Here in Florida, undue influence is the leading legal claim for invalidating wills. Prior to 2002, the claim of undue influence left the claimant with the burden of proof, requiring them to show that the will in question was created or modified by undue influence.
Many wills are created or modified in private, making proof that the deceased was unduly influenced hard to obtain. However, in 2002 a statute was enacted that took the burden of proof away from the claimant and gave it to the proponent, making it their responsibility to show that the will was not created or modified by undue influence.
It has been historically difficult to prove undue influence between spouses, yet many wills are contested for this reason. It is common for an individual to leave their estate or a portion of it to their spouse. In mixed families where children are removed from a parent's will and assets are solely awarded to a step-parent, there is often a question of if the changes were made through undue influence.
In these cases, proving the spouse was the influencer is rather difficult when the deceased was of sound mind during the modification. However, if there are other issues like cognitive impairment or declining health, family members may be able to better prove that the spouse was the influencer. In cases where an individual suffers from declining mental health, undue influence may exist when a spouse allows the impaired individual to make changes to their will when they know their spouse is not of sound mind.
Proving undue influence is difficult but not impossible. With the help of a skilled probate litigation attorney, showing cause that invalidates a will can be done. If you are concerned that a loved one's wishes were unduly influenced consider speaking to an attorney.