Fiduciaries can have both civil and criminal liability. Undue influence might be valid grounds for attacking a gift or a will. Undue influence is sometimes called overreaching. It usually means that there was overt persuasion, duress, force or coercion, or fraudulent misrepresentation made which created a lack of willpower. If a person was under undue influence when executing a will or a trust, the beneficiary might not be able to inherit.
Lack of capacity refers to lack of mental ability.
A person needs a certain amount of mental ability to create a valid will or a valid trust. Also that the person making the will has a general understanding of how the will or trust will operate on his property and beneficiaries. Often a relative or caretaker of the abused person concerned only with the older person's money, not their health or comfort. May have drug or alcohol abuse problems. Often appears angry at the older person.