There are many facets to challenging a will on each ground, however here we provide a basic summary.
Section 9 of the Wills Act 1837 clearly states that:
Simply put, if any of the above steps are not adhered to, the will can be challenged.
A will can be challenged if there is doubt on whether the testator had what is called “testamentary capacity”, i.e. had the ability to understand what they were doing at the time they made their will. The grounds for challenging a will for lack of testamentary capacity are outlined in the case of Banks v Goodfellow, which gives four limbs that would prove testamentary capacity – to succeed in a challenge, only one limb must fail.
To show testamentary capacity, the testator must have had (at the time of executing their will):
A person challenging a will on this ground would essentially be arguing that the testator did not in fact understand what they were signing, as opposed to not having the ability to understand, which would be a challenge on testamentary capacity as above. This would be, for example, if the testator had not read the will, or had fundamentally misunderstood what they were signing or what the provisions of the will would do.
This ground has a particularly high bar to meet, as a person challenging on this ground must show that the testator was so influenced by someone else that they had no choice but to execute the will in the way that they did. Importantly, evidence of pressure or persuasion is not enough to prove undue influence.
This ground, similar to undue influence, involves another person affecting the testator’s behaviour, however in this case it would be influencing them against someone else i.e. telling the testator things about another potential beneficiary that were not true, and because of this that person is not included in the will. As a very basic example, let’s say a mother has a son and a daughter, and the son consistently tells his mother that his sister is stealing from her. As such, the mother leaves everything to her son in her will.
Finally, there is of course a challenge to a will where it is believed that the will itself is fraudulent, i.e. that the testator did not in fact signed the will or that the document has been tampered with.
As demonstrated here, disputes over the validity of a will can be complex both legally and factually, and they generally involve a significant amount of evidence. As such, these disputes can be expensive and can often take a lot of time to resolve.