my father signed what he understood as a power of attorney for my grandmother (who was mentally ill) to take care of her affairs and get her the mental help she needed. however after my father signed the lawyer added more information to the document which made it seem that my grandmother signed over her house and land for 75.00. After review everything a few years after her death we(the family) found out this information and we need some direction on the what the law states.
In general, a mentally ill or incompetent person cannot legally sign a binding document. However, the presumption is that a person of majority age is competent, unless an action has been instigated to declare someone incompetent. Presumptions can sometimes be overcome. You should consult an attorney in your jurisdiction.
(This is intended as general information only and not intended to be legal advice. This attorney is not licensed to practice outside of North Carolina. Your specific situation may be different).