Mistake, Undue Influence, Or Duress
If by MISTAKE OF FACT the plaintiff conveys title to the wrong person, or the wrong property is conveyed to the intended person, or the plaintiff is otherwise induced to act by reason of mistake, the transfer can be set aside. An alternative is to obtain a decree which reforms the instrument of conveyance so that it expresses the intent of the parties. In these cases, the conveyance is not void (without legal effect). The plaintiff actually intends a transfer, but the circumstances which cause the plaintiff's mind to operate are such that the court considers it unfair for the transferee to retain the property.
The same doctrine applies where the plaintiff is induced to make the conveyance through the exertion of UNDUE INFLUENCE (conduct by a person that dominates and destroys the free will of another). If the conduct of the defendant goes beyond persuading the plaintiff to convey—if it encompasses violence, threats of violence or restraint, or other injury—there is an even stronger case for charging the transferee as a constructive trustee on the ground of duress.
Law Library - American Law and Legal InformationFree Legal Encyclopedia: Constituency to CosignerConstructive Trust - Mistake, Undue Influence, Or Duress, Fraudulent Misrepresentation Or Concealment, Property Obtained By Homicide