlier evidence was irrelevant. In fact, the judgment recognised that the extensive medical and expert evidence considered in the previous proceedings could still prove highly influential when the will challenge is ultimately determined.

The practical lesson for families

For anyone considering a will challenge, this case demonstrates that prior capacity assessments can be extremely valuable, even if they do not automatically decide the outcome.

A detailed assessment carried out before or shortly after a will is signed may become one of the most important pieces of evidence in later probate litigation. Equally, those defending a will should not assume that an earlier finding of incapacity in another context will necessarily invalidate a will.

Each case turns on its own facts and testamentary capacity remains a specific legal test.

If you are considering challenging a will on capacity grounds, it is not enough to simply show that the deceased had dementia, suffered a stroke or was vulnerable. The court will require persuasive evidence that, at the time the will was executed, the deceased lacked the testamentary capacity required by law. Contemporary medical records, expert evidence and formal capacity assessments can be crucial. As Croll demonstrates, previous findings of incapacity may provide powerful evidence, but a successful challenge will still require the probate court to determine whether the legal test for invalidity has actually been met.

[1] [2026] EWHC 2232 (Ch)