Mental capacity is a legal test which is used to determine whether a person can make informed decisions for themselves. This determines whether somebody can or should have the ability to act on their own behalf and in this context manage their own estate in the form of writing a will. This is known as testamentary capacity, and it is essential in determining whether an individual can write their own will or if they already have a will, whether this is valid. The purpose of this is to protect an individual from making decisions which they are judged to not have the right capabilities to make.
How is mental capacity measured?

Testamentary capacity is determined through using the test formed in the case of Banks v Goodfellow.

  • This holds that the testator (person writing the will), must have the ability to do the following:
  • Be able to appreciate the nature and consequences of making a will
  • They must understand the extent of their property
  • Should consider any moral claims to their estate
  • Must not be affected by any disorder of the mind or insane delusion.

Therefore, a person is said to have mental capacity if they can weigh up their options to make an informed decision. The Mental Capacity Act goes one step further by requiring that the testator must be able to understand all the information which is relevant to the decision which includes any reasonably foreseeable consequences.

When dealing with certain clients lawyers also have an obligation to follow the ‘Golden rule’ as set out in the case of Kenward v Adams. This holds that when witnessing the wills of elderly or recently ill clients they have a responsibility to confirm their mental capacity with a medical practitioner beforehand.

The legal cases, the Mental Capacity act and the ‘Golden rule’ all work together to prevent those who lack mental capacity from making decisions which they are judged to be unable to sufficiently do.

How does this affect estate management?

If a person is judged to have mental capacity this means that their will is valid or if they do not have a will, they can write one and it will be valid. However, if someone fails the above criteria this will invalid their current will or if they have not written one, they will need someone else to do this on their behalf. Testamentary incapacity holds that the person writing the will lacked the mental and legal capabilities to do this at the time it was signed.

If someone is judged to lack testamentary capacity, there is a procedure in place which allows someone to write a will on their behalf. This process requires an application to the Court of Protection, which if granted an individual can have a statutory will made on their behalf.

If someone has died and has left a will, their family can contest it (argue it to be invalid, usually in court) if they believe their relative lacked mental capacity when they drafted it.This can be an extremely difficult decision to make as it means an individual’s wishes could be disregarded if they are held to have lacked capacity. However, this is the right thing to do if the individual was not mentally able to construct this will and consider the consequences of it. Legally, all people over 18 are presumed to have testamentary capacity so if an individual wishes to challenge a will they will have to submit sufficient evidence to the court so they can consider the testators capacity. If the person who has written the will has already passed away it will be the responsibility of the executor to provide evidence that the testator did in fact possess this capability.

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