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What happens if someone who doesn’t have capacity makes a Will?

Challenging a Will: Lack of Testamentary Capacity




Zoe Davis – Trainee Solicitor

When making a will, a person can leave their money, house and other assets to whomever they would like. There is no requirement for them to leave it to their spouses, partners or children.

However, just because a person has made a will, doesn’t mean that it cannot be challenged.

There are various ways to challenge a will, one being that the person making the will (the testator) lacked the capacity to make the will.

To make a valid will, the testator must have some level of mental capacity at the time of writing or providing instructions for a will to be drafted.  This does not mean that they need to be mentally capable in all aspects of life, but that they have the relevant capacity to make a will.

In order to have the relevant capacity to make a will, the testator must be capable of understanding:

  • The nature and effect of making a will;
  • The extent of his or her estate;
  • The claims of those who might expect to benefit from the will; and
  • The testator should not have a mental illness that influences him or her to make bequests that he/she would not otherwise have made.

It is normal practice, when a solicitor is taking instructions to draft a will, for them to assess the testator’s capacity, and if they have any doubts, they should request the advice of a doctor to assess capacity.

However, sometimes doctors are unwilling to state whether a testator has the relevant capacity, and solicitors must make a judgment call.  Furthermore, where there is no solicitor involved, it is possible the testator did not have capacity.

In these scenarios, a will can be challenged for lack of testamentary capacity.  If a Court finds that the testator lacked capacity, the will can be held to be invalid.

Lack of capacity does not just mean that the deceased has a mental disorder which affects their decision-making capacity, it can also include, for example, substance abuse or grief causing lack of mental capacity.

If you are concerned about the mental capacity of the deceased when they made a will, you should contact a solicitor.

The best evidence in cases where there is a suspected lack of capacity are medical records and to investigate any potential claim for lack of mental capacity a solicitor should  obtain these and review them for signs that the deceased lacked the relevant mental capacity to make a will.

If there are signs that the deceased lacked capacity, your solicitor may well advise you to make a claim against the estate.  If a will is found to be invalid, then the estate may be distributed in accordance with previous wills or alternatively in line with the Intestacy Rules.

If you have concerns regarding the mental capacity of a relative when making a will, please  contact our contentious probate experts Zoe Davis:, Sheila Valand: or Jack Khurana: