You can contest a Will in two different ways. You can contest the Will’s validity or alternatively, some category of claimants can make a claim against the estate under the Inheritance (Provision for Family and Dependants) Act 1975 if they have not had reasonable provision made for them.
When contesting a Will’s validity, you can make the claim based on several different factors.
Testamentary capacity: If the testator (the person that made the will) did not have good mental capacity at the time they made the Will, then this could render it invalid.
Undue influence: Where a testator was pressured into making a specific Will, the gift from this Will can be taken away from the person that pressured the testator.
This is more likely to be successful where the individual is suffering from a lack of sufficient mental capacity or significant health problems which may impact their judgment. To be successful in this type of claim, it needs to be demonstrated that someone has forced or pressured the testator to make the Will they made, as persuasion alone is legal.
Want of approval and knowledge: This is questioning whether the testator and fully understood and accepted the Will and its details when signing it. For example if the testator was deaf or blind when signing it this would be unlawful.
Lack of due execution: Making a claim on the grounds of lack of due execution means questioning if the Will was signed and witnessed properly. If it was not done properly this will render it invalid.
Forgery: It can be claimed that the signature on the Will that was made by the testator was actually forged by someone else making the Will invalid.
Fraudulent calumny: Here the testator could have been talked into excluding someone from the will under false pretences which renders the Will invalid.